[Q] Enumerate System Services? - Android Software Development

Is there any way to get a listing on a specific android device of what values are acceptable for the
Context.getSystemService()
method? And yes, I know that, in theory, the acceptable values are enumerated on the Context object, but that's not always the case.
For example, Sprint's Wimax service isn't. You have to specify the literal "wimax" to get the wimax manager, and that only works on the HTC phones, not the Samsung. Samsung phones return a null if you pass in "wimax".
Thanks,
Scott

No one knows, uh? bummer.

Try the following code:
Code:
Class serviceManagerClazz = Class.forName("android.os.ServiceManager");
Method listServices = serviceManagerClazz.getMethod("listServices");
String[] services = (String[]) listServices.invoke(null);

Thanks for responding. Unfortunately that doesn't work. listServices.invoke(null) returns null.
Thanks again,
Scott

That apparently doesn't work because the android.os.servicemanager is not a public class.

Related

TAPI weird problem with callerid

Hi Guys:
I'm having a weird problem with TAPI, basically I'm developing an app that intercepts incoming calls and then extract the callerid before starting recording the call.
I'm using WM 2005 and the device is an HTC Universal (T-Mobile MDA PRO) with a T-Mobile UK SIM.
All seems to work fine, the event loop receive the message(s) ,first receives an LINE_APPNEWCALL and then LINE_CALLINFO with dwParam1 set to LINECALLINFOSTATE_CALLERID, but when calling lineGetCallinfo to get the CallerID , the callerid flags (dwCallerIDFlags) returns 32 or "Unknow", even when the built-in alert in the phone is showing the caller id!
I killed cprog.exe from the process viewer (the phone didn't rang so the process was in fact killed) but not difference...Any ideas? Any tricks? Below a copy of the loop that I'm using:
void FAR PASCAL lineCallbackFunc(
DWORD hDevice,
DWORD dwMsg,
DWORD dwCallBackInstance,
DWORD dwParam1,
DWORD dwParam2,
DWORD dwParam3)
{
DWORD dwT = dwMsg;
LINECALLINFO *lpCallInfo;
size_t ci_size = sizeof(LINECALLINFO);
TCHAR *buffNum;
long Err;
OutputDebugString(_T("CB\n"));
switch (dwMsg){
case LINE_CALLINFO: {
switch(dwParam1)
{
case LINECALLINFOSTATE_CALLEDID:
{
OutputDebugString(_T("CALLID"));
break;
}
case LINECALLINFOSTATE_CALLERID:
{
OutputDebugString(_T("CALLERID"));
lpCallInfo = (LINECALLINFO *)calloc(ci_size,1);
lpCallInfo->dwTotalSize = ci_size;
Err = lineGetCallInfo((HCALL)hDevice,lpCallInfo);
if((DWORD)lpCallInfo->dwCallerIDFlags & (LINECALLPARTYID_ADDRESS | LINECALLPARTYID_PARTIAL)) {
_tcsncpy(buffNum, (LPTSTR)((BYTE*)lpCallInfo + lpCallInfo->dwCallerIDOffset), 256);
OutputDebugString(buffNum);
}
break;
}
break;
}
case LINE_APPNEWCALL:
{
OutputDebugString(_T("Newcall"));
// HCALL hCall = (HCALL)dwParam2;
break;
}
}
}
}
#define TAPI_API_LOW_VERSION 0x00020000
#define TAPI_API_HIGH_VERSION 0x00020000
#define EXT_API_LOW_VERSION 0x00010000
#define EXT_API_HIGH_VERSION 0x00010000
And here is how the TAPI starts: (in Main):
liep.dwTotalSize = sizeof(liep);
liep.dwOptions = LINEINITIALIZEEXOPTION_USEHIDDENWINDOW ;
if (lineInitializeEx(&hLineApp, 0, lineCallbackFunc, NULL,
&dwNumDevs, &dwAPIVersion, &liep))
{
goto cleanup;
}
OutputDebugString(_T("Init"));
// get the device ID
dwTAPILineDeviceID = GetTSPLineDeviceID(hLineApp, dwNumDevs,
TAPI_API_LOW_VERSION,
TAPI_API_HIGH_VERSION,
CELLTSP_LINENAME_STRING);
// error getting the line device ID?
if (0xffffffff == dwTAPILineDeviceID)
{
goto cleanup;
}
// now try and open the line
if(lineOpen(hLineApp, dwTAPILineDeviceID,
&hLine, dwAPIVersion, 0, 0,
LINECALLPRIVILEGE_MONITOR, dwMediaMode, 0))
{
goto cleanup;
}
// set up ExTAPI
if (lineNegotiateExtVersion(hLineApp, dwTAPILineDeviceID,
dwAPIVersion, EXT_API_LOW_VERSION,
EXT_API_HIGH_VERSION, &dwExtVersion))
{
goto cleanup;
Any help will be really helpfull, thanks.
Check your return value from lineGetCallInfo
check your return value from lineGetCallInfo. It will be LINEERR_STRUCTURETOOSMALL because lpCallInfo points to a buffer that's too small. (LINECALLINFO is a variably sized data structure) If you failed to make it large enough, you can allocate memory of size lpCallInfo->dwNeededSize and call lineGetcallInfo again. (look at documentation for lineGetCallInfo and LINECALLINFO)
Thanks for your reply, I checked the return value and is 0 so the size is fine (in fact dwSizeNeeded is greater than dwTotalSize so that is no problem), however I will change that bit just in case.
The interesting thing is that lpcallinfo structure returns "32" (UNKNOWN) for the dwCallerIDflags, even when the built-in notification program (cprog.exe) shows the callerid with no problem.
I even killled cprog.exe before testing and is the same, I wonder if there is something related with the Service Provider (T-Mobile) or some other setting that is interfering or no standard.
Any tip or suggestion is appreciated and welcome.
Thanks
Instead of testing the flag, test if dwCallerIDSize>0. Thats what I do. I have systematically gone through all values in the LINECALLINFO and most of them are zeroed out by the network regardless of what should be in them so I inclined to not trust it.
Also it could be your timing. Are you checking every time a LINE_CALLINFO/LINECALLINFOSTATE_CALLERID comes in or just once. The caller id is not always available on the first time but on subsequent messages is available.
Also it cant hurt to add extra memory to the LINECALLINFO. Just +1024 to be sure there is space for the caller id (or any other appended data before the caller id). You said dwSizeNeeded > dwTotalSize, that means you do not have enough memory and need to rellocate and call lineGetCallInfo again to refill the LINECALLINFO.
You do not need to kill the phone app (cprog.exe) to get caller id. It is a very bad idea to kill it without good reason. IMO the only valid reason to kill it would be to allow user interaction with your window during this time. There are side affects from killing cprog that can include uncontrollable vibration that requires a reset to stop if you have not prevented it programatically.
dwSizeNeeded is the amount needed to store the structure.
dwSizeTotal is the amount you provided.
if dwSizeNeeded > dwSizeTotal then there isn't enough room.
Are you sure that lineGetCallInfo returned 0?
If any of the dwXXXXSize members of LINECALLINFO struct are non-zero (which seams very likely), then you will need more than sizeof(LINECALLINFO) bytes.
I agree with OdeeanRDeathshead, no need to kill cprog. This will work without that. If I ever want to kill cprog, I usually replace cprog by a program with sleep(60*60*24) in a loop, then reboot. Or I replace it with the program I'm testing and reboot. On my phone, this doesn't seam to cause problems. If I just kill cprog, it will be restarted within a few minutes.
I also just check whether dwCallerIDSize > 0.
good luck
I you don't get it working, I was wondering if you could post your values for dwSizeTotal , dwSizeNeeded, and dwSizeUsed.
Thanks guys, you were totally rigth! The problem was that I was expecting the API (lineGetCallInfo) to return STRUCTURE_TOO_SMALL error and I didn't make any check on dwSizeNeeded.
Funny enough, the API returned no error at all and even the structure had some data on it, but it wasn't big enough, so basically I added a loop to check the Size and reallocate memory until is enough, it works like a charm now.
On a separate note, on outgoing calls I had to introduce a small delay, the CalledID information it doesn't become instantly, by testing in the HTC Universal seems to be slow on outgoing calls, I hope that wont be any trouble there.
Thanks again guys for your help, it saved me a lot of work.
This piece of code works on my iPAQ, but it does NOT work on a Treo 700wx. It retrieves no number on a Treo 700wx. Anybody face the same issue?
Your iPAQ is a pocket pc, and the treo is a smartphone. The smartphone has a two tier security model. ExTAPI is a privileged API, so on a smartphone it can only be run with by a trusted application. The application must be signed with a trusted certificate.
But why is the product specification advertised as "Pocket PC Phone Edition" (see http://www.palm.com/us/products/smartphones/treo700w/specs.html)
The treo 700wx is the US edition? Because the ones that I used in America had Windows Mobile 5.0 Pocket PC edition, however it sounds like a security issue as the guys mentioned above.
Take a look at :
http://msdn.microsoft.com/library/d.../wce51conWindowsMobileDeviceSecurityModel.asp
http://blogs.msdn.com/windowsmobile/archive/2005/11/03/488934.aspx
I signed the app by using the provided privileged certificate in the SDK and it works (in fact I used exTAPI), is worth to try.
Another thing, did you check the CALLERPARTYID flags to ensure that there is a "callerid" after calling getCallInfo?
And one curious thing about the Palms and Verizon, while we developed all in the UK , IMEI numbers are equally formated, in the US for some reason, both Motorola Q and Palm 700w got different formats, same for callerid sometimes, if you are doing any string operation after obtaining the number (like formating, etc,etc) be sure that is not causing any problem.
But my iPAQ is also running WM5 PPC Phone Edition. I believe the code provided above is in fact compatible with many WM5 phone devices, specifically HTC made devices like O2, Dopod, etc.
So is it because Treo 700w has special security level that we need to comply for TAPI to work properly?
Also, commands like lineInitialize, lineOpen, lineGetCallInfo does not return any error. The thing is this... same piece of code, runs on most WM5 PPC, able to retrieve incoming number. But there's just NO incoming number return on a Treo 700w/wx. Any idea?
arsenallad said:
...The treo 700wx is the US edition?...
...Another thing, did you check the CALLERPARTYID flags to ensure that there is a "callerid" after calling getCallInfo?...
Click to expand...
Click to collapse
Yes. Treo 700wx US edition.
No. I use dwCallerIDSize>0.
not sure why it's not working for you, I run simular code on an apache and a iPAQ 6215, works fine. However, I don't think it's a security problem. I was confused by palm calling the treo a smartphone. It has a touch pad, it must be a Pocket PC .
Pocket PC doesn't support the two tier model. Smartphone supports both models. If registry value HKLM\Security\Policies\Policies\0000101b is 0 then the device is two tier otherwise it's one tier. Note 0x101b=4123 so search MSDN for security policy 4123 to find out more.
Plus it's the tapi api that needs to work not exTapi. I don't think any of the tapi functions are privileged.
Just wanted to correct my mistake from yesterday. If you have VS2005 you might want to look at the CallInfo structure in the debuger.
Good luck
WangSN said:
Yes. Treo 700wx US edition.
No. I use dwCallerIDSize>0.
Click to expand...
Click to collapse
dwCallerIDSize it will tell you only the length, if for instance the structure is not properly initialized (as happened to me in this thread) dwCallerIDSize will be zero too, is not a good idea because doesn't give you too much info.
Check in your structure the dwCallerIDFlags member , if returns LINECALLPARTYID_ADDRESS or LINECALLPARTYID_PARTIAL means that callerid is there, now if LINECALLPARTYID_BLOCKED is returned is very likelly that the operator it doesn't have the callerid active or you are calling from a line that protects the "privacy" (whitheld) sometimes is the case, specially in offices that uses PBX.
If LINECALLPARTYID_UNKNOWN is returned, then probably you are having a problem either with the callerid service (the phone does show the callerid when calling?) or somethign to do with your lpcallinfo structure allocation, check that dwTotalSize >= than dwNeeded.
One more thing: It happens to me that after testing using an HP Phone I started testing in a HTC universal phone and it didn't work , particullary in outbound calls, for some reason the LINECALLPARTYID flag returned ADDRESS, but the structure was empty. After trying to discover what was going on, I introduced a small pause in the thread (Sleep) of 2 seconds and worked fine, it seems that hardware can be slow
Good luck.
Nope No luck in getting this to work...
Checked dwCallerIDFlags member, even when value is LINECALLPARTYID_ADDRESS|LINECALLPARTYID_PARTIAL still does not contain the incoming number.
Also tried Sleep for 2 seconds, but still NO number. Before the 2 seconds wait expires, the built-in PPC incoming call dialog already show up WITH caller number.
I'm running out of ideas...
problem solved, post edited...

HTC Sensors (HTCSensorSDK.dll)

Hi, I've seen some sensor implementations and some of them are not good written I think. I've disassembled HTCSensorSDK.dll file to help developers who use HTC sensors. You can look at it to know how it is done.
PF2009
I'm not a developer, but isn't this the same like this?
No, HTCSensorSDK.dll is SDK library from HTC which is used by this. 'Unified Sensor API' imports only some of HTCSensorSDK.dll functions. The author doesn't know how it was implemented. So there are some useless parts e.g.:
enum HTCSensor : uint
{
Something = 0, <--
GSensor = 1,
Light = 2,
Another = 3, <--
}
or signaling events:
// note: I noticed in Scott's code, on the shutdown he fires the "HTC_GSENSOR_SERVICESTART" event again.
// I am guessing that is a bug in his code.
// My theory is the service start/stop manage a reference count to the service.
// Once it hits 0, the service is stopped.
IntPtr hEvent = CreateEvent(IntPtr.Zero, true, false, "HTC_GSENSOR_SERVICESTOP");
SetEvent(hEvent);
CloseHandle(hEvent);
Awesome! You are correct, my implementation of the HTC sensor contains a lot of debug/instrumentation code. But it is private and unused, so it is really just benign code (such as the enum).
The only particular spot I wasn't sure was being done properly was the sensor cleanup; as indicated in my code comment. The only real outstanding issue then is the signaled events. I actually think that is used to start the HTC service that changes the orientation setting in the registry. So that is probably legitimate code. Unless you know otherwise?
The Samsung implementation was a lot easier, because I had a .h file to work with.

dynamically setting image resources

greetings
was referred to this forum from someone at androidcommunity.com regarding this...
i searched the forum but couldnt find any relevant posts - can anyone point me in the right direction for doing this properly?
specifically how could one set an image resource based on a string variable being used for part of the image's file name
i tried this based on a post i saw elsewhere:
myContext.getResources().getIdentifier(myStringVariable + "_thumbnail", "drawable", myContext.getPackageName()));
but it returnes a string(or an integer?) of numbers (the resource id?) that setImageResource couldnt use unless i just wasnt doing it properly.
is there perhaps a way to get the resource name based on that id number or whatever it is that im getting?
apreesh
33 views
dang
getIdentifier() returns int and yes, it could be used in setImageResource() method.
But why you want to set resources from strings?
because the image being set is based on user selection and is not just one image its several associated images so there is a number sequence to the image file names as well that i did not show in the snippet i posted.
but i went back and plugged some of those returned values (resources ids?) from getIdentifier() into setImageResource() and it does indeed work so thanks for that - i have an idea what i was doing wrong before but for the sake of moving on im using a different solution now - in short i am now defining each group of images as a separate class member int[] and i will probably use a switch case to plug the correct one into the gridview. its ugly, but i currently only have 11 different groups and no more than 16 images per group so it will work for now until i can study the resource object more and figure out a way to get counts of associated image resources based on a part of the resource name, like with a regular expression or something, because thats the next problem i will have to deal with if i am not pre-defining all of these arrays.
if you know of a way to do that that would be awesome but ill will probably look into it more myself once i get this app closed up and can go back and fix stuff. im pressed for time right now.
thanks
It's really bad thing to use getIdentifier() method, we should always use R class. I think your problem resides somewhere before, you try to do something, that you shouldn't
How do you get these strings? You mentioned they are from user, but he doesn't write them by hand, right? If this is some selectable list, etc., they should be ints, enums, or some objects from the beginning. Not strings. Parsing strings is always ugly.
Ahh and if you have group of many small images, it is usually better to concatenate them into one big image - it's more efficient and you don't have to use 200 R constants in your code.
the string comes from the tag associated with a clickable imageView selected from the previous screen - a menu item if you will. the string will serve several purposes, retrieving related data, etc, but the first thing i needed to work out was retrieving the correct images and displaying them. i dont know how i could concatenate the images into one big image because each one needs to be clickable itself and handle certain events associated with itself.
i will go ahead and admit this is my first app so im basically figuring stuff out as i go. and learning most of my oop from flash has probably handicapped me
i appreciate your help dude
Brut.all said:
it's more efficient and you don't have to use 200 R constants in your code.
Click to expand...
Click to collapse
the only other thing i could think of trying was creating an xml doc to group the associated resource names together and figure out how to read from that to know which images to set
i dont see any methods in the R class i could use for sorting, grouping and then retrieving certain resources based on user interaction
switch cant eval string types...!?
kadmos said:
switch cant eval string types...!?
Click to expand...
Click to collapse
Nope
As I said, strings aren't good for identifying things - regardless of the language used. This is why people created int constants and/or enums.
And no, I doubt there are some mechanisms of grouping resources, etc. It must be simple, you are trying to complicate everything
I have a strong feeling that you should change your app architecture and get rid of strings. But here quick general fix (not a good solution! but just works).
Map your strings to R ints:
Code:
Map<String, Integer> map = new HashMap<String, Integer>();
map.put("button_normal", R.drawable.button_normal);
map.put("button_pressed", R.drawable.button_pressed);
// etc
Accessing will be done:
Code:
map.get("button_" + state); // Return int id, use as you need.
This is a bad practice, but it will work. Consider re-archirecturing your app.
@Brut.all: do you have any plans on updating apktool with 2.2 support?
@kadmos
Full example:
Code:
public static enum Planet {
MERCURY(R.string.planet_mercury, R.drawable.planet_mercury),
VENUS(R.string.planet_venus, R.drawable.planet_venus),
EARTH(R.string.planet_earth, R.drawable.planet_earth),
MARS(R.string.planet_mars, R.drawable.planet_mars);
public final int nameResId;
public final int imageResId;
public static Planet findByNameResId(int nameResId) {
for (Planet p : values()) {
if (p.nameResId == nameResId) {
return p;
}
}
return null;
}
private Planet(int nameResId, int imageResId) {
this.nameResId = nameResId;
this.imageResId = imageResId;
}
}
You have enum of planets, each of them has its name and image. Then you could do something like:
Code:
@Override
public boolean onCreateOptionsMenu(Menu menu) {
for (Planet planet : Planet.values()) {
menu.add(0, planet.nameResId, 0, planet.nameResId);
}
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
Planet planet = Planet.findByNameResId(item.getItemId());
doSomethingWithPlanetImage(planet.imageResId);
return true;
}
You identifies planets by ints (nameResId in this example - of course it must be unique), not by strings. Operations on ints are several times faster, than on strings, this is why Google decided to identify all things: resources, menu items, etc. just by ints.
Ahh and no, writing switch-cases to do something depending on given object isn't true OOP. OOP is above: enums know, which drawable is connected to them, there is no need for switches.
AuxLV said:
@Brut.all: do you have any plans on updating apktool with 2.2 support?
Click to expand...
Click to collapse
Yeah, of course, I want to work on apktool this weekend. Unfortunately baksmali doesn't support Froyo yet, so I can't support it fully neither.
@Brut.all:
Ha, I recognise that example It's from the Java Trail/tutorial on enums isn't it? Except they used gravity rather than drawable references.
@kadmos:
Are all the images known from the beginning? In other words, is the user creating them at runtime or are you including them with your app? If they are included with your APK then normally, as Brut said, you should be able to use the identifiers directly.
Concatenating the images all into one isn't hard to do, as you can still draw the specific bitmaps out using the Bitmap.create(bitmapToGetAPartOutOf, ....) method. You can then make those individual bitmaps into ImageViews and only have to remember the 'grid reference' for where they came out of the big image. That said, you'd have to balance the added complexity of creating the big images against the ease of not having loads of R constants. I can't really say anymore because I'm not fully following what you're trying to achieve.
Steven__ said:
@Brut.all:
Ha, I recognise that example It's from the Java Trail/tutorial on enums isn't it? Except they used gravity rather than drawable references.
Click to expand...
Click to collapse
I took planets example, because it's good, but everything was written from scratch
Steven__ said:
Concatenating the images (...)
Click to expand...
Click to collapse
I'm pretty sure I saw this concatenating approach somewhere in official Android's guidelines for performance, but now I can't find it :-/ Also I don't have much experience in Android development, so if no one else suggest this approach, then I think kadmos could forget about it.
Brut.all said:
You identifies planets by ints (nameResId in this example - of course it must be unique), not by strings. Operations on ints are several times faster, than on strings, this is why Google decided to identify all things: resources, menu items, etc. just by ints.
Ahh and no, writing switch-cases to do something depending on given object isn't true OOP. OOP is above: enums know, which drawable is connected to them, there is no need for switches.
Click to expand...
Click to collapse
i know its not true oop i didnt want to have to do that but i have not yet seen a way to pass any value from a selected item into a method that could use that value to retrieve x amount of associated resources (images in this case).
Steven__ said:
Are all the images known from the beginning? In other words, is the user creating them at runtime or are you including them with your app? If they are included with your APK then normally, as Brut said, you should be able to use the identifiers directly.
...I can't really say anymore because I'm not fully following what you're trying to achieve.
Click to expand...
Click to collapse
using the planets example, say i had x (varying) amount of pics of each planet's surface in my drawables and wanted only those planet's pics to display in a grid view when a user selects whichever planet. thats really all this is. being new to this i just dont know the most efficient way to do it. if this was Flash i could just group all the images file names/paths in an external xml doc and use that to load them from whatever folder at runtime - i wouldnt need any of those 200 or so images declared as anything or even as assets in my library (and i would only need the xml because flash cant access a file system on its own to see and filter files that it would or wouldnt need based on, say, a string comparison - though there is third party software like Zinc that gives Flash that capability.)
so i did get this to work by passing a number as a tag (string) in a bundle though an imageView click event and then casting the string as an int to use in the switch - which as of now leads to one of 11 different int arrays of resources names (images) ive got declared in my ImageAdapter class to populate my gridView.
the way i wished i could made this work would have been to use a string (like a planet name) ,passed from whatever planet image/menu item/whatever was clicked, and use that string to compare and determine which and how many images in drawables were associated with that planet and then use that to create my gridView at runtime.
kadmos said:
so i did get this to work by passing a number as a tag (string) in a bundle though an imageView click event and then casting the string as an int to use in the switch - which as of now leads to one of 11 different int arrays of resources names (images) ive got declared in my ImageAdapter class to populate my gridView.
Click to expand...
Click to collapse
I see what you're saying, that makes sense. Just as a quick note though, if you're declaring your ImageViews programmatically, you don't have to use a string object for the tag. You can directly give the integer and then cast it back when you get the tag. Just remember to use (Integer) as the tag is actually just an unspecified object.
kadmos said:
the way i wished i could made this work would have been to use a string (like a planet name) ,passed from whatever planet image/menu item/whatever was clicked, and use that string to compare and determine which and how many images in drawables were associated with that planet and then use that to create my gridView at runtime.
Click to expand...
Click to collapse
Yes, I can see why you'd want to do it this way. Your current problem is that if you add more images, you have to manually update your arrays. Unfortunately I can't think of a better, 'clean' way of doing it.
@kadmos
Now I have problems understanding you ;-) But if you don't want to declare all images in sources, but in XMLs, then you could use XML arrays.
Code:
<resources>
<string-array name="planet_names">
<item>mercury</item>
<item>venus</item>
<item>earth</item>
<item>mars</item>
</string-array>
<integer-array name="planet_images">
<item>@array/mercury_images</item>
<item>@array/venus_images</item>
<item>@array/earth_images</item>
<item>@array/mars_images</item>
</integer-array>
<integer-array name="mercury_images">
<item>@drawable/mercury_0</item>
<item>@drawable/mercury_1</item>
<item>@drawable/mercury_2</item>
</integer-array>
<integer-array name="venus_images">
<item>@drawable/venus_0</item>
<item>@drawable/venus_1</item>
<item>@drawable/venus_2</item>
</integer-array>
<integer-array name="earth_images">
<item>@drawable/earth_0</item>
<item>@drawable/earth_1</item>
<item>@drawable/earth_2</item>
</integer-array>
<integer-array name="mars_images">
<item>@drawable/mars_0</item>
<item>@drawable/mars_1</item>
<item>@drawable/mars_2</item>
</integer-array>
</resources>
When user will open planet selector, you will iterate through contents of R.array.planet_names array, each item (planet) in this selector will have itemId set to array index. When user will click on something, you will get itemId of clicked item, then you will find array of its images as R.array.planet_images[itemId] (not exactly - it's conceptual example).
You will be able to add new images or even planets through XML editing.
Steven__ said:
Yes, I can see why you'd want to do it this way. Your current problem is that if you add more images, you have to manually update your arrays. Unfortunately I can't think of a better, 'clean' way of doing it.
Click to expand...
Click to collapse
Brut.all said:
But if you don't want to declare all images in sources, but in XMLs, then you could use XML arrays...
...You will be able to add new images or even planets through XML editing.
Click to expand...
Click to collapse
as i posted earlier this was the idea that i had - i havent tried it yet because i wanted to get some feedback from you guys just to see if i was completely off base. so right now its coming down to what would make for the more memory efficient final product - declaring all these images as class array constants (which i already have working) or using xml and coding the operations for parsing, counting, filtering, assigning, etc?
again thank you guys for your time and help
kadmos said:
or using xml and coding the operations for parsing, counting, filtering, assigning, etc?
Click to expand...
Click to collapse
Do you mean parsing XMLs? My example above uses standard Android resources. You don't have to parse these XMLs, you will get them as arrays And yes, it's super efficient, because they are compiled to easy-to-read form
ok then im going to go ahead and try it
be back soon
i hope

DataManagement Library for Easy Android Database Storage

Storing objects to a Database for an Android application should be fast and easy as:
Code:
dm.add(new StorableClass());
DataManagement is a new open source library that allows you to do just that.
DataManagement is a Java Android library designed to help easily and efficiently store aggregate classes to an SQLite database. It eliminates the need to write separate classes to manage database – object interactions and allows developers to use simple methods to store, query, update, and delete objects. The library is capable of storing all objects of classes whose instance variables are either primitive data types or are themselves objects of another storable class. The DataManagement Library condenses many standard database features into several simple methods. It is fully open source and the code can be found at http://epsilonlabsllc.github.com/DataManagement
Examples:
Creating a Storable Class:
Code:
public class StorableClass{
@Id
private int ident;
private int num1;
private double num2;
private String num3;
private boolean num4;
public static final int num5 = 3;
private OtherStorableClass[] ds2;
}
A storable class must meet two requirements. First, the class must have a private instance variable of type int that will be used as the id number of the object. This variable may be read by the application, but the application should not have the capability to write to or change this variable in anyway. This variable is identified by the system with an @Id annotation. In addition, the class should not have any instance variables that are not either primitive types, strings, or other storable objects.
Instantiating a DataManager Object:
Code:
DataManager dm = new DataManager(context);
The open method accepts the calling Context that is going to use the database. Usually this should be the calling Activity.
Opening a Database for Use:
Code:
dm.open();
This method must be called before the database is used in any way.
Closing a Database After Use:
Code:
dm.close();
This method should be called after all database operations have been performed.
Adding an Object to the Database:
Code:
int id = dm.add(new StorableClass());
The add method accepts an object of a storable class as its only parameter and adds it to the database. It returns its id in the database for future use.
Retrieving a Specific Item from the Database by ID:
Code:
StorableClass storableObject = dm.get(StorableClass.class, id);
The get method accepts two parameters: the data type of the stored object and the Id number of the object (the return value of the add method).
Retrieving All Objects of a Given Type Stored in the Database as a Collection:
Code:
storableObjectCollection = dm.getAll(StorableClass.class);
The getAll method’s only parameter is the class of the objects that should be retrieved.
Retrieving a Collection of Storable Objects that match a given criteria:
Code:
Collection<StorableClass> storableObjectCollection = dm.find(StorableClass.class, 5, "num1");
The find method accepts three parameters: the data type of the stored object, the value that is being searched for, and the name of the instance variable as a string. This method is overloaded in such a way that the second parameter may be any primitive value or a string.
Updating an Object in the Database:
Code:
dm.update(id, updatedObject);
The update method accepts two parameters: The id number of the object being updated and the updated object that will replace the existing one I the database. If the id number of the new object and the id number given as the first parameter do not match, the object’s id will be overwritten.
Deleting an Object by its Id number:
Code:
dm.delete(StorableClass.class, id);
The delete method accepts two parameters: The data type and id number of the object to be deleted.
Additional Notes:
Id numbers are used by the database to ensure that objects are put in the correct place and to allow the program to access these objects. It is important that programs using this library do not attempt to set these variables as they will be initialized and managed by the library. These id numbers are unique for objects of a given type; objects of different types may have the same id number. In addition, if objects are deleted from the database their id numbers are left empty and are not reused.
Licensing:
DataManagement is Currently Licensed under the GNU General Public License, version 3 (GPL-3.0). It is intended for open source use by anyone who would like to use it.
This is awesome!!
Tried it out for an app today-- incredibly simple! For those looking-- this library essentially replaces loads of SQL helper classes and queries with an interface that's similar to ArrayList.
Definitely going to use this for everything in the future!
Thanks
Did you change the license or something? The repo is no longer on github.
regaw_leinad said:
Did you change the license or something? The repo is no longer on github.
Click to expand...
Click to collapse
After a quick search on github, it looks like it's been moved here
https://github.com/epsilonlabsllc/DataManagement
cmike21 said:
After a quick search on github, it looks like it's been moved here
https://github.com/epsilonlabsllc/DataManagement
Click to expand...
Click to collapse
Thanks. I forgot to change it. I just edited my post with the correct url.
Sounds awesome! Great work.
Gonna try it this evening.
Anyone compared the performance with db4o?
are there any performance test with other DB libraries for android? and what about the this lib vs contentproviders?
activeandroid.com
code.google.com/p/orm-droid]orm-droid
satyan.github.com/sugar/
will definitly be using this once i learn some app development! thanks for this!
Just in time...
Hello,
I'm trying to build a simple project the test and learn how this lib works, but I'me quite new in programming and I have some difficulties to understand how to use dm.
The project will be a simple song database with edittexts for song and artist. I created the storableClass as the example, but I cannot understand how to connect it with the main activity, so I can use the output of the editTexts.
1st question is: do I need to have the String variables as private? I'm thinking that must have them as public, so I can connect them with the editTexts output.
2nd: question: all these methods needed to be called from storableClass, or from main activity, after I connected the storableClass with main activity? And how I do this?
Probably with the use of context you descibed, but I cannot understand how to do it. I tried sometimes but always get errors and a specific one "The constructor DataManager(Context) is not visible".
Is there any example project' source code which use this lib to get an Idea, or can you explain the context step more extensively?
Thanks in advance and sorry for noob questions.
dancer_69 said:
Hello,
I'm trying to build a simple project the test and learn how this lib works, but I'me quite new in programming and I have some difficulties to understand how to use dm.
The project will be a simple song database with edittexts for song and artist. I created the storableClass as the example, but I cannot understand how to connect it with the main activity, so I can use the output of the editTexts.
1st question is: do I need to have the String variables as private? I'm thinking that must have them as public, so I can connect them with the editTexts output.
2nd: question: all these methods needed to be called from storableClass, or from main activity, after I connected the storableClass with main activity? And how I do this?
Probably with the use of context you descibed, but I cannot understand how to do it. I tried sometimes but always get errors and a specific one "The constructor DataManager(Context) is not visible".
Is there any example project' source code which use this lib to get an Idea, or can you explain the context step more extensively?
Thanks in advance and sorry for noob questions.
Click to expand...
Click to collapse
Here is a sample project: https://github.com/epsilonlabsllc/D.../net/epsilonlabs/datamanagementefficient/test
(It's in the github project.)
You can set the strings on private, because you can grab the values of the edittext on your layout. Eclipse should generate your set/ get methods if you create your private strings. The methods. Take the values and insert them into your db, Look at the sample:
Code:
public DataSample(){
num1 = 3;
numderp = 3.0;
num3 = "three";
num4 = true;
ds2depier = new ArrayList<DataSample2>();
ds2depier.add(new DataSample2());
ds2depier.add(new DataSample2());
}
That is the basic constructor of the DataSample class. If you do an insert like
int id = dm.add(new StorableClass());
Click to expand...
Click to collapse
The basic constructor will be called and it sets your values for example the num1 =3. You could overwrite the basic constructor with your costum constructor to insert your values.
You activity call:
dm.add(DataSample(sSong,sTitle));
Click to expand...
Click to collapse
The constructor could be something like this:
public DataSample(String sSong, String sTitle){
sYourTitleDataBaseColumnCaption = sTitle;
sYourSongDataBaseColumnCaption = sSong;
}
Click to expand...
Click to collapse
Or use the set/get methods, my custom constructor are just an idea to show you an example. Just take a closer look at the github sample and it should work for you.
Thanks, I think I can figure it out now.
How to is very outdated. I can't initialize via new DataManager() but via getInstance(), also delete and update method doesn't have Id argument anymore.
Also,
I can't get this to work. I can't even add a member to collection because it needs to use db.add(new MyClass()); but i already have MyClass() initialized with their members. I have tried to do something like copy the Id from add, update into my other instance of this class and run a db.update() but it throws a RuntimeException.
Not usable at this time.
Sounds good!
I'll give it a try as soon as I start a new project that requires data storage ...
I really hate SQLiteOpenHelper, cursor and all this strange syntax ...
The idea is good, but it can't be compared to db4o, specially when talking about documentation.
Hello mate,
I'd like to use your library and backup the data with Google/Dropbox Sync... can you tell me the name of the file on which you save data?
Thanks,
Tiwiz

File transfer over TCP sockets

I've been trying to get a simple file transfer between desktop app and phone app. The transfer works up to a point, when it simply ...stops dead.
The server(aka desktop client) enters the listening state, and the phone goes idle.
Anyone has any samples on transfers of large file (bigger than 1 MB)?
mcosmin222 said:
I've been trying to get a simple file transfer between desktop app and phone app. The transfer works up to a point, when it simply ...stops dead.
The server(aka desktop client) enters the listening state, and the phone goes idle.
Anyone has any samples on transfers of large file (bigger than 1 MB)?
Click to expand...
Click to collapse
Have you looked through GoodDayToDie's source code for the File Server? I wonder if he has anything in there that could make that work.
snickler said:
Have you looked through GoodDayToDie's source code for the File Server? I wonder if he has anything in there that could make that work.
Click to expand...
Click to collapse
lalz.
Completely forgot about that one xD
Meh he has it written in C++
Apparently, he didn't do anything that I didn't.
mcosmin222 said:
lalz.
Completely forgot about that one xD
Meh he has it written in C++
Click to expand...
Click to collapse
You can still utilize the transfer portion . I was thinking of seeing what I could do with sockets on the phone. I know it could come in handy somehow
snickler said:
You can still utilize the transfer portion . I was thinking of seeing what I could do with sockets on the phone. I know it could come in handy somehow
Click to expand...
Click to collapse
It's a pain in the ***.
It stops transfer at random points.
mcosmin222 said:
It's a pain in the ***.
It stops transfer at random points.
Click to expand...
Click to collapse
That doesn't surprise me at all for some reason.
Did you double-check your socket multithreading code?
I recently had problems with sockets and it turned out that I had the muti-threading thing wrong.
I think you shouldn't use only one connection and fail if it drops ...
ScRePt said:
Did you double-check your socket multithreading code?
I recently had problems with sockets and it turned out that I had the muti-threading thing wrong.
I think you shouldn't use only one connection and fail if it drops ...
Click to expand...
Click to collapse
What do you mean by socket multthreading code? You mean the use of async methods? or having the thread work on background, using the socket?
Take a look to the Tim Laverty's networking samples.
sensboston said:
Take a look to the Tim Laverty's networking samples.
Click to expand...
Click to collapse
That's what im doing (more or less)
@mcosmin222: The most common reason I saw for why that happened was the thread doing the transfer would crash. There's a lot of things that could cause such a crash, but because it's not the main thread or a UI thread, you don't see it. It just stops. In fact, even the debugger usually doesn't catch it (annoying as hell...)
There are a few common things that non-UI threads aren't allowed to do which you might be trying. For example, attempting to show a MessageBox on a non-UI thread will crash the thread (you can do it by adding a lambda or function to the dispatcher for the UI). In any case, feel free to use or adapt my code, or share yours here and if there's an obvious issue I'll point it out. Incidentally, you can set a larger buffer on the socket if you want the operation to complete without looping.
By the way, the only portion of my webserver that's written in C++ is the file I/O code, which I chose to do in C++ rather than .NET because the phone's stunted .NET framework makes it more difficult than I like to access arbitrary file paths. That code is all fairly clean wrappers around the Win32 calls; I suppose I could comment it more but it's very straightforward to read even if you aren't familiar with managed C++. The actual network code is entirely written in C# 4.5. You could actually simplify it a bit for a direct transfer app, too; I wrote it with a lot of multithreading in case I wanted to re-use the code somewhere that might be expected to have more than one client connecting at a time.
GoodDayToDie said:
@mcosmin222: The most common reason I saw for why that happened was the thread doing the transfer would crash. There's a lot of things that could cause such a crash, but because it's not the main thread or a UI thread, you don't see it. It just stops. In fact, even the debugger usually doesn't catch it (annoying as hell...)
There are a few common things that non-UI threads aren't allowed to do which you might be trying. For example, attempting to show a MessageBox on a non-UI thread will crash the thread (you can do it by adding a lambda or function to the dispatcher for the UI). In any case, feel free to use or adapt my code, or share yours here and if there's an obvious issue I'll point it out. Incidentally, you can set a larger buffer on the socket if you want the operation to complete without looping.
By the way, the only portion of my webserver that's written in C++ is the file I/O code, which I chose to do in C++ rather than .NET because the phone's stunted .NET framework makes it more difficult than I like to access arbitrary file paths. That code is all fairly clean wrappers around the Win32 calls; I suppose I could comment it more but it's very straightforward to read even if you aren't familiar with managed C++. The actual network code is entirely written in C# 4.5. You could actually simplify it a bit for a direct transfer app, too; I wrote it with a lot of multithreading in case I wanted to re-use the code somewhere that might be expected to have more than one client connecting at a time.
Click to expand...
Click to collapse
I am aware that some calls from background threads are not allowed, especially those that have to do with the UI thread.
This is the code for the server. It would seem this one is the problem, somewhere...I just can't see where...
I tried limiting the number of packages sent (that's what the timer is all about).
Code:
public class StateObject
{
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 1024;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder();
}
public class AsynchronousSocketListener
{
// Thread signal.
public static ManualResetEvent allDone = new ManualResetEvent(false);
public static string[] TransferStages = new string[] { "sendmetadataz-length", "sendmetadataz", "file-length", "file" };
public static int Index = -1;
public static List<string> FilePaths = new List<string>();
public static long CurrentStreamPosition = 0;
public static FileStream ifs;
static int pocketspersecond = 0;
static bool LimitExceded = false;
DispatcherTimer timer = new DispatcherTimer();
public static int CurrentArraySize = 0;
public static int FileIndex = 0;
public AsynchronousSocketListener()
{
timer.Interval = TimeSpan.FromSeconds(1);
timer.Tick += timer_Tick;
}
void timer_Tick(object sender, EventArgs e)
{
LimitExceded = false;
}
public static void StartListening()
{
// Data buffer for incoming data.
byte[] bytes = new Byte[StateObject.BufferSize];
// Establish the local endpoint for the socket.
// Note: remember to keep the portnumber updated if you change
// it on here, or on the client
IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Any, 13001);
// Create a TCP/IP socket.
Socket listener = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp);
// Bind the socket to the local endpoint and listen for incoming connections.
try
{
listener.Bind(localEndPoint);
listener.Listen(10);
while (true)
{
// Set the event to nonsignaled state.
allDone.Reset();
// Start an asynchronous socket to listen for connections.
Console.WriteLine("Waiting for a connection...");
listener.BeginAccept(
new AsyncCallback(AcceptCallback),
listener);
// Wait until a connection is made before continuing.
allDone.WaitOne();
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
Console.WriteLine("\nPress ENTER to continue...");
Console.Read();
}
public static void AcceptCallback(IAsyncResult ar)
{
// Signal the main thread to continue.
allDone.Set();
// Get the socket that handles the client request.
Socket listener = (Socket)ar.AsyncState;
Socket handler = listener.EndAccept(ar);
// Create the state object.
StateObject state = new StateObject();
state.workSocket = handler;
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
public static void ReadCallback(IAsyncResult ar)
{
String content = String.Empty;
// Retrieve the state object and the handler socket
// from the asynchronous state object.
StateObject state = (StateObject)ar.AsyncState;
Socket handler = state.workSocket;
// Read data from the client socket.
int bytesRead = handler.EndReceive(ar);
if (bytesRead > 0)
{
// There might be more data, so store the data received so far.
state.sb.Append(Encoding.UTF8.GetString(
state.buffer, 0, bytesRead));
// Check for end-of-file tag. If it is not there, read
// more data.
content = state.sb.ToString();
if (content.IndexOf("<EOF>") > -1)
{
// All the data has been read from the
// client. Display it on the console.
Console.WriteLine("Read {0} bytes from socket. \n Data : {1}",
content.Length, content);
// Respond to the client
Send(handler, content);
}
else
{
// Not all data received. Get more.
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
}
public static void Send(Socket handler, String data)
{
//handler.SendBufferSize = File.ReadAllBytes(@"D:\MUZICA\Activ - Visez.mp3").Length;
// handler.BeginSendFile(@"D:\MUZICA\Activ - Visez.mp3", new AsyncCallback(SendCallback), handler);
#region cotobatura
data = data.Replace("<EOF>", "");
if (data.Contains("sendmetadataz") && data.Contains("length")==false)
{
data = MainWindow.DataContextModel.Files.ElementAt(FileIndex).ToString()+"<EOF>";
byte[] byteData = Encoding.UTF8.GetBytes(data);
// Begin sending the data to the remote device.
handler.BeginSend(byteData, 0, byteData.Length, 0,
new AsyncCallback(SendCallback), handler);
}
else if (data.Contains("sendmetadataz-length"))
{
Index++;
if (Index >= MainWindow.DataContextModel.Files.Count)
{
//FileIndex++;
data = "TransfersComplete<EOF>";
}
data = Encoding.UTF8.GetByteCount((MainWindow.DataContextModel.Files.ElementAt(FileIndex).ToString() + "<EOF>").ToString()).ToString();
byte[] MetaDataLength = Encoding.UTF8.GetBytes(data);
handler.SendBufferSize = MetaDataLength.Length;
handler.BeginSend(MetaDataLength, 0, MetaDataLength.Length, 0, new AsyncCallback(SendCallback), handler);
}
else if (data.Contains("file-length"))
{
ifs = File.Open(MainWindow.DataContextModel.Files.ElementAt(FileIndex).Location, FileMode.Open);
byte[] gugu = Encoding.UTF8.GetBytes(ifs.Length.ToString());
handler.SendBufferSize = gugu.Length;
handler.BeginSend(gugu, 0, gugu.Length, 0, new AsyncCallback(SendCallback), handler);
}
else if (data.Contains("file") && data.Contains("length") == false)
{
//byte[] filedata = File.ReadAllBytes(MainWindow.DataContextModel.Files.ElementAt(FileIndex).Location);
//handler.BeginSend(filedata, 0, filedata.Length, 0,
//new AsyncCallback(SendCallback), handler);
byte[] filedata = new byte[150];
for (int i = 0; i < 150; i++)
{
if (CurrentStreamPosition < ifs.Length)
{
filedata[i] = (byte)ifs.ReadByte();
CurrentStreamPosition++;
CurrentArraySize++;
}
else
{
Array.Resize(ref filedata, CurrentArraySize);
break;
}
CurrentArraySize = 0;
}
// if (pocketspersecond == 25) LimitExceded = true;
//Thread.Sleep(1000);
handler.BeginSend(filedata, 0, filedata.Length, 0, new AsyncCallback(SendCallback), handler);
}
//handler.BeginSendFile(MainWindow.DataContextModel.Files.ElementAt(FileIndex).Location, filedata, null, TransmitFileOptions.ReuseSocket, new AsyncCallback(SendCallback), handler );
// What we want to send back in this application is a game move based on what
// has been received. So we call Play on the GameLogic to give us a move to send back
// data = GameLogic.Play(data);
// Convert the string data to byte data using ASCII encoding.
//byte[] byteData = Encoding.UTF8.GetBytes(data);
// Begin sending the data to the remote device.
//handler.BeginSend(byteData, 0, byteData.Length, 0,
// new AsyncCallback(SendCallback), handler);
#endregion
}
public static void SendCallback(IAsyncResult ar)
{
try
{
// Retrieve the socket from the state object.
Socket handler = (Socket)ar.AsyncState;
// Complete sending the data to the remote device.
int bytesSent = handler.EndSend(ar);
Console.WriteLine("Sent {0} bytes to client.", bytesSent);
handler.Shutdown(SocketShutdown.Both);
handler.Close();
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
}
This is basically modified from the tick tak toe over sockets sample from MSDN.
The only possible call that would affect the UI is the call to the Console, but the code works fine for a while, after it just crashes.
I tried running the whole thing synchronously on the UI thread, the result appears to be the same.
In the Send method, the first 3 stages work (file-legth, metadata, metadata-length) and a few steps in the file stage (which actually sends the file).
AT some point, I assumed the thread was guilty somehow, but I just can't prove it. Running the thing directly on UI thread does not seem to change anything.
If the async method finishes and the socket gets disposed, the thread would "die".
PS: the entire thing is hosted by a WPF application.
Hmm... OK, there are several bugs here. I'm not sure which, if any, are responsible for the problem. I'd be tempted to overuse try-catch-log (for example, on the Send() function) and debug-print statements, but here are some things I can see that could cause a crash or other unexpected failure:
There is no guarantee that "ifs" is instantiated before use. If you for some reason skip the file-length step, the file step will crash with a null pointer exception.
The entire send function is hugely thread-unsafe. For example, if a second request arrives before you're done servicing the first one (which is entirely possible due to where the event gets signaled) then the values of "ifs" and "CurrentStreamPosition" and so on will be unpredictable at any given time. Since CurrentStreamPosition seems to be monotonically increasing, that's probably not going to cause an out-of-bounds exception, but it could cause you to enter a state where the test "if (CurrentStreamPosition < ifs.Length)" always fails.
The line "data = "TransfersComplete<EOF>";" never does anything; the next line (immediately following it) overwrites that variable. If you cared about that string, too bad.
FileIndex never changes; I hope you're only ever sending one file here...
You don't actually check that the number of bytes sent is the number you meant to send (admittedly, it *should* be, but there are cases where it won't be).
The last 150-byte chunk of every file transfer is truncated to the first byte. This is because "CurrentArraySize" is reset to 0 on every iteration of the byte-read loop (why use a byte-read loop?) so whenever "CurrentStreamPosition < ifs.Length" tests false, the "filedata" array will be resized to one byte (or zero if the file is an exact multiple of 150 bytes, which presumeably be correct).
There are probably more, but that's what jumped out at me (well, and some technically correct stylistic issues, like the "... == false" test). Given that your protocol seems to rely on end-of-message flags, I'm guessing that your problem is that since the last part of the file is almost always truncated, that marker is never getting sent. This probably leads to the client concluding that the server will be sending it more data, which it does by sending another "file" request. The server attempts to respond and immedately hits the CurrentStreamPosition < ifs.Length check, fails, goes to the else case, and tries to send a 1-byte packet containing a NULL byte.
Incidentally, does your file transfer protocol really require that the client request each 150-byte chunk one at a time, using a new TCP connection each time? That's... awfully inefficient.
GoodDayToDie said:
Hmm... OK, there are several bugs here. I'm not sure which, if any, are responsible for the problem. I'd be tempted to overuse try-catch-log (for example, on the Send() function) and debug-print statements, but here are some things I can see that could cause a crash or other unexpected failure:
There is no guarantee that "ifs" is instantiated before use. If you for some reason skip the file-length step, the file step will crash with a null pointer exception.
The entire send function is hugely thread-unsafe. For example, if a second request arrives before you're done servicing the first one (which is entirely possible due to where the event gets signaled) then the values of "ifs" and "CurrentStreamPosition" and so on will be unpredictable at any given time. Since CurrentStreamPosition seems to be monotonically increasing, that's probably not going to cause an out-of-bounds exception, but it could cause you to enter a state where the test "if (CurrentStreamPosition < ifs.Length)" always fails.
The line "data = "TransfersComplete<EOF>";" never does anything; the next line (immediately following it) overwrites that variable. If you cared about that string, too bad.
FileIndex never changes; I hope you're only ever sending one file here...
You don't actually check that the number of bytes sent is the number you meant to send (admittedly, it *should* be, but there are cases where it won't be).
The last 150-byte chunk of every file transfer is truncated to the first byte. This is because "CurrentArraySize" is reset to 0 on every iteration of the byte-read loop (why use a byte-read loop?) so whenever "CurrentStreamPosition < ifs.Length" tests false, the "filedata" array will be resized to one byte (or zero if the file is an exact multiple of 150 bytes, which presumeably be correct).
There are probably more, but that's what jumped out at me (well, and some technically correct stylistic issues, like the "... == false" test). Given that your protocol seems to rely on end-of-message flags, I'm guessing that your problem is that since the last part of the file is almost always truncated, that marker is never getting sent. This probably leads to the client concluding that the server will be sending it more data, which it does by sending another "file" request. The server attempts to respond and immedately hits the CurrentStreamPosition < ifs.Length check, fails, goes to the else case, and tries to send a 1-byte packet containing a NULL byte.
Incidentally, does your file transfer protocol really require that the client request each 150-byte chunk one at a time, using a new TCP connection each time? That's... awfully inefficient.
Click to expand...
Click to collapse
I know it is inefficient, but I'm rather new to sockets. I just want it to get working in a "beta stage" then ill optimize it (hance the FileIndex never increasing, the blatant lack of try-catch blocks).
On the client side, once the bytes in the buffer are processed, the server gets another send that to send the following 150 bytes (i use 150 just for the lulz).
So basically, the workfow is as follows:
ask metadata length >server gives the length >client adjusts buffer>ask metadata
ask metdata >server gives metdata>client processes the data>asks file length
ask file length>server gives file length>client adjusts a huge array of bytes in which the file will reside (i know this is horribly inefficient, but at some point i will write directly to a file stream)>asks for the first 150 bytes in the file.
server gets the request, sends 150 bytes to client>client copies the 150 bytes in the array created earlier, the asks for the next 150.
I am using 150 just to make sure the data never splits in more than one buffer.
When the file transfer occurs, a different message is used to signal the end of transfer. Client side counts the bytes it gets, and when it is equal to the file length, it no longer asks 150 bytes.
The whole thing seems to be safe from crashing until it gets to the part where it sends the file. I am aware that in the code i gave you there's some file streams not getting closed, but i've fixed that and the problem still occurs.
Since The debugger won't help me at all, I decided to use a WCF service instead.
mcosmin222 said:
What do you mean by socket multthreading code? You mean the use of async methods? or having the thread work on background, using the socket?
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I mean worker threads not async.You will always have to have a thread in the background to "accept". once you accept you "read" in a new thread and the parent thread "accepts" again. Accept will freeze the thread.
On the other side, you simply "connect" and "write" in the same thread.
Read and Write is done in a loop via pre-defined buffers syncronously.
But if you want the server to give a response, the above flow is the other way around, and it is then when things get complicated. (server needs to "connect" and client needs to "accept" over a different set of ports and different threads)
Probably if you want to have reliable connection you will need the server to come back with a response "give me more" or sth.
So, trying to assist, it was my guess that drops or stalls could be because the above flow is not implemented properly.
Edit Oh ho, missed a whole new page so I am sorry if the reply is irrelevant now.
I would suggest you use the sync methods of sockets and not callbacks because is super easier to debug. ThreadPool.QueueSth (ctr + space I dont remember how it's called is your friend to handle threads yourself.
And try to separate pure socket handling from domain handling (lengths, metadata, etc). Send some bytes back and forth, clean-up and then move to domain specific things!
Moving the line that resets CurrentArraySize to outside of the for loop may well sove your problem. I'd try that first.
Optimization involves, among other things, removing try blocks. Unoptimized code, when you're trying to just make thigns work, ought to be full of them.
Don't forget that exceptions will not bubble up the call stack across threads. In addition to threads you create yourself, any async callback will happen on a different thread than the one that called the async function. If an uncaught exception occurs, the thread will die. If enough threads die, the program may crash (or at least hang) due to threadpool exhaustion.
GoodDayToDie said:
Moving the line that resets CurrentArraySize to outside of the for loop may well sove your problem. I'd try that first.
Optimization involves, among other things, removing try blocks. Unoptimized code, when you're trying to just make thigns work, ought to be full of them.
Don't forget that exceptions will not bubble up the call stack across threads. In addition to threads you create yourself, any async callback will happen on a different thread than the one that called the async function. If an uncaught exception occurs, the thread will die. If enough threads die, the program may crash (or at least hang) due to threadpool exhaustion.
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I avoid try-catch in unoptimized code to see where actual exceptions occur (sometime the debugger doesn't break on exception).
Nop still not working.
The thread still appears to be crashing, even wrapped with try catch.
Do you at least know *which* function it's crashing in? Try putting a breakpoint on each function header and then, when one of them is hit, step through the execution until the thread dies. Work backward from there to find the problem.
GoodDayToDie said:
Do you at least know *which* function it's crashing in? Try putting a breakpoint on each function header and then, when one of them is hit, step through the execution until the thread dies. Work backward from there to find the problem.
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The send function (the one with the case switch) appears to be crashing.
It executes the function then enters the listening stage (does not execute the callback).

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