[Q] SOAP Call - Java for Android App Development

[Q] SOAP Call - Java for Android App Development

Hello all... first time post in this area. Hope Im in the correct spot. I am trying to make a small app that will connect to a webservice. Typically we pass up a JSON object in C# to get a JSON return from our webservice.
Being new to Java, I am struggling with this. Any help would be much appreciated.
assume the following:
http://mysite/webservice.asmx
sO = "{"s_O":{"arPR":[{"sPSUniqueID":"K001"},{"sPSUniqueID":"K002"}]}}";
sUser = "mName";
sPassKey = "aqyu08ioa";
sMethodName = "mGetSummary";
our normal call in c# would look something like this...
JSONString = return androidSOAPCALL( methodName, sUser, sPassKey, sO);
Thanks for help on this guys...
Vic

You could do it that way: http://www.vogella.com/articles/AndroidJSON/article.html
However, you could also use a library made by Google which is calles Gson: http://code.google.com/p/google-gson/
It is much easier with the library.
A tutorial on this (points 3 and 4): http://www.mkyong.com/java/how-do-convert-java-object-to-from-json-format-gson-api/

nikwen said:
You could do it that way: http://www.vogella.com/articles/AndroidJSON/article.html
However, you could also use a library made by Google which is calles Gson: http://code.google.com/p/google-gson/
It is much easier with the library.
A tutorial on this (points 3 and 4): http://www.mkyong.com/java/how-do-convert-java-object-to-from-json-format-gson-api/
Click to expand...
Click to collapse
Those are excellent articles on JSON. Thanks for the reference. I will most likely be using that to handle the returned JSON object.
However, my question is more concerning making my SOAP call to the asmx webservice. I cannot seem to relate any samples to my particular case as mentioned above.

Related

simple XML DOM parser example?????

can anyone here know how to make it work with a local xml file? been stuck for weeks.
thanks

DOM or Sax
kadmos said:
can anyone here know how to make it work with a local xml file? been stuck for weeks.
Click to expand...
Click to collapse
I'm new to Android dev but the only examples I've come across of xml processing is using the XmlResourceParser, which uses a Sax-like technique rather than walking an in-memory dom.
The books Pro Android 2 and Beginning Android 2 have decent examples.
Sorry, I tried to post links above but was not allowed to because I'm new here ...

Here's a DOM example ...
rmhand said:
I'm new to Android dev but the only examples I've come across of xml processing is using the XmlResourceParser, which uses a Sax-like technique rather than walking an in-memory dom.
Click to expand...
Click to collapse
Ha! Well, since posting that less than an hour ago I've discovered that you can in fact create a Document Object Model from an XML file. The Beginning Android 2 book has an example that looks something like this:
Code:
InputStream in = getResources().openRawResource(R.raw.myXmlFile);
DocumentBuilder builder = DocumentBuilderFactory
.newInstance().newDocumentBuilder();
Document doc = builder.parse(in, null);
NodeList animals = doc.getElementsByTagName("animal");
for (int i=0;i<animals.getLength();i++) {
items.add(((Element)animals.item(i)).getAttribute("species"));
}
in.close();

IBM has a very good example of all xml parsers available for Android:
http://www.ibm.com/developerworks/opensource/library/x-android/index.html

help with my time organizer app

I'm developing an organizer app as my bc. thesis and I don't have any real Android developer to consult, so I made this thread and hope somebody will help me and point me in the right direction.
I just started to work on it and I have roughly 1 month to make something useable out of it.
So... the first thing that comes to my mind right now is synchronization.
1. I don't know if I should implement it or not.
I have a hosting with 1.5 GB space, a relatively fast connection. Would syncing data (text (probably xml) only) with this server slow it down significantly ? How many users could an average server take ?
And another one regarding sync:
2. I'd like my application to exchange data with my server under the google account on which the device is logged in, so no registration will be neccessary (I suppose the majority of devices are loggen in with google). I'll probably need to get the user's google account name on every sync session. Is that possible ?
The app will already have a server-side app to edit your events and stuff, so I'll need the user's login information again to retrieve his data from my database, but I won't have his password, so I can't make a usual login form. I guess Google has some API to figure out if a user is logged in, doesn't it ?
Any advice will be appreciated.

Can I open a menu with a simple button click ? Like a context menu but for short clicks.
// I solved the **** outta this one.
Still waiting for answers on the first post.

"Organizer App" really doesn't tell us what you're trying to do. It's hard to answer questions if one doesn't know that basic plan of the project you're trying to create.

Check this -> Basic info about my bc thesis

Nice web page...ambitious project for a 4 week time frame.
As a programmer, you know to start small and add functionality as your program grows.
I would start by making a simple"To Do" list: Add item, Delete item, Edit item, Mark item done, Save this list, Recall a list, Delete a list.
Post back when that's done

Rootstonian said:
Nice web page...ambitious project for a 4 week time frame.
As a programmer, you know to start small and add functionality as your program grows.
I would start by making a simple"To Do" list: Add item, Delete item, Edit item, Mark item done, Save this list, Recall a list, Delete a list.
Post back when that's done
Click to expand...
Click to collapse
Agreed 100%.
@ OP:
I don't know much about syncing, but it won't have a large cost of the server's resources - syncing an CSV or XML file is pretty trivial. Even if you have a low bandwidth cap, text files are quite small. So you should be fine in terms of that.
Nobody can give you a "set number" - ie. the server can take "X people." It greatly depends on the server type, how much bandwidth is allocated to you, your traffic priority, etc. I mean if it's one server with like a xeon processor then it can probably handled a pretty heavy load (say 50 probably? (and yes, I'm kind of pulling that number out of my ass)). Though most web hosts don't just dedicate one server to each customer. Typically, now-a-days, everything is virtualized. Everything is unified using server farms (ie. multiple servers or computers) virtually, then virtual chunks of resources are distributed to clients. So even if somebody could give you exact numbers (which is impossible), they'd most likely be wrong. That is unless you paid extra to have a particular server or particular number of servers dedicated to you...but even then, there's a high chance that it's just a chunk of a virtual server farm.
He's right, this is pretty ambitious in a 4 week period, especially if you have other activities going on as well. It's even more ambitious if this is your first app. You may want to reconsider your objectives given your time frame.
As for the google login, you'd need to look at the google API, and see if there's a way to verify peoples' usernames and passwords. If you can, then it's just a matter of encrypting them and storing them in a properties file or something.
Hope that helps ya out some.

Rootstonian said:
Nice web page
Click to expand...
Click to collapse
Thank you
I know, I know. I could have started 4 months ago. But I didn't, the lazy bastard I am.
This is the practical part of my bc thesis. The ultimate deadline is 3rd of june, but I have to have my theoretical part (30-50 pages of text, if IIRC) done by then, all printed out and ****. So I plan to work as hard as I can on this till the end of this month and then start to work on both at the same time. I really don't have any other duties in school, since I have a nice reserve of credits so this is my priority #1.
The main objective is geo-tasks, since that's what the name of my thesis says. Everything else is just an addition (i.e. the widget, that was just an idea, I doubt I will have time for that). So I'd rather start with that (I know, It's the hardest part). Or do you still think I should start with the to-do's ?
You can check out my last night's post to see what I've been up to the last 2 days and what I'll be up to next.

What is your level of Android programming experience (None, Basic, Intermediate, Advanced)?
And I'm a little fuzzy on the whole "Geo" thing. Is it like I have a list "Get milk, bread eggs", "Pick-up dry cleaning", "Get oil change" and then your app is going to "sense" when I'm by the grocery, dry cleaner's and oil change place? Which grocery? I use 4 different stores. Same dry cleaner and oil change though usually.
If so, you are going to need to code in lat/long coordinates for these places and then compute your location vs one of the merchants, compare that merchant to an "active" TO DO list item and pop-up an alert of some sort if you're within a mile. Wow
Your project, you know your skill level. Start where you want I guess LOL.

I think it's more of an agenda type thing - that syncs.

@Rootstonian
I'd say basic, but quickly crawling up to intermediate.
It's almost like you said, but there's only one location for every task. Maybe in a later version...

Well, good luck. Keep us posted

Will do. Hope you guys will keep on helping me

I need to use my database object in more than one activity. How do I pass it from one activity to another ?
Should I create a new instance in each activity ? Or should I create a content provider ? (I'd rather not - they're quite complicated for me and I only need to access the DB in this app).

I'm going to assume you are using a database helper type class.
No need to pass data from Activity to Activity; just open, use and close the database in each Activity as required.

I have a problem.
I created a LinearLayout for all the tasks in the database. Now I want to register all of them for a context menu. I can do that, but I can't figure out which one's menu was triggered.
LinearLayout has a setId method, but it only takes integer values, which is no good for me, because I have 3 types of tasks and if I assign them their id from the database, then the same ID will probably be assigned to 3 different views.
I could use some sort of multiplication, like for timed tasks I would multiply the ID by 10 000, but that's not elegant at all, and it would crash after a few months of using the app.
So what do I do now ?

I'll paste some code.
Code:
public void drawTasks() {
TextView emptyText = (TextView) findViewById(R.id.empty_todo);
if (tasks.isEmpty()) {
emptyText.setVisibility(View.VISIBLE);
} else {
emptyText.setVisibility(View.GONE);
Iterator<Task> it = tasks.iterator();
//create views
while (it.hasNext()) {
//create a temporary object
Task tmpTask = it.next();
//get it's properties
long id = tmpTask.getId();
String title = tmpTask.getTitle();
String description = tmpTask.getDescription();
int important = tmpTask.getImportant();
int finished = tmpTask.getFinished();
//create new LinearLayout for this task
LinearLayout newTaskLayout = new LinearLayout(this);
newTaskLayout.setId((int)id);
newTaskLayout.setOrientation(LinearLayout.VERTICAL);
newTaskLayout.setPadding(5, 0, 0, 10);
taskLayouts.add(newTaskLayout);
//create new views for these properties :
//title
TextView newTaskTitle = new TextView(this);
newTaskTitle.setText(title);
newTaskTitle.setTypeface(null, Typeface.BOLD);
//important tasks are highlighted
if (important == 1)
newTaskTitle.setTextColor(Color.RED);
//finished tasks are italic
if (finished == 1)
newTaskTitle.setTypeface(null, Typeface.ITALIC);
//description
TextView newTaskDescription = new TextView(this);
newTaskDescription.setText(description);
if (finished == 1)
newTaskDescription.setTypeface(null, Typeface.ITALIC);
//add views to this tasks' LinearLayout
newTaskLayout.addView(newTaskTitle);
newTaskLayout.addView(newTaskDescription);
//add new linearLayout to tasksRootLayout
tasksRootLayout.addView(newTaskLayout);
}
}
}
This is self-explanatory. taskLayouts is an ArrayList of LinearLayouts where I keep the pointers to all layouts that need to have a context menu.
There are 2 other similar methods: drawTimedTasks() and drawGeoTasks() which do basically the same (I couldn't figure out a way to do it with one universal function).
Here's how I register them for context menu:
Code:
private void registerViewsForContextMenu() {
//register control bar buttons
registerForContextMenu(newGeoTaskButton);
registerForContextMenu(newTaskButton);
Iterator<LinearLayout> it = taskLayouts.iterator();
while (it.hasNext()) {
registerForContextMenu(it.next());
}
}
And here's how I'm checking for context menu trigger:
Code:
public boolean onContextItemSelected(MenuItem item) {
switch (item.getItemId()) {
case ...
return true;
}
...
}
return false;
}
What am I doing wrong ?

Anyone ?
----

I haven't really been following this thread so I don't know all the details of your app, but I'll try to help.
So each task has 3 views for it? Each task is in the db once? I'm a little foggy on how you're storing them and what the correlations are between views, events, and types of event, more specifically the latter.
If you explain that a little more clear, I can try to help a little better.

There are 3 types of tasks : simple, timed, and geo tasks. Each type has its own table in the db, hence it's own IDs. That means, the first geo task, first simple task, and the first timed task ever added have all the same ID = 1. That means if I want to give their views unique IDs, I can't use their IDs from the database.
So I'm trying to figure out a way how to give the view ID's so I can find out which database record they represent.
In an ideal world, I would be able to define a string ID (i.e. geo_1, simple_1, timed_1), but this is not the case. I dunno why... in XML you give your views string IDs, but programatically you can't.

grandioso said:
There are 3 types of tasks : simple, timed, and geo tasks. Each type has its own table in the db, hence it's own IDs. That means, the first geo task, first simple task, and the first timed task ever added have all the same ID = 1. That means if I want to give their views unique IDs, I can't use their IDs from the database.
So I'm trying to figure out a way how to give the view ID's so I can find out which database record they represent.
In an ideal world, I would be able to define a string ID (i.e. geo_1, simple_1, timed_1), but this is not the case. I dunno why... in XML you give your views string IDs, but programatically you can't.
Click to expand...
Click to collapse
If all of the tasks have common elements (even if they don't really), you can merge them into one table. Then define an enum or something for the task type, as a simple field in the table. This removes the issue with duplicate ID's, while still being able to differentiate what type they are. You can typically leave fields blank in a database, so you wouldn't have to worry about what's filled in for tasks that don't have particular fields associated with them, just verify all fields prior to mutating the database.
If you're hellbent on keeping three separate tables you can hold a global ID, which can be an intersection between all three tables. So this wouldn't be the primary key, just a global ID, and you can key them up by that. Not entirely sure where you'd keep it to persist over power cycles unless you just make a 4th table with one row and store it in there. Or just throw it in the program's data somewhere.
The reason you can define things in the XML is he XML is compiled into the R class at compile time...though everything in there *should* have a corresponding methodology to get it done programatically. Though if you're talking about the primary key, as far as I know that is always numerical. So the ideal world may not apply - BUT, that doesn't mean you can't create a field that stores a string id (which I wouldn't, because string comparisons take a lot of time, but whatevs).
Hope that helps you out some, I don't really touch databases and am very new to Android programming, just know what I know from absorbing info from others - but I know a pretty decent amount about programming in general and know Java pretty well so I can probably help you out the best I can in some respects.

newbie project.

Hi I want to make an app that loads a web page and auto refreshes.
Also I would like it to open any links and search for any text the user has asked to see. (I.e. the name of a secific town) And if found to either highlight that link on the displayed web page or open tabs for any instance.
It sounds simple but I have no idea where to start or what language to code in (although I was thinking java script).
Found a bunch of simple free web apps but would like to do it from scratch.
Any help would be great
Sent from my GT-N7100

The app needs to be written in Java.
However, you can load a html page into a WebView and do the actual coding in the web page you display. That enables to do the simplest things in JavaScript.
If you want, send me your html file and I will create an app for you which displays this page.
But it will be a better learning experience if you do it yourself.

Thanks for the reply but the web page I have in mind is a news page for the fire service I work for.
It has links to incidents with more details. I wanted to load the page and search each of the links for my stations.
That way my wife only has to check her phone to see where I am.
I would love to do it all myself. Have some experience in vb but im not sure if you can program in that for android.
Plus I really want to learn java lol and I learn better by doing. If you can give me some pointers I would be very happy
Sent from my GT-N7100

jaffa1980 said:
Thanks for the reply but the web page I have in mind is a news page for the fire service I work for.
It has links to incidents with more details. I wanted to load the page and search each of the links for my stations.
That way my wife only has to check her phone to see where I am.
I would love to do it all myself. Have some experience in vb but im not sure if you can program in that for android.
Plus I really want to learn java lol and I learn better by doing. If you can give me some pointers I would be very happy
Sent from my GT-N7100
Click to expand...
Click to collapse
Look at the methods of WebView.

The text it searches for, is it all on that one html page? Can it find the identifying info in the URL of each link or will it need to actually load each linked page and search for the text in those?
Sent from my SAMSUNG-SGH-I727 using xda app-developers app

It would need to open each link in order to search I think.
Although it doesnt need to be made visible unless it matches the search criteria... I know that with the vb I could open a link in a new page but keep its visibility zero while it is manipulated... is that possible in java script?
Sent from my GT-N7100

jaffa1980 said:
It would need to open each link in order to search I think.
Although it doesnt need to be made visible unless it matches the search criteria... I know that with the vb I could open a link in a new page but keep its visibility zero while it is manipulated... is that possible in java script?
Sent from my GT-N7100
Click to expand...
Click to collapse
That makes it a bit harder. I don't know javascript very well but either way, I would do it using the Java WebView class to load the links. I have written an app once that used the JSoup library to download and parse the needed needed info from links, assemble them into a small summary page and displayed with WebView. I don't know if thats the best way but it worked for me...

You could search the html file for "<a href".

You basically want a web crawler^^
Regular expressions would be the right place to look, +1 for @nikwen 's answer.
I would basically do something like an edit text where the user inputs the words he wants to find on the webpage, and use regex to parse all <a href / </a> tags in a given html page which the app would previously have downloaded.
You could do something like this to parse the links (this will give you everything between ) :
Code:
File file = new File("/sdcard/index.html");
if(file.exists()) {
StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
while ((line = br.readLine()) != null) {
if (line.contains("<a href")
line.replaceAll("(<a href=\")(.+)(\")(>.*</a>)", "$1$3$4");
text.append(line);
text.append('\n');
//the text variable will contain all the links on your page by the end of the loop
}
}
catch (IOException e) {
}
You could then assign the text variable to a TextView which would have the android:autoLink="web" flag, thus displaying all links to the user

Thanks very much for your input, although i'm extremely new to java so its taking some time to get my head around the whole thing lol.
I have recently found Basic4Android which is very similar to Visual Basic. I have managed to pick that up a bit quicker than Java.
I was wondering if it is a popular language on here and if there are many people i may be able to ask specific questions re my app?
I have managed to "map out" what i want and even start the programming having designed several pages.
The thing i wondered about this is...
Once a web page is loaded are you able to programatically (is that a word?? ha ha) open links found on that web page (for me to search for a station).
the search string I am using, the user selects from a Spinner (drop down box) that i have populated.
once i have the links that have the mentioned stations i can use a tab view to have the main page and all incidents open together.

jaffa1980 said:
Thanks very much for your input, although i'm extremely new to java so its taking some time to get my head around the whole thing lol.
I have recently found Basic4Android which is very similar to Visual Basic. I have managed to pick that up a bit quicker than Java.
I was wondering if it is a popular language on here and if there are many people i may be able to ask specific questions re my app?
I have managed to "map out" what i want and even start the programming having designed several pages.
The thing i wondered about this is...
Once a web page is loaded are you able to programatically (is that a word?? ha ha) open links found on that web page (for me to search for a station).
the search string I am using, the user selects from a Spinner (drop down box) that i have populated.
once i have the links that have the mentioned stations i can use a tab view to have the main page and all incidents open together.
Click to expand...
Click to collapse
Since Java and C++ are the native languages for Android apps, there will not be that much devs which can help you.
Learn Java. It is a great language.
---------- Post added at 01:23 PM ---------- Previous post was at 01:22 PM ----------
And to open links programmatically: There is a method in WebView to load a page. Just load the new one.

If you're using a webview then any familiarity with JavaScript will help. You can find and download all the links on a page using Ajax, quite easily. For example, if you included the jQuery library in your page then you could do the following...
HTML:
$("a").each(function() {
$.ajax({
url: $(this).attr("href");
success: function(data) {
// do something with "data" here - it's a linked page
}
});
});
But, if you're familiar with basic then B4A may be the way for you to go. You'll need to learn how to inspect the DOM (document object model) which is the code behind a webpage.
Also, Stack Overflow is invaluable for quick help from experienced developers. A combination of this place and that (http://stackoverflow.com/questions/tagged/basic4android) will certainly get you going in the right direction. Just a word of warning.... If you're going to post on Stack Overflow then don't just ask "how do I do this?" It doesn't go down well. Show them what you have done and tell them what you want to achieve. They like people who try for themselves first
Good luck.

You definitely need Jsoup here! It is a very fast and easy to use (java) library.
Take a look at this code:
Code:
String URL = "yoururl";
String linkText;
String location;
Boolean stationFound;
ArrayList<String> locations = new ArrayList<String>();
// Get all links to incidents
Document doc = Jsoup.connect(URL).get();
// You have to take a look at the HTML and get some unique attribute to get all the incidents
// This can be a class/id/div etc.
Elements IncidentLinks = doc.select("a[class=someClassToSelectIncidents]");
// Now loop through all incident links
for(IncidentLinks : link){
[INDENT]
// Get the URL of the current detailed page
URL = link.attr("href");
// This is the more detailed page
doc = Jsoup.connect(URL).get();
// Get the HTML of the detailed page
String pagecontent = doc.toString();
// If your station is named in this HTML add it to the locations array
if(pagecontent.contains("Yourstation")){
[INDENT]
// Get the current location
// You need to find it yourself, take a look at the HTML
// It could be something like:
location = doc.select("div[class=location]").text();
// Add the location to the array
locations.add(location);[/INDENT]
}
[/INDENT]
}
// Now you have an array with all locations where your station is at the moment
// I dont know if your station can be at multiple locations at once
// You could loop through them and add them to a textview.

Thanks for all your advice i am starting to learn java, i have got eclipse and am watching all the video lessons i can grab lol i have a couple of books and a complete reference book 8...
I was wondering if i needed to reference this jsoup library before i can use it in eclipse.
Please be patient with me lol i have 2 jobs 3 kids and a prego wife so can be.... well, skatty is a polite way of putting it!

You just have to load the library into your project, it's very easy, just google it. If you have some programming experience you'll learn jav pretty fast. Good luck!
Sent from my NexusHD2 using xda app-developers app

jaffa1980 said:
Thanks for all your advice i am starting to learn java, i have got eclipse and am watching all the video lessons i can grab lol i have a couple of books and a complete reference book 8...
I was wondering if i needed to reference this jsoup library before i can use it in eclipse.
Please be patient with me lol i have 2 jobs 3 kids and a prego wife so can be.... well, skatty is a polite way of putting it!
Click to expand...
Click to collapse
Copy it into the libs folder of the project and it will be linked automatically.

Hi,
Still studying away i was wondering if there is a resource webpage i can download other projects to open in eclipse so that i can explore all the bits I'm reading about.
When i did VB i would often look at other projects with similar components as mine so i could get an idea on how to implement things properly.
I am getting the hang of the eclipse environment but there is so much more to the project area (resource files, xml and java etc).
Does anyone have any recommended sites for tutorials books for reading etc?
Cheers guys

jaffa1980 said:
Hi,
Still studying away i was wondering if there is a resource webpage i can download other projects to open in eclipse so that i can explore all the bits I'm reading about.
When i did VB i would often look at other projects with similar components as mine so i could get an idea on how to implement things properly.
I am getting the hang of the eclipse environment but there is so much more to the project area (resource files, xml and java etc).
Does anyone have any recommended sites for tutorials books for reading etc?
Cheers guys
Click to expand...
Click to collapse
I'm obviously assuming you have the Android SDK installed, so just look in there for the samples folder. It's full of demo apps to rip apart and see how they were made

ok im right fed up!!
i havent had time to be able to read or study or anything!!
would someone throw me a bone and upload a template based on the description i gave earlier... i know its freakin lazy but im having a **** ol time of it recently (health issues... hospital time etc) and could really do with the help...
the url of the newsdesk is
http://www.dsfire.gov.uk/News/Newsdesk/IncidentsPast7days.cfm?siteCategoryId=3&T1ID=26&T2ID=35
and as i said just the option of either viewing the page directly or if selected a station from a drop down box the main url shown on the first tab with other tabs populated by incidents with the selected station preferably from todays incidents. (see link)
i would consider this to be my luck turning and could really do with it
thanks

jaffa1980 said:
ok im right fed up!!
i havent had time to be able to read or study or anything!!
would someone throw me a bone and upload a template based on the description i gave earlier... i know its freakin lazy but im having a **** ol time of it recently (health issues... hospital time etc) and could really do with the help...
the url of the newsdesk is
http://www.dsfire.gov.uk/News/Newsdesk/IncidentsPast7days.cfm?siteCategoryId=3&T1ID=26&T2ID=35
and as i said just the option of either viewing the page directly or if selected a station from a drop down box the main url shown on the first tab with other tabs populated by incidents with the selected station preferably from todays incidents. (see link)
i would consider this to be my luck turning and could really do with it
thanks
Click to expand...
Click to collapse
Thanks for the link, now its more clear what you want.
At first take a look at the HTML of the webpage.
All incidents are listed per day as you can see in this image. The incidents are wrapped inside a DIV tag:
{
"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"
}
When we take a closer look, the link of an incident is stored in this TD tag.
So now we know the structure of the webpage we need to itterate through all the TD tags with the links in it.
If you look even closer you can see all the TD tags are inside a TABLE tag (ORLY??), BUT with the same class: class="tabularData".
The path to each page looks like this TABLE(class="tabularData") > TR > TD(first) > A
When you've got all the links you can visit the page and extract the word(s) you are looking for.
You can do this in two ways:
Use PHP/javascript/whatever to create your own website which displays the data. Then use WebView to display it in your own app.
Use Java to find the data and show it in an android layout (listview).
In PHP you want to use XPATH (http://stackoverflow.com/search?q=xpath)
In Java you want to use JSOUP (http://stackoverflow.com/search?q=JSOUP)
In Android it looks something like this:
HTML:
// Get the content of page
Document doc = Jsoup.connect("http://www.dsfire.gov.uk/News/Newsdesk/IncidentsPast7days.cfm?siteCategoryId=3&T1ID=26&T2ID=35").get();
// Select each day, this TABLE tag is inside the DIV tag you see in the first image.
Elements days = doc.select("table[class=tabularData]");
// Loop through each day
for(Element day : days){
// Select each incident
Elements incidents = day.select("tr");
// This loops through all URL's of the incidents.
for(Element incident : incidents){
// And get the url of the page to get more details of the incident
String url = incident.select("td").first().select("a")..attr("abs:href");
// Now get the content of the detailed page
String incidentpage = Jsoup.connect(url).get().toString();
// And check wether the page contains the string you are looking for
If(incidentpage.contains("Stringyouarelookingfor"){
// Do something
}
}
}
This is just a very rough piece of code, and it might not (probably doesn't) work. But I hope you get the idea and can go on by yourself.

[GUIDE] Best Practices for Android Java

During recent development of my app (see my signature) I focused a lot on how to optimize the already working code further in order to make it smoother without loosing quality or using too much memory. Well I came across some mistakes I had made in my early days of developing Android so I figured it might help the beginners and intermediate developers. So here I collected my suggestion of common mistakes and best practices in Android. Let me start by making you familiar with a motto which you might know if you have developed Perl before.
TIMTOWTDI
There's more than one way to do it, in short TIMTOWTDI is a well known aspect of the Perl language, which aims at giving programmers the freedom to choose their way of doing things. It “doesn't try to tell the programmer how to program.” Well it does have various disadvantages such as possibly messy code and barely readable code, but it offers programmers to use their preferred style.
The only reason why I'm bringing this up here is because it helped me a lot to think that way, since TIMTOWTDI sometimes applies to Java as well and a way somebody else is preferring might not be better than your own way. But it is never bad to have a look at how others code the important tasks and sometimes the performance or readability gain is tremendous. So I'm not telling you to exactly use my way, but advice all beginners to perhaps rethink their code .
Tweaking Android Apps
The first step is always to look at what the awesome Android documentation says about performance, so I can more than advise you to read this straightforward article about what to do and not to do on Android. It covers some very important performance issues like the expensive object creation and method invocations. It is crucial to follow those basic rules while trying to develop fast Android apps. I will cover and further explain some of their suggestions here, but will try to also look at them from a developer's perspective who cares about readability and simplicity.
Now onto the code, let's start with some basic Java practices and then move on to some more Android specific styles and improvements.
Looping wisely
Often it doesn't matter if you write slow code and lose 1 or 2 milliseconds but especially in loops and everything that can be called once a frame you suddenly loose a lot of time. Thus it is crucial to especially pay attention to those repeated parts of your code like the onDraw() method in your custom view implementation (see last section) and start optimizing there. Let's take a look at what kinds of loops we have, the slowest first and the fastest ones towards the end:
while
The while loop is probably the first complex programming structure you learned, and just writing
Java:
success = false;
while (!success) {
trySomething();
}
is extremly readable but can potentially run forever or longer than you need it to. One aspect which is often overlooked is that the condition inside the parentheses will be checked on every run of the loop! So even a simple string.length() call can be optimized (if the String won't change) saving its length as an int and then using that in the condition block.
Its unpredictability and lack of possible tweaking done by the JIT makes the while loop a tool that needs caution but is sometimes crucial to complete the task. Just make sure you only use the while loop if there is no way to predict when your condition is false. For almost all other cases, you can do some calculations and use one of the iteration loops:
for (traditional)
This one is widely used like this:
Java:
for (int i=0; i<getSize(); i++) {
doSomethingWithIndex(i);
}
Even though this is more predictable, consider how the program will run: Before every execution of the block, the condition i<getSize() has to be checked, so getSize() is called (and an Android, method calls are expensive!). You could now think, alright, we'll just cache our size upfront like we did with in our while loop, but examine the following fast example of iterating through an array:
Java:
for (int i=getSize()-1; i>=0; i--) {
array[i] = getNewValue(i);
}
The trick is starting at the last value and then iterating backwards until 0 is reached. This may not work at all times, where the order of the blocks may be important or it is redundant due to having a fixed end value, but it saves both method calls and memory usage needed to get the last value before going into the loop.
But that is hardly readable and you often have to rethink because of looping backwards, so we can do better can't we?
for (iterator-based: “foreach”)
Dealing with an array, List or other collection of data you can easily do something for every part in that collection using the foreach loop:
Java:
for (Object item : objects) {
doSomething(item);
}
That is the fastest way you can iterate through any kind of iterable collection because it can be heavily optimized by the compiler and is also simplistic and readable. The only problem here is that you don't have the index of the item you're getting and you can't write data to the collection. To accomplish that one of the slower for loops must be used.
Keywords do matter
This is a minor one that is overlooked often. Beginners in Java mostly don't use keywords and access modifiers like “private”, “public”, or “final”. That is fine since we all love simplistic code don't we? And an honest word, if you don't write a library or work on your code with a big team, you don't have to know much about the access modifiers, but if you want to, there is always the Java documentation. But the “final” identifier is actually pretty important to both the ones reading the code and also the compiler, since it can just insert its value into the references. That means, that whenever you declare an instance variable, think about if it is likely to change or if you can declare it as final. Within methods, making use of the “final” keyword does not really change much for the compiler, but it sometimes helps you make a clearer design so you directly get a compiler warning whenever you're trying to change a final variable's value.
A side note on making “static” variables and fields – I wouldn't recommend that on Android unless you know what you're doing or you're using it together with “final”. A “static final” instance variable is the best way to declare constants in Android because the compiler can replace it fast and ART can replace it during the install of your app!
Strings are special
Let's talk about something that is fundamental to Java – the String object. Well it's not a real object since it is actually immutable. That means a String can only be created or collected by the garbage collector, it can't be changed (which is very important since object creation is god damn expensive in Android so it would make our apps pretty slow)! Wait, then what happens if I call one of the awesome methods in the String class like substring() or replace()? And here comes the downside: These methods have to create new Strings and the old one is collected by the garbage collector. While this might be totally alright if you're just parsing some basic user input, if you need to perform some heavy String operations like many substrings, a whole lot of unused garbage and overhead is created. This doesn't only mean that you are temporarily using a lot of memory, with the garbage collector needed to kick in it also affects your performance.
So how do we get around this problem? Luckily there is a Java class which can do almost the same as the default String implementation, the StringBuilder. This class will hold a char array with all the chars you had in your String. The class can take care of managing that array like initializing it with a default length of 16 and creating a larger array once you have more characters that would fit into it. Take a look at the constructors as well – with new StringBuilder(length) you can directly make that array as long as it needs to be and with new StringBuilder(string) the array is instantly filled with the string. The big advantage the StringBuilder is that it can modify the array instead of having to create new Strings every time. If you're finished with the heavy modifying, just call toString() to get the String back.
If you want to read more about it, here's a nice article.
Android-specific tips
Bundling is better than trundling
Let me explain this with an example: Let's say you are dealing with some data concerning persons so you are saving their name, age and gender. In any object oriented language like Java you would create a wrapper object holding that data:
Java:
public class Person {
private String name;
private int age;
private boolean isMale;
public Person (String name, int age, boolean isMale) {
this.name = name;
this.age = age;
this.isMale = isMale;
}
// additional getters and setters go here.
}
Of course you could do that in Android as well, but you will encounter this problem: What if you need to save your Person array or need to pass a specific Person to another activity? Well, you have a few options available:
You could override the toString() method in Person so it contains all its data and parse your array into a String array manually. Then another constructor will be needed to get the data back from the String using our beloved String operations. But there is still the problem that when you want to add data to the person like height later, you have to reconsider the toString() method and it's constructor counterpart.
Alternatively, wanting to integrate it better into the system, you might want to implement Parcelable in the Person class. That way you can directly put person extras to your Intent or save it to SharedPreferences. But that seems like more work if you want only a simple container for your data. Once you need have a more complex class it might be advisable to make it Parcelable (perhaps using the Android Studio plugin, thanks @nikwen), but let's start with an easier apporach here.
This is how I do it: I use a Bundle instead of a person class to store all the needed data. The Bundle class already implements Parcelable and and simplifies adding data for you. What is more, you are probably already familiar with it since you get one calling getExtras() on the starting Intent of your activity! Now back to the example, this is how it would be done:
To not get confused about all the keys you need, let's create a class containing some static final keys:
Java:
public class Person {
public static final String NAME = “person_name”; // will contain a String
public static final String AGE = “person_age”; // will contain an int
public static final String ISMALE = “person_ismale”; // will contain a boolean
}
While this is only needed for consistent keys, here is how you would create the Person:
Java:
public Bundle getPerson(String name, int age, boolean isMale) {
Bundle person = new Bundle();
person.putString(Person.NAME, name);
person.putInt(Person.AGE, age);
person.putBoolean(Person.ISMALE, isMale);
return person;
}
Similarly, you can get one or more stored values of the Bundle using one of the person.get...() methods. Furthermore, instead of creating an array of Persons you can now create a Bundle of persons using bundle.putBundle()! You just need to find the right key-scheme, here you could either provide an id for each person or just use their names as key (although the key array has to be passed seperately). And what do we get from all this? Well we can now just call intent.putBundleExtra(person) and voilà, we've passed it to another app component.
Resourcing is not outsourcing
One of Android's big advantages is its exceptional resource system. The fact that all your Strings and values are saved in a separate xml file makes your app not only easier to translate, but also keeps your code cleaner and lets you have a complete overview of what amount of constants you use. But you can go further than that. The resources allow for entirely different configurations depending on screen size, resolution, orientation, location and api-level! To learn more about how this can be done, head over to the Android devoper guides.
One thing I wanted to highlight is that it used to be quite hard to make a consistent interface and still support Android 2.1 and above. That is not the case any more since we now the the continuously improving AppCompat library. It is even useful for apps targeting only ICS and above because it contains bugfixes and improvements for those versions as well. Using this library is the best way to get the holo theme and its ActionBar in your app, although if you could also try ActionBarSherlock to accomplish the latter.
Click to expand...
Click to collapse

Think D.I.P
So what's this strange thing they call dip? And why do we even bother using it, we have had pixels (pix) since the beginning of programming. First things first, try to avoid pixels on Android. On almost every other platform using the smallest unit that's available is a great thing in layouts, but not so much on Android where apps can run on devices as small as a smartwatch up to 2k tablets. The problem is that you can't be sure if a single pixel is as small it can barely be seen or as large as a few millimeters. That is why we have the standard-sized density-independent-pixels (dip or dp in short) where 48 dips are roughly equivalent to 9mm, the convenient size of a touchable area (e.g. a Button). Great, then how many dips is my screen wide/high? That is not an easy question since it varies as well. Phones usually have around 320dips (at the smallest width) but larger screens can fit more so on tablets you have 600dips or more. Try to understand this documentation and don't be confused with the abbreviations dp, dip and DPI – dp and dip are the same and DPI is dots per inch (similar to pixels per inch), the screen density!
The reason why I'm bringing this up here is advice you to understand and always think in dips, never in pixels. Even on a Canvas, where there is only methods for pixels, don't think “ok I draw my text 20 pixels from the left edge and 50 from the top so canvas.drawText(“text”, 20, 50, myPaint);”. Start to think in dips: “I have to draw it 16dip from the left edge and 24dip from the top!” But how to convert it to pixels so it can be actually drawn onto the Canvas? It really is a shame there is no method in the Context class to directly convert dip to pixels, so here's the one I use:
Java:
private DisplayMetrics displayMetrics;
/**
* Converts a given dip (density independent pixel) value to its corresponding pixel value.
* @param dips The dip value to convert, as float.
* @return The pixel value, as int.
*/
private int dipToPix(float dips) {
if(displayMetrics == null)
displayMetrics = getResources().getDisplayMetrics();
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dips, displayMetrics);
}
And a side note on sp, that is the scale-independent text size. Try to use it as far as you can, for instance in layout resources. But just in case of needing the actual size, use the same method because sp is computed almost the same as dip.
Hyperthreading is not that complex
An app's UI (or “main”) thread is its beating heart, and we don't want to slow down what's powering us if there are other options available, right? If you don't follow the rule of not performing any time consuming tasks in the default thread you'll end up with what all developers fear: The “App is Not Responding” dialog – in short ANR. When users see this, they can get really mad, from just force closing your app and uninstalls to 1-star ratings everything is to be expected. Because it is crucial to know about Threads (and Processes), carefully read the guide in the Android docs about it, pay special attention to the two simple rules in Android threading:
1. Do not block the UI thread
2. Do not access the Android UI toolkit from outside the UI thread
Click to expand...
Click to collapse
Let's take a look at the first one, what are you going to do instead if you need to accomplish an expensive task like web requests, complex calculations, Bitmap operations, database queries and I/O management?
Well the answer is not as simple as it may seem since it depends on what and how often you will be doing that task. A task that is performed once per activity launch is almost always wrapped into an AsyncTask, a class which is heavily optimized and integrated into the system. If you know how it works it is a very powerful tool since it does most of the heavy lifting for you, so let me show you how to do it:
You start by extending the AsyncTask class like so:
Java:
private class MyAsyncTask extends AsyncTask<Param, Progress, Result> { //...
Usual stuff, except for the weird <Param, Progress, Result> thing. It is actually not that hard, these are all just type declarations of variables your methods want to use. Thus, the first one is the type of starting parameter you want. Think of it as if you wrote your task in a separate method without access to any instance variables, what data would it need to work (what params would you pass to it in the parentheses). The second one is actually often unused and is needed if you want to return a var indicating progress on the task so it can be published e.g. in a ProgressBar. Lastly, Result is (you may have guessed it) the type of variable you want your task to return, to be published in the UI as well. A typical configuration would be <Uri, Integer, String> for a task reading a file. Note that these have to be objects, so for primitives you'd have to use their respective Java classes like Integer or Double. But that also means that a Bundle can be used as well so we know how to pass multiple parameters now! And there is another way as well, look at the overridden methods:
Java:
protected Long doInBackground(Uri... uris) {
// do your expensive work here, it runs on a separate thread!
}
protected void onProgressUpdate(Integer... progress) {
}
You'll notice the three dots after Uri and Integer. To keep it simple, treat it as an array, so to access your value call uris[0] and progress[0], respectively. The reason for it being an array is that you can start the same AsyncTask with multiple parameters of the same task:
Java:
new MyAsyncTask().execute(uri1, uri2, uri3, uri4);
This is extremely useful in this case to read multiple files at the same time (don't be confused with the configuration in <> above, the param(s) passed to execute() are joined together in the Param array).
A side note on progress here, if you want to publish progress during your doInBackground(), just call publishProgress(Progress) and override onProgressUpdate() to publish the changes in the UI. Similarly with onPostExecute(), you'll probably want to override that method as well to show your awesome result to the user.
What you need to keep in mind is how AsyncTask is handled internally, read the section “The 4 steps” in the AsyncTask documentation carefully. In fact, doInBackground() is method you need to think about the most since it is encapsulated in a separate thread with no access to the UI or methods in your activity.
Because AsyncTask is limited to one operation and should only run up to a few seconds, there are a couple of other ways to do tasks in the background like a second Thread and helpers such as Handlers. The Handlers are needed to access the UI from the worker threads, still following the second rule above. If you want to read more here's an awesome Vogella tutorial about it.
Fragment-tation
This next one is really a good style of development and can save a lot of work if you provide layouts for both phones and tablets (which you definitely should). The basic theme of using Fragments is to follow the divide and conquer technique, which dates back to ancient time in Babylonia. Thus, the idea is to have one large problem (a user interface and its data for both tablets and smartphones) and split it into multiple simpler ones (in this case having one or more Fragments for each screen on phones). Especially in multi-pane layouts, for instance in the settings app, Fragments are a wonderful tool to avoid the use of two different activities, one for phones and one for tablets. The steps to implement them in your app are pretty simple and there are already some neat guides like the one in the documentation and Vogella's one. An additional use-case for Fragments is to retain an AsyncTask when rotating the screen. You would create a Fragment without layout in the UI and call setRetainInstance() on it. Any expensive AsyncTask can then be started inside that Fragment and is not stopped when the activity is recreated during an orientation change.
Memory-zing is unneeded
But it is not only performance, layout and style which can be improved, think about memory usage for a second. It goes hand in hand with performance since an app which consumes unnecessary memory (garbage) will be slowed down by the garbage collector (GC) thrown in from the system, trying heavily to free some RAM. On Android this is extremely important, since a garbage collector running intensely on a single or dual core processor can really slow down the device's performance. That is also why method calls and object creation are so expensive and have to be used with caution – the overhead they produce bumps up the memory usage. And there is one specific case where you can really have a problem with your memory, a so-called memory leak. What this means is that some part of your app is holding on to a very large object like a Resources or database one or even a whole Activity or Fragment. The problem is that the GC can only collect objects which aren't referenced from an active part of your app so this means it can't be collected and ends up blocking all your available memory. Such a leak is something you want to avoid at all times and there are some awesome tools to find out if you have one. All you need to know about that and memory optimizations in general is covered in this amazing I/O talk, so I advice you to watch that!
Most of the time there is no real need for reducing method calls and object creation because the GC is fast enough. But there is one step where it is crucial to avoid it, methods which are called on every redraw like the onDraw() method of a View, which I'll cover in the following.
Optimizing performance? onDraw!
In your custom views the most important method to think about is the onDraw() method since that is where everything that is visible to the user is rendered. A lot can be gained (or lost) in that crucial step, so try to follow the performance guidelines posted earlier as close as possible. Especially, pay attention to the object creation, creating a few objects in onDraw() might not seem expensive, but the memory footprint and the garbage collector usage will be tremendous. When drawing on a Canvas for instance, a common pattern would be to check if the paint instance variable is null before drawing:
Java:
if(paint == null) {
paint = new Paint();
paint.setColor(drawingColor); // ...
}
That code would typically be placed in the surfaceCreated(), but could also be in the onDraw() if you are lazy and want to keep it in one place. . While object creation is not the only thing you can improve performance-wise, just try to apply the aspects I wrote about in the beginning, especially those loops!
One thing I have to point out about performance before moving on to some links that might help you is that before trying to optimize your app in some arbitrary way (and totally destroying readability) measure upfront. That means use the tools mentioned in this great I/O talk covering graphics and performance to get a sense whether your app is really driving close to that 16 millisecond threshold to get the desired 60 frames. Additionally, it might be a good idea to not only test it on the high end devices (#Nexus5) but also those with a high “resolution/processing” value such as the first tablets with 1080p resolution. Thus, only start tweaking performance if you know you take too much time, then try to nail down the time consuming methods. And always try to improve readability and simplicity, not only for us when posting pieces of your code here but also for yourself: it helps getting into the flow if you see that your code is readable and nice .
Additional resources
If you can spare some time and want to know more about how to build awesome apps and UIs, check out the Android sessions at Google I/O 13, especially the Android UI design talk and the Android Protips 3 (but the first and second Protips were great as well as the beginner's talk from 2010). There is also the Android developers blog and the Vogella tutorials. As usual, the Android developers page is always a great resource and Google is still your friend (use “android dev” together with your question to get better results). For more info about general Java performance improvements, I found this nice pdf outlining how you can improve your code even further.
Click to expand...
Click to collapse
</guide>
Anyway, that's about it. It has really become a way too long collection of links and videos so I hope it was useful and perhaps made you rethink your code . If you've got any comments or suggestions feel free to post them here, helps a lot.
This guide was featured on the portal on February 4th (thanks eagleeyetom!)

To be continued...

One Thanks isn't enough!

Great writeup! Thanks!

Wow man such a good information muchly appreciated great job!
Sent from my Nexus 4 using Tapatalk

Wow, great collection of tips and tricks. Much appreciated!!

Handy tips
awesome job dude.was really helpful!!!!!:good:

Great article! Please keep going. :good:

Simply awesome...great work.
Sent from my SAMSUNG-SGH-T989 using Tapatalk

Thanks for this great writeup! The android specific tips are really interesting.

Great guide (again). :good:
Just one thing I want to add: I still prefer wrapper classes which implement Parcelable. In fact, it's not that difficult and you should be able to do it in a few minutes. Have a look at the example code here: http://developer.android.com/reference/android/os/Parcelable.html That's it.
I've also found an IntelliJ plugin for that purpose (but I haven't tried it yet): https://github.com/mcharmas/android-parcelable-intellij-plugin
That wasn't meant to degrade your work though. It's an amazing guide.

nikwen said:
Great guide (again). :good:
Just one thing I want to add: I still prefer wrapper classes which implement Parcelable. In fact, it's not that difficult and you should be able to do it in a few minutes. Have a look at the example code here: http://developer.android.com/reference/android/os/Parcelable.html That's it.
I've also found an IntelliJ plugin for that purpose (but I haven't tried it yet): https://github.com/mcharmas/android-parcelable-intellij-plugin
That wasn't meant to degrade your work though. It's an amazing guide.
Click to expand...
Click to collapse
Good point and thanks!
Having a closer look at it, implementing Parcelable is not that much work and it would definetely be the more advanced way. Bundle is basically just another layer that makes things a bit easier for the start (and no typecasting) and I found that it can really shine with a singleton class holding the keys and the getters and setters (which have an additional param, the Bundle). For a beginner who just wants to save some values (possibly keeping the keys in the activity or even hardcoded) using the Bundle is a lot easier. Yet again, TIMTOWTDI

Thank you!

Hey Simplicity, after few years there is something you would change? Maybe dagger2, kotlin, rxjava changed the game, as really open question what do you think about?

The question might be a bit off topic, i am working on a root app development but i am pretty confused that how should i get the busbox commands to run on button press, i have given the path and everything but how am i supposed to create a busbox file in data/data/package/files.
This part is confusing me I am not able to create that file, should i keep it in res while creating the app ? And also one last question, from where can i get that busbox file with all its command. Please help, I'm sorry if this is the wrong forum I'm new to posting questions and also to app development .

playing audio files in an app

Hi there
I am desperate for advice and support on how to develop an android app that plays music audio files.
The app itself would have a home screen, about screen and a tracks screen.
The user when they navigate to tracks screen would have a list view of music audio files they can listen to on their android device.
The music audio file itself can either be stored in a SQL server database or ftp site , I don't know what would be best in terms of delivering optimal performance for end user?
The app would be like a service that would just play in the back ground allowing users to use their phone whilst listening to the music track(s).
My problems are:
- how can I actually develop this?
- there are no tutorials on the net, all music playing apps on YouTube, stack overflow and other websites do not show how to read music from SQL or ftp server.
I would be eternally grateful to anyone who could kindly advise me:
- best way to store each music audio file? Ftp or SQL
- in any case SQL would have to be used I believe to store the weblinks if I were to use FTP
- each music file of which there are around 150-180 is around 100mb in size and is of mp3 quality
Please , please , please can you help me develop this? Or guide me so I may be able to do it.
Please advise me on best way to set this up and get me started...
Thank you in advance

xirokx said:
Hi there
I am desperate for advice and support on how to develop an android app that plays music audio files.
The app itself would have a home screen, about screen and a tracks screen.
The user when they navigate to tracks screen would have a list view of music audio files they can listen to on their android device.
The music audio file itself can either be stored in a SQL server database or ftp site , I don't know what would be best in terms of delivering optimal performance for end user?
The app would be like a service that would just play in the back ground allowing users to use their phone whilst listening to the music track(s).
My problems are:
- how can I actually develop this?
- there are no tutorials on the net, all music playing apps on YouTube, stack overflow and other websites do not show how to read music from SQL or ftp server.
I would be eternally grateful to anyone who could kindly advise me:
- best way to store each music audio file? Ftp or SQL
- in any case SQL would have to be used I believe to store the weblinks if I were to use FTP
- each music file of which there are around 150-180 is around 100mb in size and is of mp3 quality
Please , please , please can you help me develop this? Or guide me so I may be able to do it.
Please advise me on best way to set this up and get me started...
Thank you in advance
Click to expand...
Click to collapse
sounds like you need to do lots more research and maybe a few tutorials for a better understanding. I would suspect 99% of developers would host file though http/s (not ftp) and yes all song info and metadata in SQL and delivered though php.
Binary Storage in SQL is not out of the question using BLOBS but not well suited in your case.
hope that helps, sounds simple enough

sounds like you need to do lots more research and maybe a few tutorials for a better understanding.
Click to expand...
Click to collapse
thanks for your reply
i have tried looking for tutorials for hours on end and its a very niche area, i could not find any.....do you know of any? have you tried looking for tutorials?
I would suspect 99% of developers would host file though http/s (not ftp) and yes all song info and metadata in SQL and delivered though php.
Click to expand...
Click to collapse
how do you host mp3 files using HTTPs ?
sounds simple enough
Click to expand...
Click to collapse
if its that simple, perhaps you would not mind guiding me to acheive it?
the page in the app which contains the mp3 files would have a listview or gridview with the names of the mp3s so when user clicks on them the mp3 plays in the background...
perhaps you can create an example if possible? i would be so grateful.
thank you

xirokx said:
i have tried looking for tutorials for hours on end and its a very niche area, i could not find any.....do you know of any? have you tried looking for tutorials?
Click to expand...
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You will never find a tutorial to do an exact app for what you want But you will find 1000's of how to store and use data from a database, 1000's for how to use mySQL and php in android, 1000's for listviews and gridviews powered by adapters and data and again 1000's or hundreds on how to stream audio from web servers using android
xirokx said:
how do you host mp3 files using HTTPs ?
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Click to collapse
upload them ? not sure what your question is here, you place the file on the server and use the URL ?
xirokx said:
if its that simple, perhaps you would not mind guiding me to achieve it?
the page in the app which contains the mp3 files would have a listview or gridview with the names of the mp3s so when user clicks on them the mp3 plays in the background...
perhaps you can create an example if possible? i would be so grateful.
thank you
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It contains such a generic set of tasks you really dont need me to write it for you.... I'm always happy to answer direct specific questions, but you will seldom get an answer for "how do I do x app"... but like I said, what you want is very common, so there is tonnes of resource online

thanks for your reply
You will never find a tutorial to do an exact app for what you want But you will find 1000's of how to store and use data from a database, 1000's for how to use mySQL and php in android, 1000's for listviews and gridviews powered by adapters and data and again 1000's or hundreds on how to stream audio from web servers using android
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Click to collapse
If only the world was perfect and I could find an "exact" tutorial.....If I thought it was that easy I would never have started my thread.
really? 1000s or 100s.....yet you cannot point me to one?
It contains such a generic set of tasks you really dont need me to write it for you.... I'm always happy to answer direct specific questions, but you will seldom get an answer for "how do I do x app"... but like I said, what you want is very common, so there is tonnes of resource online
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if it is that generic and simple, I do not understand why you cannot guide me more, at least to the 1000's or 100's of tutorials you claim that exist and especially as I have mentioned I cannot find them.
Try and see it from my point of view, I am new to this, trying, well actually REALLY REALLY want to learn, have spent hours researching for adhoc tutorials that will enable me to grasp the "generic" concept and have not found much / anything to help me.
Then you come along and make such a bold claim basically saying its "simple and easy, generic and quite straightforward" yet you cannot backup your claim by providing any of these "easy to find, 1000's or 100s tutorials" and are not willing to help any more then this.
Personally if I thought something was that easy, how much of my valuable time is it really going to take me, to provide someone who wants to learn with a few lines of code to get them started, especially after making such BOLD claims....
If I was not willing to, I would not even bother replying, it would have been far more beneficial if you responded with some example code rather then claiming how simple it was to do, I see no evidence that is it so easy only your claims...
Thanks for your time

Seriously though, this is me using google
http://developer.android.com/guide/topics/data/data-storage.html
http://developer.android.com/training/basics/data-storage/databases.html
http://www.vogella.com/tutorials/AndroidSQLite/article.html
http://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/
http://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/
http://www.mybringback.com/tutorial...-using-remote-databases-php-and-mysql-part-1/
http://forum.xda-developers.com/showthread.php?t=2325799
http://developer.android.com/guide/topics/media/mediaplayer.html
http://stackoverflow.com/questions/18174068/how-to-play-the-online-streaming-radio-in-android
http://stackoverflow.com/questions/1965784/streaming-audio-from-a-url-in-android-using-mediaplayer
if you use google you will find 1000's more results, they were just the top ones really, not sure why you cant find any...seriously pages and pages of relevant results, what were you actually searching for ? as in search terms ... maybe thats the prob ?
Also yes it is generic and yes almost every app uses those components and has had to complete those tasks. Trust me on this, remote database + online resources are in 90% of apps But it's the tasks that have 1000s of tutorials and reference, not the app.... like i say "android database tutorial", "android mysql online database","android media stream url"
hope that helps

thanks alot....I will check them out and get back to you
so grateful for your help

maybe you can solve this, perhaps its "challenging" enough for ya
this is my android java code that a) connects to my db b) uses the Name field from my db to populate a listview in my app c) when any single listview item is selected, it uses the name in the listview matches it to the dbName and plays the dbFile which contain a URL to where the mp3 is stored:
Code:
private void connect() {
List<String> r = new ArrayList<String>();
ArrayAdapter<String>adapter=new ArrayAdapter<String>(getApplicationContext(), android.R.layout.simple_list_item_1,r);
final ListView list=(ListView)findViewById(R.id.listView1);
try {
DefaultHttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet("myServer/android/files.php");
HttpResponse response = client.execute(request);
HttpEntity entity=response.getEntity();
data=EntityUtils.toString(entity);
Log.e("STRING", data);
try {
JSONObject jsonResponse = new JSONObject(data);
JSONArray jsonMainNode = jsonResponse.optJSONArray("mp3s");
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
ID = jsonChildNode.getInt("ID");
name = jsonChildNode.getString("Name");
FileName = Uri.parse(jsonChildNode.getString("FileName"));
Log.e("STRING", name);
//r.add(ID);
r.add(name);
list.setAdapter(adapter);
list.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,int position, long id) {
MediaPlayer mp = new MediaPlayer();
try{
mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
mp.setDataSource(getApplicationContext(), FileName);
mp.prepare();
mp.start();
}
catch(IOException e)
{
System.out.println(e);
}
}
});
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (ClientProtocolException e) {
Log.d("HTTPCLIENT", e.getLocalizedMessage());
} catch (IOException e) {
Log.d("HTTPCLIENT", e.getLocalizedMessage());
}
}
Problem is:
- It doesnt open mediaplayer or streaming player on the emulator
- If track 1 is playing and I click on track 3 it plays both tracks simulateously
- as there is no media/stream player view you cannot pause/stop/play the track that is being played
pls help me fix these issues, if you can
thanks
p.s. I did use your links to get me this far, now I am genuinely stuck and would really appreciate a hand
thanks appreciate it

xirokx said:
Problem is:
- It doesnt open mediaplayer or streaming player on the emulator
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Dont work with the emulator at all, I only use real devices, but if you mean the media player app, then thats due to you not using it. You're using the media player class.
xirokx said:
- If track 1 is playing and I click on track 3 it plays both tracks simulateously
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Thats cause you create another instance that every click (or new instance rather). I would assume that you just should have 1 and stop/reuse it.
xirokx said:
- as there is no media/stream player view you cannot pause/stop/play the track that is being played
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Well you would create buttons to do that yourself.

I am now debugging my app on my device
I have changed the code a little so only 1 file plays at any one time and it works....
list.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,int position, long id) {
//playAudio(FileName);
Uri uri = FileName;
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
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Click to collapse
However when I click on the list item, a menu opens up asking which browser I want to play the file in....when instead it should open a list of mediaplayers for me to play the file in.
How can I change it?
Thanks for your help.

xirokx said:
I am now debugging my app on my device
I have changed the code a little so only 1 file plays at any one time and it works....
However when I click on the list item, a menu opens up asking which browser I want to play the file in....when instead it should open a list of mediaplayers for me to play the file in.
How can I change it?
Thanks for your help.
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Click to collapse
well thats the way it will work if down to the user not choosing a default and also the way you set it up.... I do reccomend you read the android docs like http://developer.android.com/guide/components/intents-filters.html
it will help when asking question and most of the time you wont have to ask cause the answers are there.

Database Users

welcome