Getting ANR in concurrent DB access - Java for Android App Development

I have used content provider in my project and override the applyBatch() for writting data into the database :
@override
public ContentProviderResult[] applyBatch(ArrayList<ContentProviderOperation> operations)
throws OperationApplicationException {
final Context context = getContext();
final SQLiteDatabase db = getDatabase(context);
db.beginTransaction();
try {
final int numOperations = operations.size();
final ContentProviderResult[] results = new ContentProviderResult[numOperations];
for (int i = 0; i < numOperations; i++) {
results = operations.get(i).apply(this, results, i);
}
db.setTransactionSuccessful();
return results;
} finally {
db.endTransaction();
}
}
If there is any writing operation to the database, applyBatch() method get called and in same time if I will make query from database(using CursorLoader), or call apply batch from different activity ANR comes and the following exception will also comes :
W/SQLiteConnectionPool(18025): The connection pool for database '+data+data+com.abc.xyz+databases+XYZ' has been unable to grant a connection to thread 8073 (pool-17-thread-3) with flags 0x2 for 64.105 seconds.
W/SQLiteConnectionPool(18025): Connections: 0 active, 1 idle, 0 available.
The above issue will not come if I remove the methode db.beginTrasaction() and db.endTrasaction() from applyBatch(). But in that case reading/writing time becomes large. I have used methods db.beginTrasaction() and db.endTrasaction() which reduces database access time to ten times.
Is there any approach, so that SQLite DataBse response quickly and there is no ANR ?

Related

Sending and Receiving MMS in Android

How to Send and Receive MMS in Android:
This is a guide I am creating to help all of you out there making messaging apps like sliding messaging, hopefully it will help someone at least get started in the right direction! This guide will not be a guide on how to read MMS messages, which is actually very simple. Here is a tutorial on that which will get you started: How to read MMS data in Android (The first answer is a lifesaver, it will get you where you need to go). Now onto sending and receiving!
First off, I want to say that all of this may seem very daunting, especially to a first time, independent Android app developer like I was when this started out, trying to manange time between this and college studies! A messaging app can be extremely difficult to write since there is no supported API to it at all and you have to go through lines and lines trying to decipher stock source code. Stick to it and you can definitely get there eventually I do feel that Google should add this type of thing into their API and document it though, so as to make it easier for us 3rd party developers without a giant team behind us! Come on Google!
Here's the steps in the order that I went through:
1) You need to import a lot of internal android classes, which can all be found here: GrepCode
Here are all of the files you will need to grab (there may be more, but I was able to in the end modify all of these files so that they don't depend on others such as taking out unnecessary lines of code, etc)
Code:
android.annotation.SdkConstant.java
android.database.sqlite.SqliteWrapper.java
android.net.ConnectivityManager.java
android.net.DhcpInfoInternal.java
android.net.IConnectivityManager.java
android.net.INetworkPolicyListener.java
android.net.InetworkPolicyManager.java
android.net.LinkAddress.java
android.net.LinkCapabilities.java
android.net.LinkProperties.java
android.net.NetworkIdentity.java
android.net.NetworkPolicy.java
android.net.NetworkPolicyManager.java
android.net.NetowkrQuotaInfo.java
android.net.NetowrkState.java
android.net.NetworkTemplate.java
android.net.NetworkUtils.java
android.net.ProxyProperties.java
android.net.RouteInfo.java
android.provider.Downloads.java
android.provider.Telephony.java
com.android.internal.annotations.VisibleForTesting.java
com.android.internal.net.LegacyVpnInfo.java
com.android.internal.net.VpnConfig.java
com.android.internal.net.VpnProfile.java
com.android.internal.telephony.EncodeException.java
com.android.internal.telephony.GsmAlphabet.java
com.android.internal.telephony.IccUtils.java
com.android.internal.telephony.SmsConstants.java
com.android.internal.telephony.TelephonyProperties.java
com.android.internal.util.ArrayUtils.java
com.android.internal.util.Objects.java
com.android.internal.util.Preconditions.java
com.android.mms.MmsConfig.java
com.android.mms.transaction.AbstractRetryScheme.java
com.android.mms.transaction.DefaultRetryScheme.java
com.android.mms.transaction.HttpUtils.java
com.android.mms.transaction.MmsSystemEventReceiver.java
com.android.mms.transaction.NotificationTransaction.java
com.android.mms.transaction.Observable.java
com.android.mms.transaction.Observer.java
com.android.mms.transaction.ProgressCalbackEntity.java
com.android.mms.transaction.PushReceiver.java
com.android.mms.transaction.ReadRecTransaction.java
com.android.mms.transaction.RetrieveTransaction.java
com.android.mms.transaction.RetryScheduler.java
com.android.mms.transaction.SendTransaction.java
com.android.mms.transaction.Transaction.java
com.android.mms.transaction.TransactionBundle.java
com.android.mms.transaction.TransactionService.java
com.android.mms.transaction.TransactionSettings.java
com.android.mms.transaction.TransactionState.java
com.android.mms.util.DownloadManager.java
com.android.mms.util.RateController.java
com.android.mms.util.SendingprogressTokenManager.java
com.google.android.collect.Sets.java
com.google.android.mms.ContentType.java
com.google.android.mms.InvalidHeaderValueException.java
com.google.android.mms.MmsException.java
com.google.android.mms.pdu.AcknowledgeInd.java
com.google.android.mms.pdu.Base64.java
com.google.android.mms.pdu.CharacterSets.java
com.google.android.mms.pdu.DeliveryInd.java
com.google.android.mms.pdu.EncodedStringValue.java
com.google.android.mms.pdu.GenericPdu.java
com.google.android.mms.pdu.MultimediaMessagePdu.java
com.google.android.mms.pdu.NotifictionInd.java
com.google.android.mms.pdu.NotifyRespInd.java
com.google.android.mms.pdu.PduBody.java
com.google.android.mms.pdu.PduComposer.java
com.google.android.mms.pdu.PduContentTypes.java
com.google.android.mms.pdu.PduHeaders.java
com.google.android.mms.pdu.PduParser.java
com.google.android.mms.pdu.PduPart.java
com.google.android.mms.pdu.PduPersister.java
com.google.android.mms.pdu.QuotedPrintable.java
com.google.android.mms.pdu.ReadOrigInd.java
com.google.android.mms.pdu.RetrieveConfjava
com.google.android.mms.pdu.SendConf.java
com.google.android.mms.pdu.SendRequ.java
com.google.android.mms.util.AbstractCache.java
com.google.android.mms.util.DownloadDrmHelper.java
com.google.android.mms.util.DrmConvertSession.jav
com.google.android.mms.util.PduCache.java
com.google.android.mms.util.PduCacheEntry.java
com.google.android.mms.util.SqliteWrapper.java
Whew, that was a ton of typing, hopefully its worth it! Haha. May be some typos in there too, but I'm sure you will be able to find the right one.
I know that's a lot, but I found it to be the easiest way of doing things. I'm not actually sure that all of these are required, and I may have missed a couple or added a couple extras, but you get the picture at least and thats most of them. You'll probably only end up using about 10% of those files, but since they all have others imported, I chose to import them all instead of the possibility of messing something up that was necessary. Like I said, its a lot, but almost all of them are really small so they won't increase the size of your app by more then half a megabyte at max (not sure on an exact number) so that's not really something to worry about. If you can make it by this daunting task, you should be good to go for the rest of the tutorial.
2) You need an MMS Part class that will be used to store MMS data you are going to be sending. Here is what mine looks like:
Code:
public class MMSPart {
public String Name = "";
public String MimeType = "";
public byte[] Data;
}
Just copy and paste this class.
Very straightforward as to what this will do for you, it is the actual file that we will be sending through out http connection. MimeType is the type of object that the part is, for example image/png or text/plain are the 2 that I use.
3) Next up, we need a class that will assist us in finding the system APNs. Here is mine:
Code:
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.provider.Telephony;
import android.text.TextUtils;
import android.widget.Toast;
public class APNHelper {
public APNHelper(final Context context) {
this.context = context;
}
@SuppressWarnings("unchecked")
public List<APN> getMMSApns() {
final Cursor apnCursor = this.context.getContentResolver().query(Uri.withAppendedPath(Telephony.Carriers.CONTENT_URI, "current"), null, null, null, null);
if ( apnCursor == null ) {
return Collections.EMPTY_LIST;
} else {
final List<APN> results = new ArrayList<APN>();
if ( apnCursor.moveToFirst() ) {
do {
final String type = apnCursor.getString(apnCursor.getColumnIndex(Telephony.Carriers.TYPE));
if ( !TextUtils.isEmpty(type) && ( type.equalsIgnoreCase("*") || type.equalsIgnoreCase("mms") ) ) {
final String mmsc = apnCursor.getString(apnCursor.getColumnIndex(Telephony.Carriers.MMSC));
final String mmsProxy = apnCursor.getString(apnCursor.getColumnIndex(Telephony.Carriers.MMSPROXY));
final String port = apnCursor.getString(apnCursor.getColumnIndex(Telephony.Carriers.MMSPORT));
final APN apn = new APN();
apn.MMSCenterUrl = mmsc;
apn.MMSProxy = mmsProxy;
apn.MMSPort = port;
results.add(apn);
Toast.makeText(context, mmsc + " " + mmsProxy + " " + port, Toast.LENGTH_LONG).show();
}
} while ( apnCursor.moveToNext() );
}
apnCursor.close();
return results;
}
}
private Context context;
}
Also, you will need an APN class, here is what that one looks like:
Code:
public class APN {
public String MMSCenterUrl = "";
public String MMSPort = "";
public String MMSProxy = "";
public APN(String MMSCenterUrl, String MMSPort, String MMSProxy)
{
this.MMSCenterUrl = MMSCenterUrl;
this.MMSPort = MMSPort;
this.MMSProxy = MMSProxy;
}
public APN()
{
}
}
Just copy and paste these classes.
The problem with this is that in Android 4.0 and up, Google blocks 3rd party access to APNs (though from trial and error I believe that you can access them on some touchwiz roms/phones, but not all). To get around this, in Sliding Messaging I had to have users input this information manually, so if you have users who will be on an API higher than 14 (ICS), you will need to have this option or it WILL ABSOLUTELY NOT work. At all. A little further down I'll show you how to implement so that you can try and find APNs, and if it fails then you can set them manually.
4) You need to include these permissions in the app for things to work and not get FCs because of lack of permissions:
Code:
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.RECEIVE_MMS" />
<uses-permission android:name="android.permission.READ_SMS"/>
<uses-permission android:name="android.permission.WRITE_SMS"/>
<uses-permission android:name="android.permission.WRITE_APN_SETTINGS" />
Just put them in the AndroidManifest with the rest. If you can't figure this step out maybe its time to start with something a little easier
As for the last one, write apn settings, I know for a fact you will not be able to compile your app through eclipse if you include it and you are working with Android 4.0+. It can only be applied to system apps only for API 14 and up and I don't know if you can include it without error if you are only targeting Gingerbread or not. More then likely you will have to take it out if you are not compiling your app as a system app by building it with the rest of the android source.
Please Note: I'm not actually sure that the internet permission is necessary, but the stock google app has it so I decided to include it.
5) Ok, now we have all of our classes we will use and it is time to send an MMS message. I will just copy the 2 functions that I use to do this directly below, and then explain them after that. Here they are:
Code:
public void sendMMS(final String recipient, final MMSPart[] parts)
{
ConnectivityManager mConnMgr = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
final int result = mConnMgr.startUsingNetworkFeature(ConnectivityManager.TYPE_MOBILE, "enableMMS");
if (result != 0)
{
IntentFilter filter = new IntentFilter();
filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (!action.equals(ConnectivityManager.CONNECTIVITY_ACTION))
{
return;
}
@SuppressWarnings("deprecation")
NetworkInfo mNetworkInfo = (NetworkInfo) intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if ((mNetworkInfo == null) || (mNetworkInfo.getType() != ConnectivityManager.TYPE_MOBILE_MMS))
{
return;
}
if (!mNetworkInfo.isConnected())
{
return;
} else
{
sendData(recipient, parts);
unregisterReceiver(this);
}
}
};
registerReceiver(receiver, filter);
} else
{
sendData(recipient, parts);
}
}
This function is fairly simple. All it does is tell the sytem that we are going to start using a mobile connection and it should connect using the term "enableMMS" so that we start the right type of connection. The variable result is set to the type of connection already active when we call this, and we are looking for it to be set to 0, meaning that our apns are already active. If this is the case, you can just skip right ahead to sending the MMS message. More than likely though, apns will not be active when you start the call, so you need to listen for a change in the connectivity through a broadcast receiver. That is what is going on inside the block of code where (result != 0). Once the receiver gets the correct type of connection, it calls the below function of sendData and unregisters itself so we don't leak receivers.
When the message is ready to be sent:
Code:
public void sendData(final String recipient, final MMSPart[] parts)
{
final Context context = this;
new Thread(new Runnable() {
@Override
public void run() {
final SendReq sendRequest = new SendReq();
final EncodedStringValue[] phoneNumber = EncodedStringValue.extract(recipient);
if (phoneNumber != null && phoneNumber.length > 0)
{
sendRequest.addTo(phoneNumber);
}
final PduBody pduBody = new PduBody();
if (parts != null)
{
for (MMSPart part : parts)
{
if (part != null)
{
try
{
final PduPart partPdu = new PduPart();
partPdu.setName(part.Name.getBytes());
partPdu.setContentType(part.MimeType.getBytes());
partPdu.setData(part.Data);
pduBody.addPart(partPdu);
} catch (Exception e)
{
}
}
}
}
sendRequest.setBody(pduBody);
final PduComposer composer = new PduComposer(context, sendRequest);
final byte[] bytesToSend = composer.make();
List<APN> apns = new ArrayList<APN>();
try
{
APNHelper helper = new APNHelper(context);
apns = helper.getMMSApns();
} catch (Exception e)
{
APN apn = new APN(sharedPrefs.getString("mmsc_url", ""), sharedPrefs.getString("mms_port", ""), sharedPrefs.getString("mms_proxy", ""));
apns.add(apn);
}
try {
HttpUtils.httpConnection(context, 4444L, apns.get(0).MMSCenterUrl, bytesToSend, HttpUtils.HTTP_POST_METHOD, !TextUtils.isEmpty(apns.get(0).MMSProxy), apns.get(0).MMSProxy, Integer.parseInt(apns.get(0).MMSPort));
ConnectivityManager mConnMgr = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
mConnMgr.startUsingNetworkFeature(ConnectivityManager.TYPE_MOBILE_MMS, "enableMMS");
IntentFilter filter = new IntentFilter();
filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
Cursor query = context.getContentResolver().query(Uri.parse("content://mms"), new String[] {"_id"}, null, null, "date desc");
query.moveToFirst();
String id = query.getString(query.getColumnIndex("_id"));
query.close();
ContentValues values = new ContentValues();
values.put("msg_box", 2);
String where = "_id" + " = '" + id + "'";
context.getContentResolver().update(Uri.parse("content://mms"), values, where, null);
context.unregisterReceiver(this);
}
};
registerReceiver(receiver, filter);
} catch (Exception e) {
Cursor query = context.getContentResolver().query(Uri.parse("content://mms"), new String[] {"_id"}, null, null, "date desc");
query.moveToFirst();
String id = query.getString(query.getColumnIndex("_id"));
query.close();
ContentValues values = new ContentValues();
values.put("msg_box", 5);
String where = "_id" + " = '" + id + "'";
context.getContentResolver().update(Uri.parse("content://mms"), values, where, null);
((Activity) context).getWindow().getDecorView().findViewById(android.R.id.content).post(new Runnable() {
@Override
public void run() {
Toast.makeText(context, "MMS Error", Toast.LENGTH_SHORT).show();
}
});
}
}
}).start();
}
This function is where all the magic happens. First, we need to create a new thread to run on because you can't access an HTTP connection on the UI thread (I ran into this error the first time around since I had never worked with data connections before). Once that thread is running, we create a new SendReq object which is what we will be sending through the http request. You will need to encode your recipient (this part of the code can also be used to support group messaging, but I have not included that code, you will need to write it yourself if you so choose. You can attach multiple addresses by calling sendRequest.addTo() multiple times) and attach it to the sendRequest. Next up, attach your MMSPart file using a for loop. Here is how to initialize that MMSPart to whatever you want to include in it:
Code:
Bitmap b = ________; // Whatever your bitmap is that you want to send
ByteArrayOutputStream stream = new ByteArrayOutputStream();
b.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
MMSPart[] parts = new MMSPart[1];
parts[0] = new MMSPart();
parts[0].Name = "Image";
parts[0].MimeType = "image/png";
parts[0].Data = byteArray;
Using this, you can also add text to the request with the mimetype "text/plain" and encode text as a byte array so that it can be attached in the same mannor. I won't post that code, you should be able to figure it out.
Back to the original sendData function, we can now attach the pduBody which includes all of the byte arrays that we want to send, in this specific case, just an image and no text. After that, all that is left is to actually create the byte array to send, bytesToSend, which can be done very easily through internal classes.
Now we are ready to make the actual send request, which must be done through the users APNs using an http_post method. But first, we need to retrieve APNs. As I said earlier, if a user is running an Android version less then 4.0, then the app should be able to get the system defined APNs through the APN helper class that I provided (still no promises on this though as it has been untested, I don't have an old phone anymore to test on). Surround the request to APNHelper with a try/catch block so that we can catch the error of insigificant permissions, and then apply your user defined custom APNs that will actually work. I have users enter these in settings, thats why you see them being set through sharedPreference strings. you can manually type in whatever strings you want to for your network during testing phases though and that should work fine, just remember different networks use different APNs.
Ahh finally we are ready to make our Http request. This is fairly simple, as it is just one line of code which you should be able to directly take from my example if you initialize apns the same way I have:
Code:
HttpUtils.httpConnection(context, 4444L, apns.get(0).MMSCenterUrl, bytesToSend, HttpUtils.HTTP_POST_METHOD, !TextUtils.isEmpty(apns.get(0).MMSProxy), apns.get(0).MMSProxy, Integer.parseInt(apns.get(0).MMSPort));
You can look at javadocs for this function if you want to know what all of this is, but just know that it will make a post request through your MMSC you have defined and then send the message through the proxy and port (if those are needed, some carriers do not require them). Also, remember to add a catch block around this in case the sending fails for whatever reason, and tell your users that the request has failed. In this example, when the message fails to send, it moves the message to msg_box = 5, which is where MMS with errors are stored. This is simply updating the database with a new location for our recently failed message.
Last thing we have to do is listen for when the message has sent. This is where I've completely made up a function, and it functions correctly for ALMOST everyone (the only people not so far are Sprint users, and I haven't found a way around it yet). To do this, after our request, we register a new connectivity receiver just as we did when we were preparing to send a message, and this time around, when the state of the phones internet connection changes - usually dropping out of the APN request space I believe - we can move the message from the outbox to the sent message box and boom, message sent.
Yay, you should have just been able to send your first MMS message! (Unless I forgot a step in there lol) That's exciting stuff! Notice now though, that although you sent the message (and you have coded in how to change which message box the message is in), the message didn't get saved to the database so you can't actually see it in the app. That doesn't do most of us any good, so next step is how to save it to the SMS database on your phone.
6) Here we save the message, I'll just list out the functions again and then explain them after that:
Code:
public static Uri insert(Context context, String[] to, String subject, byte[] imageBytes)
{
try
{
Uri destUri = Uri.parse("content://mms");
// Get thread id
Set<String> recipients = new HashSet<String>();
recipients.addAll(Arrays.asList(to));
long thread_id = Telephony.Threads.getOrCreateThreadId(context, recipients);
// Create a dummy sms
ContentValues dummyValues = new ContentValues();
dummyValues.put("thread_id", thread_id);
dummyValues.put("body", "Dummy SMS body.");
Uri dummySms = context.getContentResolver().insert(Uri.parse("content://sms/sent"), dummyValues);
// Create a new message entry
long now = System.currentTimeMillis();
ContentValues mmsValues = new ContentValues();
mmsValues.put("thread_id", thread_id);
mmsValues.put("date", now/1000L);
mmsValues.put("msg_box", 4);
//mmsValues.put("m_id", System.currentTimeMillis());
mmsValues.put("read", 1);
mmsValues.put("sub", subject);
mmsValues.put("sub_cs", 106);
mmsValues.put("ct_t", "application/vnd.wap.multipart.related");
if (imageBytes != null)
{
mmsValues.put("exp", imageBytes.length);
} else
{
mmsValues.put("exp", 0);
}
mmsValues.put("m_cls", "personal");
mmsValues.put("m_type", 128); // 132 (RETRIEVE CONF) 130 (NOTIF IND) 128 (SEND REQ)
mmsValues.put("v", 19);
mmsValues.put("pri", 129);
mmsValues.put("tr_id", "T"+ Long.toHexString(now));
mmsValues.put("resp_st", 128);
// Insert message
Uri res = context.getContentResolver().insert(destUri, mmsValues);
String messageId = res.getLastPathSegment().trim();
// Create part
if (imageBytes != null)
{
createPartImage(context, messageId, imageBytes);
}
// Create addresses
for (String addr : to)
{
createAddr(context, messageId, addr);
}
//res = Uri.parse(destUri + "/" + messageId);
// Delete dummy sms
context.getContentResolver().delete(dummySms, null, null);
return res;
}
catch (Exception e)
{
e.printStackTrace();
}
return null;
}
Code:
private static Uri createPartImage(Context context, String id, byte[] imageBytes) throws Exception
{
ContentValues mmsPartValue = new ContentValues();
mmsPartValue.put("mid", id);
mmsPartValue.put("ct", "image/png");
mmsPartValue.put("cid", "<" + System.currentTimeMillis() + ">");
Uri partUri = Uri.parse("content://mms/" + id + "/part");
Uri res = context.getContentResolver().insert(partUri, mmsPartValue);
// Add data to part
OutputStream os = context.getContentResolver().openOutputStream(res);
ByteArrayInputStream is = new ByteArrayInputStream(imageBytes);
byte[] buffer = new byte[256];
for (int len=0; (len=is.read(buffer)) != -1;)
{
os.write(buffer, 0, len);
}
os.close();
is.close();
return res;
}
Code:
private static Uri createAddr(Context context, String id, String addr) throws Exception
{
ContentValues addrValues = new ContentValues();
addrValues.put("address", addr);
addrValues.put("charset", "106");
addrValues.put("type", 151); // TO
Uri addrUri = Uri.parse("content://mms/"+ id +"/addr");
Uri res = context.getContentResolver().insert(addrUri, addrValues);
return res;
}
I didn't write these functions, credit to Vodemki on Stack Overflow. All you have to do is call the insert function and it will do all of the work for you. Send that fuction the activity context, a string array of the numbers who you sent the message to, a subject for the message, and the same byte array of the image you passed earlier to your MMS part file. You can look at the code for inserting the image and reproduce this to do the same for a string of text you are sending with the image.
You will want to actually call these funtions right after you push the send button for example, to first save the message and then you can send it and update it later after it has sent or failed to send.
Ok, now that will successfully allow you to put the MMS message in the database. For some reason, these messages just show up as blank messages in the stock app, not sure why, but Sliding Messaging is able to read them at least, so depending on your implementation, yours should be able to do so as well.
Now all this function does is insert the image. I don't want to give away all of my secrets for Sliding Messaging so you will have to go through and find out how to insert text and group message addresses yourself, I think that's fair enough and if you've made it this far in your app, you shouldn't have to much of a problem with it
Wow, we just sent and saved that message to our phone, that means we are halfway home! (Nice rhyme huh )
Onto receiving in the next post.
7) First up, you'll have to know a little something about querying the mms-sms database, read up on that first if you haven't already (first link I have posted at the top). This is all out of my brain and what I was able to do from experience, and seems to work very well... you won't find a tutorial anywhere else on the internet of how to do this (at least I couldn't anywhere). I'm not going to just give you a simple function for this one though, you will have to adapt the code according to how you want it to be used. Once again, here is the code you will need to use:
Code:
id = ________; // this is the id of your MMS message that you are going to search for
Cursor locationQuery = context.getContentResolver().query(Uri.parse("content://mms/"), new String[] {"m_size", "exp", "ct_l", "_id"}, "_id=?", new String[]{id}, null);
locationQuery.moveToFirst();
String exp = "1";
String size = "1";
try
{
size = locationQuery.getString(locationQuery.getColumnIndex("m_size"));
exp = locationQuery.getString(locationQuery.getColumnIndex("exp"));
} catch (Exception f)
{
}
String location = locationQuery.getString(locationQuery.getColumnIndex("ct_l"));
The above function is where you query the message you are interested in downloading, and get data from it such as expiration date, size, and location on a server. The date will be a date in milliseconds that you can format accordingly and display to the screen if you so choose, and the size will be in bytes, but you will probably want to convert to kb by dividing by 1000. As for the location, that is what we are going to use to download the message:
Code:
List<APN> apns = new ArrayList<APN>();
try
{
APNHelper helper = new APNHelper(context);
apns = helper.getMMSApns();
} catch (Exception e)
{
APN apn = new APN(sharedPrefs.getString("mmsc_url", ""), sharedPrefs.getString("mms_port", ""), sharedPrefs.getString("mms_proxy", ""));
apns.add(apn);
}
Get your APNs the same way as we did before when sending, I won't explain this again.
Code:
try {
byte[] resp = HttpUtils.httpConnection(
context, SendingProgressTokenManager.NO_TOKEN,
downloadLocation, null, HttpUtils.HTTP_GET_METHOD,
!TextUtils.isEmpty(apns.get(0).MMSProxy),
apns.get(0).MMSProxy,
Integer.parseInt(apns.get(0).MMSPort));
RetrieveConf retrieveConf = (RetrieveConf) new PduParser(resp).parse();
PduPersister persister = PduPersister.getPduPersister(context);
Uri msgUri = persister.persist(retrieveConf, Inbox.CONTENT_URI, true,
true, null);
ContentValues values = new ContentValues(1);
values.put(Mms.DATE, System.currentTimeMillis() / 1000L);
SqliteWrapper.update(context, context.getContentResolver(),
msgUri, values, null, null);
SqliteWrapper.delete(context, context.getContentResolver(),
Uri.parse("content://mms/"), "thread_id=? and _id=?", new String[] {threadIds, msgId});
((Activity) context).getWindow().getDecorView().findViewById(android.R.id.content).post(new Runnable() {
@Override
public void run() {
Toast.makeText(context, "Message Received", Toast.LENGTH_SHORT).show();
}
});
} catch (Exception e) {
e.printStackTrace();
((Activity) context).getWindow().getDecorView().findViewById(android.R.id.content).post(new Runnable() {
@Override
public void run() {
Toast.makeText(context, "Download Failed", Toast.LENGTH_SHORT).show();
}
});
}
This request is much the same as the previous we used when sending the message, except this time we use a get request instead of post, send the funtion a null where before it was out bytesToSend array, and receive a byte array from it. Once you have received this byte array, you can easily use internal classes to save the message to the database (these messages are saved 100% correctly and will show up in the stock app once downloaded, unlike before) and then delete the old message stored there that only had location data for the message to be downloaded. I won't go into much more detail then that, it should be easy enough to understand just from the code.
I have this function tied to a button press, but in theory you should also be able to register a WAP_PUSH_RECEIVED broadcast receiver that saves the message automatically when your phone gets one (WAP is the type of broadcast you get when receiving MMS data). I'm not going to post anything here about that because I haven't done it, but if you want, all of the code is the same and you can easily base it happening off of a setting in your app and the network connectivity state when the message is received.
Another Note: There is probably a way to use the above code with persisters etc to be able to save an MMS to the database in a much easier way, but I haven't looked into that at all, mostly because the code I posted in step 6 works just fine and I don't see a need for much else if you can handle just copying and pasting those functions.
Now I think that may be it... we covered sending MMS, saving sent MMS and finally receiving MMS! Fun stuff!
In conclusion, I just want to give something back to the community that has given my app, Sliding Messaging, so much love over the past couple of months. I hope this helps someone out there, because as far as I know and could find, this is the only full MMS tutorial there is for Android (and the only one at all for actually downloading MMS from the internet) and should get everything done that you need! Ask any questions you want and feel free to PM me if you need more assistance.
Now no one out there should have any excuse for not including at least some MMS support in your messaging apps! Hopefully this will save you from days upon days of research to no avail on the subject and unjust criticism from people who know absolutely nothing about the topic like I did (Had one person tell me to f-off and if I couldn't get it working, then his $0.99 entitled him to say that I needed to hire someone else who was actually competent at programming and spend all of my college savings so that person would do it for me ... to that person I say, HAHA, I did it. lol) Your users will be happy people if you get this implemented!
Also guys, I wouldn't mind getting a little credit if anyone out there uses this tutorial to get things up and running, but its not necessary if you don't want! Instead you could just buy me a beer and donate to me To the people who actually read through these last 3 paragraphs, I say thank you! Hopefully this tutorial can at least get you started, wish I had it reference when I was adding the support in!
Sources:
1) How to Read MMS Data in Android
2) Android Add MMS to Database
3) MMS in Android: Part 1
4) GrepCode
5) My own experience
Cheers, and good luck to anyone trying this out this is my first tutorial so if you find anything missing or any typos, let me know!
grepcode files missing
I tried to download classes from your given link 'Grepcode'.
It is missing the contents of com.google folder even it do not contain folder named google in com folder. (i tried different versions like 4.2.1,4.2.2 etc .. still same problem )
can you give me any other link to download classes ?
Cool, thanks.
(You might want to add [Guide] to your thread title. For now it looks like a question. )
Thanks very much for doing this. Had to do a bit of searching on the internet for some of the files, and some of the functions needed slight modification but this was enough of a push in the right direction that I've got mms sending working. Great job and good luck with the continued success of your app!
Also- your responses on the android marketplace to people leaving stupid feedback make me laugh!
Getting Connection Refused error
Hi,
I tried your code. I am getting the APN settings perfectly. But a soon as the httpClient tries to connect to my MMSC it throws ConnectionRefused Error.
Please help me. Its been head-scratcher 3 days in a row now.
Thanks. in advance.
Please help
I am not able to import the classes with name
com.android.mms.*
and
com.google.*
I downloaded the android-4.2.2_r1.jar and also android-4.4_r1.jar
But these jars do not contain all required classes.
Please help how to add these classes.
Regarding the missing classes
Hi,
I am looking for a solution to programmatically sending MMS through my Android Application.
Some classess are missing(com.google.*) in the jar downloaded from grepcode.
Can anybody help in this regard?
Thanks.
Missing Function
hi
When I want to insert MMS message in DB, eclipse says "Telephony.Threads.getOrCreateThreadId" is undefined!
What should I do?
Thanks
CursorIndexOutOfBoundsException
hi ,
I get exception like this
android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0
AS per yourCode
Cursor query = context.getContentResolver().query(Uri.parse("content://mms"), new String[]
{
"_id"
}, null, null, "date desc");
query.moveToFirst();
String id = query.getString(query.getColumnIndex("_id"));
get force close when i try to get id
Does this still work? I noticed a lot of the comments say there are missing stuff. I need a good tutorial for implementing MMS sending/ receiving.

[DEV]Any one heard about BatteryStatusImpl class from private api

Any android gurus out there who have used this class previously ???
I instantiate the class using the following code:
Code:
IBatteryStats mIStats = IBatteryStats.Stub.asInterface(
ServiceManager.getService("batteryinfo"));
byte[] data = null;
try {
data = mIStats.getStatistics();
} catch (RemoteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Parcel parcel = Parcel.obtain();
parcel.unmarshall(data, 0, data.length);
parcel.setDataPosition(0);
BatteryStatsImpl mStats = BatteryStatsImpl.CREATOR.createFromParcel(parcel);
but BatteryStatsusImpl writesin the log:
File corrupt: battery history buffer too large (a big num)
and nothing happens the app just stops responding
and no Battery Data Available is displayed
through the debugger i got to know that the batteryinfo service returned data but still no result
I use the restricted apis as is in the AP14 android git without any modification
what do I do? please help i need to get per app battery usage.

[Q] Parse Bluetooth received string

Hi, I have a newbie question..
I have modified the bluetoothChat example to get serial data from my pc to my phone over bluetooth.
The code uses the following code to keep listening for incoming data:
Code:
public void run() {
Log.i(TAG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024];
int bytes = 0;
// byte x = 0;
// Keep listening to the InputStream while connected
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(BluetoothChat.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(TAG, "disconnected", e);
connectionLost();
// Start the service over to restart listening mode
BluetoothChatService.this.start();
break;
}
}
}
And in the MainActivity the following code when data is received:
Code:
case MESSAGE_READ:
byte [] readBuf;
//readBuf = (byte[]) msg.obj;
readBuf = (byte[]) msg.obj;
String readMessage = new String(readBuf, 0, msg.arg1); // create string from bytes array
messageString = messageString + readMessage;
if (messageString.length()<10){
TextView text = (TextView) findViewById(R.id.textView1); // Display output
text.setText("<10....");
break;
}
sb.append(readMessage); // append string
int endOfLineIndex = sb.indexOf("#"); // determine the end-of-line
if (endOfLineIndex > 0) { // if end-of-line,
String sbprint = sb.substring(0, endOfLineIndex); // extract string
sb.delete(0, sb.length()); // and clear
TextView text = (TextView) findViewById(R.id.textView1); // Display output
text.setText(sbprint);
mConversationArrayAdapter.add(mConnectedDeviceName+": " + readMessage);
}
break;
As shown i have added a endOfLineIndex loop to find the end of the received string and show the received string in a textfield. The problem with my code is when sending a string like "0123456789#" the shown text in the textView1 is mostly not the send string.. I get strings like 0123,4560123456789, etc.. Somehow there is still data in the buffer i quess.
Is there a way to clear or ignore the received data and only parse the wanted string form the buffer? If this is possible i can add a start identifier to the string..
The main goal is too parse a string like: #150,000,001,000,0.0,-0.1,40.3,144.0,001,OKE where each value is a variable which needed to be placed in a textview.
Thanks for any suggestions!
Kind regards,
Bas
This one "0123456789#" should return "0123456789". Does it?
You invoke substring().
Quote from the docs:
The substring begins at the specified beginIndex and extends to the character at index endIndex - 1.
Click to expand...
Click to collapse
(http://docs.oracle.com/javase/1.4.2/docs/api/java/lang/String.html#substring(int, int))
That means that the last character (the #) is missed out.
Thanks Nikwen,
I do miss out the end off string character #. The problem is i get different strings out of the buffer... If i send 0123456789# with a one second interval i get different results.. sometimes i get the string like expected which is 0123456789. but most of the time i get results like 0123, 456789,12,1,etc etc. it looks like the buffer is not cleared or something

Java is too complex for begginer lovers

I love Android. I want to learn to develop apps. I keep reading tutorials. I got dissapointed and read about HTML frameworks (phonegap, etc). I came back to Android Native Java. I want to learn from the roots. However, some things discourages me....
All this part of the code is just for making a request to the Openweather API and get the json data (plus a little debugging stuff); which in Python or similar languages you only have to care about
- importing the library that handles http requests
- make the request in one function and save it into a json object
Code:
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
// Will contain the raw JSON response as a string.
String forecastJsonStr = null;
String format = "json";
String units = "metric";
int numDays = 7;
try {
final String FORECAST_BASE_URL =
"<the-domain>/data/2.5/forecast/daily?";
final String QUERY_PARAM = "q";
final String FORMAT_PARAM = "mode";
final String UNITS_PARAM = "units";
final String DAYS_PARAM = "cnt";
Uri builtUri = Uri.parse(FORECAST_BASE_URL).buildUpon()
.appendQueryParameter(QUERY_PARAM, params[0])
.appendQueryParameter(FORMAT_PARAM, format)
.appendQueryParameter(UNITS_PARAM, units)
.appendQueryParameter(DAYS_PARAM, Integer.toString(numDays))
.build();
URL url = new URL(builtUri.toString());
Log.v(LOG_TAG, "Built URI " + builtUri.toString());
// Create the request to OpenWeatherMap, and open the connection
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
forecastJsonStr = buffer.toString();
Log.v(LOG_TAG, "Forecast string: " + forecastJsonStr);
} catch (IOException e) {
Log.e(LOG_TAG, "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
return null;
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
This is the complete Class:
Code:
public class FetchWeatherTask extends AsyncTask<String, Void, String[]> {
private final String LOG_TAG = FetchWeatherTask.class.getSimpleName();
/* The date/time conversion code is going to be moved outside the asynctask later,
* so for convenience we're breaking it out into its own method now.
*/
private String getReadableDateString(long time){
// Because the API returns a unix timestamp (measured in seconds),
// it must be converted to milliseconds in order to be converted to valid date.
Date date = new Date(time * 1000);
SimpleDateFormat format = new SimpleDateFormat("E, MMM d");
return format.format(date).toString();
}
/**
* Prepare the weather high/lows for presentation.
*/
private String formatHighLows(double high, double low) {
// For presentation, assume the user doesn't care about tenths of a degree.
long roundedHigh = Math.round(high);
long roundedLow = Math.round(low);
String highLowStr = roundedHigh + "/" + roundedLow;
return highLowStr;
}
/**
* Take the String representing the complete forecast in JSON Format and
* pull out the data we need to construct the Strings needed for the wireframes.
*
* Fortunately parsing is easy: constructor takes the JSON string and converts it
* into an Object hierarchy for us.
*/
private String[] getWeatherDataFromJson(String forecastJsonStr, int numDays)
throws JSONException {
// These are the names of the JSON objects that need to be extracted.
final String OWM_LIST = "list";
final String OWM_WEATHER = "weather";
final String OWM_TEMPERATURE = "temp";
final String OWM_MAX = "max";
final String OWM_MIN = "min";
final String OWM_DATETIME = "dt";
final String OWM_DESCRIPTION = "main";
JSONObject forecastJson = new JSONObject(forecastJsonStr);
JSONArray weatherArray = forecastJson.getJSONArray(OWM_LIST);
String[] resultStrs = new String[numDays];
for(int i = 0; i < weatherArray.length(); i++) {
// For now, using the format "Day, description, hi/low"
String day;
String description;
String highAndLow;
// Get the JSON object representing the day
JSONObject dayForecast = weatherArray.getJSONObject(i);
// The date/time is returned as a long. We need to convert that
// into something human-readable, since most people won't read "1400356800" as
// "this saturday".
long dateTime = dayForecast.getLong(OWM_DATETIME);
day = getReadableDateString(dateTime);
// description is in a child array called "weather", which is 1 element long.
JSONObject weatherObject = dayForecast.getJSONArray(OWM_WEATHER).getJSONObject(0);
description = weatherObject.getString(OWM_DESCRIPTION);
// Temperatures are in a child object called "temp". Try not to name variables
// "temp" when working with temperature. It confuses everybody.
JSONObject temperatureObject = dayForecast.getJSONObject(OWM_TEMPERATURE);
double high = temperatureObject.getDouble(OWM_MAX);
double low = temperatureObject.getDouble(OWM_MIN);
highAndLow = formatHighLows(high, low);
resultStrs[i] = day + " - " + description + " - " + highAndLow;
}
for (String s : resultStrs) {
Log.v(LOG_TAG, "Forecast entry: " + s);
}
return resultStrs;
}
@Override
protected String[] doInBackground(String... params) {
// If there's no zip code, there's nothing to look up. Verify size of params.
if (params.length == 0) {
return null;
}
// These two need to be declared outside the try/catch
// so that they can be closed in the finally block.
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
// Will contain the raw JSON response as a string.
String forecastJsonStr = null;
String format = "json";
String units = "metric";
int numDays = 7;
try {
// Construct the URL for the OpenWeatherMap query
// Possible parameters are avaiable at OWM's forecast API page
final String FORECAST_BASE_URL =
"<the-domain>/data/2.5/forecast/daily?";
final String QUERY_PARAM = "q";
final String FORMAT_PARAM = "mode";
final String UNITS_PARAM = "units";
final String DAYS_PARAM = "cnt";
Uri builtUri = Uri.parse(FORECAST_BASE_URL).buildUpon()
.appendQueryParameter(QUERY_PARAM, params[0])
.appendQueryParameter(FORMAT_PARAM, format)
.appendQueryParameter(UNITS_PARAM, units)
.appendQueryParameter(DAYS_PARAM, Integer.toString(numDays))
.build();
URL url = new URL(builtUri.toString());
Log.v(LOG_TAG, "Built URI " + builtUri.toString());
// Create the request to OpenWeatherMap, and open the connection
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
forecastJsonStr = buffer.toString();
Log.v(LOG_TAG, "Forecast string: " + forecastJsonStr);
} catch (IOException e) {
Log.e(LOG_TAG, "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
return null;
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
try {
return getWeatherDataFromJson(forecastJsonStr, numDays);
} catch (JSONException e) {
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
// This will only happen if there was an error getting or parsing the forecast.
return null;
}
}
I mean, I know this code can be reduced, but I'm angry about the way it works. Everything needs to be passed to another object! And even rembember all those castings! Castings everywhere!
- The builded URI to the URL.
- The URL to the HttpConection variable.
- Once you connect, save that into the InputStream.
- Make a StringBuffer because we are going to send line by line everything.
- Then create the reader = new BufferedReader(new InputStreamReader(inputStream)).
- Append the lines to the buffer and return if it's ok.
- Else catch all the errors and be sure to close all the connections.
Damn Java !
Forgive me. You'll hate me.
Java is readable, that's the truth... but don't tell me that it is easy for a normal person.
Am I the only one?
If you are a beginner and will straight move to these classes. You will obviously find Java difficult. But Java is very easy if you move step by step from start
Sent from my XT1033 using XDA Premium 4 mobile app
---------- Post added at 04:18 PM ---------- Previous post was at 04:16 PM ----------
And that library also does the same thing inside. Only difference is, your work is already done by author of the library.
Sent from my XT1033 using XDA Premium 4 mobile app
Java is definitely a very verbose language but it's also widely used and so you will find many libraries that do tasks like grab JSON data from a service that have already been implemented for you
manwoman said:
Damn Java !
Forgive me. You'll hate me.
Java is readable, that's the truth... but don't tell me that it is easy for a normal person.
Am I the only one?
Click to expand...
Click to collapse
I don't think you're the only one. It's easy to get scared away by the many too verbose examples available, the key is to look at what you're trying to achieve and then break it up into those parts.
Your code listing is (I think) an attempt to show all steps to get the forecast data, but if that would have been broken up into smaller steps I don't think you'd look at it as quite as bad.
You would then have methods like
Code:
URL getForecastUrl(String parameter);
Code:
BufferedReader getUrl(URL url) { }
Code:
String readAll(BufferedReader reader) {}
Each of which would have had something like 6-7 lines of simple, cohesive code.
I understand your point, but in this particular scenario I think you're the victim of a poorly structured code sample rather than a too verbose language.
If you think the default implementation is too complicated, here are also many java libraries which will make your life easier.

[Tutorial] Learn to save data with SQLite on Android

Hello,
I create that thread to present you a tutorial learning you to save data with SQLite on Android. This tutorial is also available in video on Youtube :
Learn to save data with SQLite on Android
On Android, there are several solutions to persist data between users’ sessions. One solution is to use a relational database to persist data and then to be able to query easily these data. In standard, Android SDK comes with a SQLite implementation. Biggest advantage of SQLite integration to Android OS is the fact that there is no need to to setup the database. So, no administration of this database. SQLite is embedded in standard and each application can have its SQLite database.
The only job that developers must make is to define SQL tables and statements for creating and updating data. Access to an SQLite database involves accessing the file system. So, it can be a slow operation. To avoid ANR (Application Not Responding) errors, it’s recommended to perform database operations asynchronously.
When an application creates and uses a SQLite database, it will be saved by default in the directory : DATA/data/APP_PACKAGE/databases/FILENAME .
1. Architecture
All classes needed to manage databases in Android SDK are contained in the package android.database . The package android.database.sqlite contains the SQLite specific classes.
SQLite API is centered around 2 main classes :
SQLiteOpenHelper that is an helper class to extend to manage database operations.
SQLiteDatabase that is the base class for working with a SQLite database in Android.
2. SQLiteOpenHelper
When you want to work with a SQLite database in Android, you must extend SQLiteOpenHelper class. In the constructor of your subclass you call the super() method of SQLiteOpenHelper, specifying the database name and the current database version.
You need also to override the following methods :
onCreate() that is called when database is accessed but not yet created.
onUpgrade() called when you choose to increment the version number of the database. In this method you can manage the migration process between two databases versions.
Both methods get and SQLiteDatabase instance in parameter which is the way to communicate with the database.
Furthermore, SQLiteOpenHelper provides 2 methods to get access to an SQLiteDatabase instance object respectively in read and in write modes :
getReadableDatabase() for read mode.
getWriteableDatabase() for write mode.
3. SQLiteDatabase
SQLiteDatabase is the class used to communicate with a SQLite database. It exposes several methods to interact with database like insert(), update() or delete().
In addition, it lets you to make queries via rawQuery() to queries made directly in SQL or via query() method. This last method provides a structured interface for specifying a SQL query.
4. Practice
Now, you know theory about SQLite in Android context. We can put in practice all the concepts. To achieve that, we’re going to make a database with a players table letting us to store NBA players.
To start, we create a simple Player Java POJO :
Code:
public class Player {
private int id;
private String name;
private String position;
private int height;
public Player() {
}
public Player(int id, String name, String position, int height) {
this.id = id;
this.name = name;
this.position = position;
this.height = height;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPosition() {
return position;
}
public void setPosition(String position) {
this.position = position;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
@Override
public String toString() {
return name + " - " + position + " - " + height + " cm";
}
}
Then, we must create the SQLiteOpenHelper extended class to manage our application database. Code is here :
Code:
package com.ssaurel.samples.sqlite;
import java.util.LinkedList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class SQLiteDatabaseHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "PlayersDB";
private static final String TABLE_NAME = "Players";
private static final String KEY_ID = "id";
private static final String KEY_NAME = "name";
private static final String KEY_POSITION = "position";
private static final String KEY_HEIGHT = "height";
private static final String[] COLUMNS = { KEY_ID, KEY_NAME, KEY_POSITION,
KEY_HEIGHT };
public SQLiteDatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
String CREATION_TABLE = "CREATE TABLE Players ( "
+ "id INTEGER PRIMARY KEY AUTOINCREMENT, " + "name TEXT, "
+ "position TEXT, " + "height INTEGER )";
db.execSQL(CREATION_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// you can implement here migration process
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
this.onCreate(db);
}
public void deleteOne(Player player) {
// Get reference to writable DB
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_NAME, "id = ?", new String[] { String.valueOf(player.getId()) });
db.close();
}
public Player getPlayer(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_NAME, // a. table
COLUMNS, // b. column names
" id = ?", // c. selections
new String[] { String.valueOf(id) }, // d. selections args
null, // e. group by
null, // f. having
null, // g. order by
null); // h. limit
if (cursor != null)
cursor.moveToFirst();
Player player = new Player();
player.setId(Integer.parseInt(cursor.getString(0)));
player.setName(cursor.getString(1));
player.setPosition(cursor.getString(2));
player.setHeight(Integer.parseInt(cursor.getString(3)));
return player;
}
public List<Player> allPlayers() {
List<Player> players = new LinkedList<Player>();
String query = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
Player player = null;
if (cursor.moveToFirst()) {
do {
player = new Player();
player.setId(Integer.parseInt(cursor.getString(0)));
player.setName(cursor.getString(1));
player.setPosition(cursor.getString(2));
player.setHeight(Integer.parseInt(cursor.getString(3)));
players.add(player);
} while (cursor.moveToNext());
}
return players;
}
public void addPlayer(Player player) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, player.getName());
values.put(KEY_POSITION, player.getPosition());
values.put(KEY_HEIGHT, player.getHeight());
// insert
db.insert(TABLE_NAME,null, values);
db.close();
}
public int updatePlayer(Player player) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, player.getName());
values.put(KEY_POSITION, player.getPosition());
values.put(KEY_HEIGHT, player.getHeight());
int i = db.update(TABLE_NAME, // table
values, // column/value
"id = ?", // selections
new String[] { String.valueOf(player.getId()) });
db.close();
return i;
}
}
Database is created in the constructor of the extended class. Players table is created in the onCreate() method thanks to a SQL statement.
In our class, we add methods to add a new player, to delete an existing one, to update and then a method to get all the players in the table. In this last method, we use a Cursor object to iterate on rows and then build equivalent Player instances.
To use our class to create some players then display on a simple ListView, we can use the following code :
Code:
public class MainActivity extends Activity {
private SQLiteDatabaseHandler db;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// create our sqlite helper class
db = new SQLiteDatabaseHandler(this);
// create some players
Player player1 = new Player(1, "Lebron James", "F", 203);
Player player2 = new Player(2, "Kevin Durant", "F", 208);
Player player3 = new Player(3, "Rudy Gobert", "C", 214);
// add them
db.addPlayer(player1);
db.addPlayer(player2);
db.addPlayer(player3);
// list all players
List<Player> players = db.allPlayers();
if (players != null) {
String[] itemsNames = new String[players.size()];
for (int i = 0; i < players.size(); i++) {
itemsNames[i] = players.get(i).toString();
}
// display like string instances
ListView list = (ListView) findViewById(R.id.list);
list.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, itemsNames));
}
}
}
Execution result can be seen here :
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
SQLite implementation in Android is simple and really powerful. You can now use it in your Android application to persist data.
Don't hesitate to give it a try and give me your feedbacks about this tutorial.
Thanks.
Sylvain
Hey, I have made a preview for SQLite database earlier this month for my friend.
If anyone's interested then it's there at https://www.GitHub.com/Fifa2151/SQLiteTest
Thanks,
Raj.
Sent from my Pixel using Tapatalk
sylsau said:
Hello,
I create that thread to present you a tutorial learning you to save data with SQLite on Android. This tutorial is also available in video on Youtube :
Learn to save data with SQLite on Android
On Android, there are several solutions to persist data between users’ sessions. One solution is to use a relational database to persist data and then to be able to query easily these data. In standard, Android SDK comes with a SQLite implementation. Biggest advantage of SQLite integration to Android OS is the fact that there is no need to to setup the database. So, no administration of this database. SQLite is embedded in standard and each application can have its SQLite database.
The only job that developers must make is to define SQL tables and statements for creating and updating data. Access to an SQLite database involves accessing the file system. So, it can be a slow operation. To avoid ANR (Application Not Responding) errors, it’s recommended to perform database operations asynchronously.
When an application creates and uses a SQLite database, it will be saved by default in the directory : DATA/data/APP_PACKAGE/databases/FILENAME .
1. Architecture
All classes needed to manage databases in Android SDK are contained in the package android.database . The package android.database.sqlite contains the SQLite specific classes.
SQLite API is centered around 2 main classes :
SQLiteOpenHelper that is an helper class to extend to manage database operations.
SQLiteDatabase that is the base class for working with a SQLite database in Android.
2. SQLiteOpenHelper
When you want to work with a SQLite database in Android, you must extend SQLiteOpenHelper class. In the constructor of your subclass you call the super() method of SQLiteOpenHelper, specifying the database name and the current database version.
You need also to override the following methods :
onCreate() that is called when database is accessed but not yet created.
onUpgrade() called when you choose to increment the version number of the database. In this method you can manage the migration process between two databases versions.
Both methods get and SQLiteDatabase instance in parameter which is the way to communicate with the database.
Furthermore, SQLiteOpenHelper provides 2 methods to get access to an SQLiteDatabase instance object respectively in read and in write modes :
getReadableDatabase() for read mode.
getWriteableDatabase() for write mode.
3. SQLiteDatabase
SQLiteDatabase is the class used to communicate with a SQLite database. It exposes several methods to interact with database like insert(), update() or delete().
In addition, it lets you to make queries via rawQuery() to queries made directly in SQL or via query() method. This last method provides a structured interface for specifying a SQL query.
4. Practice
Now, you know theory about SQLite in Android context. We can put in practice all the concepts. To achieve that, we’re going to make a database with a players table letting us to store NBA players.
To start, we create a simple Player Java POJO :
Code:
public class Player {
private int id;
private String name;
private String position;
private int height;
public Player() {
}
public Player(int id, String name, String position, int height) {
this.id = id;
this.name = name;
this.position = position;
this.height = height;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPosition() {
return position;
}
public void setPosition(String position) {
this.position = position;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
@Override
public String toString() {
return name + " - " + position + " - " + height + " cm";
}
}
Then, we must create the SQLiteOpenHelper extended class to manage our application database. Code is here :
Code:
package com.ssaurel.samples.sqlite;
import java.util.LinkedList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class SQLiteDatabaseHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "PlayersDB";
private static final String TABLE_NAME = "Players";
private static final String KEY_ID = "id";
private static final String KEY_NAME = "name";
private static final String KEY_POSITION = "position";
private static final String KEY_HEIGHT = "height";
private static final String[] COLUMNS = { KEY_ID, KEY_NAME, KEY_POSITION,
KEY_HEIGHT };
public SQLiteDatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
String CREATION_TABLE = "CREATE TABLE Players ( "
+ "id INTEGER PRIMARY KEY AUTOINCREMENT, " + "name TEXT, "
+ "position TEXT, " + "height INTEGER )";
db.execSQL(CREATION_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// you can implement here migration process
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
this.onCreate(db);
}
public void deleteOne(Player player) {
// Get reference to writable DB
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_NAME, "id = ?", new String[] { String.valueOf(player.getId()) });
db.close();
}
public Player getPlayer(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_NAME, // a. table
COLUMNS, // b. column names
" id = ?", // c. selections
new String[] { String.valueOf(id) }, // d. selections args
null, // e. group by
null, // f. having
null, // g. order by
null); // h. limit
if (cursor != null)
cursor.moveToFirst();
Player player = new Player();
player.setId(Integer.parseInt(cursor.getString(0)));
player.setName(cursor.getString(1));
player.setPosition(cursor.getString(2));
player.setHeight(Integer.parseInt(cursor.getString(3)));
return player;
}
public List<Player> allPlayers() {
List<Player> players = new LinkedList<Player>();
String query = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(query, null);
Player player = null;
if (cursor.moveToFirst()) {
do {
player = new Player();
player.setId(Integer.parseInt(cursor.getString(0)));
player.setName(cursor.getString(1));
player.setPosition(cursor.getString(2));
player.setHeight(Integer.parseInt(cursor.getString(3)));
players.add(player);
} while (cursor.moveToNext());
}
return players;
}
public void addPlayer(Player player) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, player.getName());
values.put(KEY_POSITION, player.getPosition());
values.put(KEY_HEIGHT, player.getHeight());
// insert
db.insert(TABLE_NAME,null, values);
db.close();
}
public int updatePlayer(Player player) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, player.getName());
values.put(KEY_POSITION, player.getPosition());
values.put(KEY_HEIGHT, player.getHeight());
int i = db.update(TABLE_NAME, // table
values, // column/value
"id = ?", // selections
new String[] { String.valueOf(player.getId()) });
db.close();
return i;
}
}
Database is created in the constructor of the extended class. Players table is created in the onCreate() method thanks to a SQL statement.
In our class, we add methods to add a new player, to delete an existing one, to update and then a method to get all the players in the table. In this last method, we use a Cursor object to iterate on rows and then build equivalent Player instances.
To use our class to create some players then display on a simple ListView, we can use the following code :
Code:
public class MainActivity extends Activity {
private SQLiteDatabaseHandler db;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// create our sqlite helper class
db = new SQLiteDatabaseHandler(this);
// create some players
Player player1 = new Player(1, "Lebron James", "F", 203);
Player player2 = new Player(2, "Kevin Durant", "F", 208);
Player player3 = new Player(3, "Rudy Gobert", "C", 214);
// add them
db.addPlayer(player1);
db.addPlayer(player2);
db.addPlayer(player3);
// list all players
List<Player> players = db.allPlayers();
if (players != null) {
String[] itemsNames = new String[players.size()];
for (int i = 0; i < players.size(); i++) {
itemsNames[i] = players.get(i).toString();
}
// display like string instances
ListView list = (ListView) findViewById(R.id.list);
list.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, itemsNames));
}
}
}
Execution result can be seen here :
SQLite implementation in Android is simple and really powerful. You can now use it in your Android application to persist data.
Don't hesitate to give it a try and give me your feedbacks about this tutorial.
Thanks.
Sylvain
Click to expand...
Click to collapse
Awesome guide @sylsau...
Also, do you know how to make a flashify type app but only for a specific zip?
When you want to work with a SQLite database in Android, you must extend SQLiteOpenHelper class. In the constructor of your subclass you call the super() method of SQLiteOpenHelper, specifying the database name and the current database version.
Click to expand...
Click to collapse
You don't actually need to use a subclass of SQLiteOpenHelper you can use the SQliteDatabase's open????? methods.
Furthermore, SQLiteOpenHelper provides 2 methods to get access to an SQLiteDatabase instance object respectively in read and in write modes :
Click to expand...
Click to collapse
Actually, in either case, except if the database cannot be opened, for write, both getReadableDatabase and getWritableDatabase will open a database that can be written to. As per :-
Create and/or open a database. This will be the same object returned by getWritableDatabase() unless some problem, such as a full disk, requires the database to be opened read-only. In that case, a read-only database object will be returned. If the problem is fixed, a future call to getWritableDatabase() may succeed, in which case the read-only database object will be closed and the read/write object will be returned in the future.
Click to expand...
Click to collapse
as per developer.android.com/reference/android/database/sqlite/SQLiteOpenHelper#getReadableDatabase()​
On occasions people new to SQLite sometimes wonder why no database exists after they have instantiated the subclass of SQLiteOpenHelper (aka the DatabaseHelper). This is because the database is only created when either getWritableDatabase or getReadableDatabase is called. With a single line added to the constructor, the constructor will create the database (and thus invoke the onCreate method) e.g.
Code:
public SQLiteDatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.getWritableDatabse();
}
AUTOINCREMENT is perhaps the most commonly misused keyword (perhaps wrongly named). It does not make the column automatically generate a unique ID. It is INTEGER PRIMARY KEY that does this, as it make the column an alias of the **rowid**.
Rather AUTOINCREMENT compliments INTEGER PRIMARY KEY adding a constraint that the generated ID must be larger that any ID that exists or have existed. However, this is a moot point as it's only when the largest possible ID has been assigned (9223372036854775807) that it comes into play (other than without AUTOINCREMENT a deleted highest ID will be resused). At this point a table with AUTOINCREMENT will then fail with an SQLITE_FULL exception (without AUTOINCREMENT will attempt to assign a free lower ID rather than fail). However, AUTOINCREMENT has overheads (using a limited test I came up with an 8-12% degradation in performance when inserting). This is due to a changed algorithm being used that utilises another table sqlite_sequence that stores the highest allocated ID.
The SQLite documentation states :-
The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, and disk I/O overhead and should be avoided if not strictly needed. It is usually not needed.
Click to expand...
Click to collapse
sqlite.org/autoinc.html
There are a few issues with the code, such as :-
You should always close Cursors when finished with them (not doing so may result in too many databases /database objects open exception ).
Checking a Cursor for null after a Cursor is returned from a call to an SQLiteDatabase method that returns a Cursor serves no purpose. A valid Cursor will always be returned. If there is no data then using a Cursor moveTo????? method will return false is the move cannot be made, alternately the getCount() method will return the number of rows in the Cursor.
If there were now rows in the Players table, the the code would fail with an error when an attempt is made to retrieve data at
Code:
player.setId(Integer.parseInt(cursor.getString(0)));
Issues regarding mis-calculated column offsets can be reduced by taking advantage of the Cursor's **getColumnIndex** method.
As such, as an example, the getPlayer method would be improved if changed to :-
Code:
public Player getPlayer(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_NAME, // a. table
COLUMNS, // b. column names
" id = ?", // c. selections
new String[] { String.valueOf(id) }, // d. selections args
null, // e. group by
null, // f. having
null, // g. order by
null); // h. limit
Player player = new Player(); //<<<<<<<<<< Always have a Player to return (should check for default player to indicated )
if (cursor.moveToFirst()) {
player.setId(Integer.parseInt(cursor.getString(cursor.getColumnIndex(KEY_ID))));
player.setName(cursor.getString(cursor.getColumnIndex(KEY_NAME)));
player.setPosition(cursor.getString(cursor.getColumnIndex(KEY_POSITION)));
player.setHeight(Integer.parseInt(cursor.getString(cursor.getColumnIndex(KEY_HEIGHT))));
}
cursor.close(); //<<<<<<<<<< Important to close a Cursor
return player;
}

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