stealthcopter.com

When releasing an android application it is often desirable to release your application to the largest amount of users as possible. By developing an application with android 1.5 as the target, later versions are automatically supported (1.6, 2.0, and 2.1). However different screen-sizes were introduced with android 1.6 so by default an application will not support smaller screens (larger screens are automatically supported).

Android Versions Marketshare
The image below shows the current market share for the different version of android:

Android Platform	Percentage of Devices
1.1	0.3%
1.5	27.7%
1.6	54.2%
2.0	2.9%
2.0.1	14.8%

Devices with small screens include the following phones T-Mobile G1, Samsung I7500, and the HTC Tattoo. Unfortunately I cannot find any statistics regarding the percentage of small screen android users (if you can please let me know). However as the fix is very simple it seems stupid not to.

Adding Support
To add support for different screen sizes we need to add a supports-screens tag in our android_manifest.xml. This should look like the following:

  <supports-screens
          android:largeScreens="true"
          android:normalScreens="true"
          android:smallScreens="true"
          android:anyDensity="false" />

This tells android that the application should work on large, normal and small screens. Note that only setting small to false will prevent it from been visible in the market to small screened phones, for normal and large it will simply change the method of which android interprets the display of this application. anyDensity fix me

However in order to use the supports-screens tag the target of your application must be android 1.6 (or Sdk version 4). We can allow our program which is now targetted for android 1.6 still be avaliable for android 1.5 (Sdk version 3) by adding android:minSdkVersion=”3″ to our uses-sdk tag.

<uses-sdk android:minSdkVersion="3" android:targetSdkVersion="4"/>

Now your application can be built for 1.6 supporting smaller screen sizes and still work on 1.5.

Demonstration
Below are screenshots from two AVD’s, one with a normal screen size, and one with a small screen size:

Note: Eclipse bug
Unfortunately eclipse currently does not acknowledge minSdkVersion and will not give you the option to test your application in any android virtual devices (AVD’s), while this is not fixed you can manually install the package into your AVD. For this you need to know the name of your emulator instance, to do this first run the AVD and then use the followin command to find out the name.

$adb devices
List of devices attached
emulator-5554   device

So we can see that the emulator instance I need is called emulator-5554. We can now use adb to install a package into this emulator. The below example shows installing wordcubefree from the bin folder in my project to my AVD using adb.

adb -s emulator-5554 install ~/android/workspace/WordCubeFree/bin/WordCubeFree.apk
1019 KB/s (39683 bytes in 0.038s)
Can't dispatch DDM chunk 46454154: no handler defined
Can't dispatch DDM chunk 4d505251: no handler defined
        pkg: /data/local/tmp/WordCubeFree.apk
Success

Note that this will fail if the application is already installed and you will need to uninstall the application before using this command (if anyone knows a switch to force install or alternative method please let me know)

Going Further
It is possible to delve into this is more detail by providing layouts for small, medium and large screen sizes. This can be explored in more detail in the google dev support guide

When creating any non-trivial program using a versioning system is essential, especially when working in part of a group. This guide aims to be a quick tutorial to the SVN (subversion) tool for versioning and how to use it with an android project.

Assumptions

• You will need SVN installed on your computer. This can be done using your package manager or by the following command in ubuntu / debian based systems:

  sudo apt-get install subversion

• You already have an SVN repository configured. If not please view a tutorial like this or if you have a nice webhost like me (thanks dreamhost ) there may be a simple tool to do this automatically for you in your panel.

Note
Don’t include the files inside /bin or /gen as they are just build from the source code and will simply fill up a lot space in your SVN. But do include the folders themselves as the project will fail to build without them.

Command line (recommended)
For SVN, I am a great fan of the command line. From the few SVN GUI applications that I have used in the past I can recommend Turtoise SVN for windows and kdesvn for linux (kde) but I still prefer the command line.

The following code will checkout the project from your server. This will create a new folder called “projectname” on your computer and download the project from your server (at this point it is most likely an empty folder).

# Checkout the SVN directory
svn co svn.yourdomain.com/projectname projectname

You can then copy or create your android project in this directory. In our project folder there are two folders which contain generated files (as opposed to source files) there is no point uploading these to the svn as you will simply take up space and bandwidth. Before you decided to upload your changes to the server you should empty the bin and gen folders:

# Empty bin and gen folders
rm -rf ./projectname/bin/*
rm -rf ./projectname/gen/*

Each time you add a new file to the project you will need to add (`svn add filename` for single files or `svn add *` for all files):

# Tell SVN we want to be versioning these files
svn add projectname/*

When you are happy with your changes you can commit (`svn commit -m “message”`) your changes to the svn to create a new version, it is mandatory to include a message with each revision and it is best to be as detailed as possible with the changes made. This makes it much easier to hunt down where a bug or regression was introduced.

# Save the changes and upload to repository
svn commit -m "Initial import of projectname"

Each time you commit or wish to upgrade what is stored locally to the latest version on the server you need to use the following:

# Update the locally stored version
svn update projectname

Further points
Eclipse has a plugin to manage SVN download and install instructions can be found here.

In my android apps I was getting annoying problems that whilst playing sound the volume buttons would control the media volume, but when no sound was playing they would control the ringtone volume. I found the following by trial and error, hopefully this post will help people with the same problem.

This is done by placing a call of setVolumeControlStream in the onCreate part of your activity which takes on of the following values

• AudioManager.STREAM_MUSIC
• AudioManager.STREAM_RING
• AudioManager.STREAM_ALARM
• AudioManager.STREAM_NOTIFICATION
• AudioManager.STREAM_SYSTEM
• AudioManager.STREAM_VOICECALL

Below shows the code required to set your applications default volume control to any of the above values:

Media Volume

this.setVolumeControlStream(AudioManager.STREAM_MUSIC);

Ringtone Volume

this.setVolumeControlStream(AudioManager.STREAM_RING);

Alarm Volume

this.setVolumeControlStream(AudioManager.STREAM_ALARM);

Notification Volume

this.setVolumeControlStream(AudioManager.STREAM_NOTIFICATION);

System Volume

this.setVolumeControlStream(AudioManager.STREAM_SYSTEM);

Voicecall Volume

this.setVolumeControlStream(AudioManager.STREAM_VOICECALL);

I imagine this is also possible via and XML settings, if anyone knows of this I’d be very grateful to know how!

Quite a few people have been asking how to save a file to the SD card in order to register it as a ringtone. The following example creates a function that will save a resource to the SD card (ie: from R.raw.soundfile to /sdcard/media/audio/ringtones/soundfile.wav) and register it as a ringtone.

I have split this example into two parts, the first part goes through the code a section at a time with a brief explanation of what it does, the second half is just the code that you can copy and paste and then edit to your hearts content.

Parts

We first setup our function to return a boolean depicting if we have failed or if we are successful. We accept in an integer which corresponds to the raw sound file.

public boolean saveas(int ressound){

}

So this function would be called in the following fashion:

saveas(R.raw.soundfile);

or utilising its boolean return:

if (saveas(R.raw.soundfile)){
// Code if successful
}
else
{
// Code if unsuccessful
}

The following chunk of code creates an inputstream from the raw sound resource and loads it into a buffer. We add in the mandatory try/catch clause around these operations and return false if an exception is raised (to indicate failure to the rest of our program and to prevent trying to continue act upon this sound).

 byte[] buffer=null;
 InputStream fIn = getBaseContext().getResources().openRawResource(ressound);
 int size=0;

 try {
  size = fIn.available();
  buffer = new byte[size];
  fIn.read(buffer);
  fIn.close();
 } catch (IOException e) {
  // TODO Auto-generated catch block
  return false;
 }

The following saves the buffer to a file on the SD card. It first ensures the folder exists and if not it is created. Then as before the writing operations are surrounded with try/catches

 String path="/sdcard/media/audio/ringtones/";
 String filename="examplefile"+".wav";

 boolean exists = (new File(path)).exists();
 if (!exists){new File(path).mkdirs();}

 FileOutputStream save;
 try {
  save = new FileOutputStream(path+filename);
  save.write(buffer);
  save.flush();
  save.close();
 } catch (FileNotFoundException e) {
  // TODO Auto-generated catch block
  return false;
 } catch (IOException e) {
  // TODO Auto-generated catch block
  return false;
 }

The following code sends an intent to tell the Media Scanner that we have added a new file, and sets up its properties in the media database:

 sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.parse("file://"+path+filename)));

 File k = new File(path, filename);

 ContentValues values = new ContentValues();
 values.put(MediaStore.MediaColumns.DATA, k.getAbsolutePath());
 values.put(MediaStore.MediaColumns.TITLE, "exampletitle");
 values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/wav");
 values.put(MediaStore.Audio.Media.ARTIST, "cssounds ");
 values.put(MediaStore.Audio.Media.IS_RINGTONE, true);
 values.put(MediaStore.Audio.Media.IS_NOTIFICATION, true);
 values.put(MediaStore.Audio.Media.IS_ALARM, true);
 values.put(MediaStore.Audio.Media.IS_MUSIC, false);

 //Insert it into the database
 this.getContentResolver().insert(MediaStore.Audio.Media.getContentUriForPath(k.getAbsolutePath()), values);

Final code
Putting all this code together gives us our final functions:

public boolean saveas(int ressound){
 byte[] buffer=null;
 InputStream fIn = getBaseContext().getResources().openRawResource(ressound);
 int size=0;

 try {
  size = fIn.available();
  buffer = new byte[size];
  fIn.read(buffer);
  fIn.close();
 } catch (IOException e) {
  // TODO Auto-generated catch block
  return false;
 }

 String path="/sdcard/media/audio/ringtones/";
 String filename="examplefile"+".wav";

 boolean exists = (new File(path)).exists();
 if (!exists){new File(path).mkdirs();}

 FileOutputStream save;
 try {
  save = new FileOutputStream(path+filename);
  save.write(buffer);
  save.flush();
  save.close();
 } catch (FileNotFoundException e) {
  // TODO Auto-generated catch block
  return false;
 } catch (IOException e) {
  // TODO Auto-generated catch block
  return false;
 }    

 sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.parse("file://"+path+filename)));

 File k = new File(path, filename);

 ContentValues values = new ContentValues();
 values.put(MediaStore.MediaColumns.DATA, k.getAbsolutePath());
 values.put(MediaStore.MediaColumns.TITLE, "exampletitle");
 values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/wav");
 values.put(MediaStore.Audio.Media.ARTIST, "cssounds ");
 values.put(MediaStore.Audio.Media.IS_RINGTONE, true);
 values.put(MediaStore.Audio.Media.IS_NOTIFICATION, true);
 values.put(MediaStore.Audio.Media.IS_ALARM, true);
 values.put(MediaStore.Audio.Media.IS_MUSIC, false);

 //Insert it into the database
 this.getContentResolver().insert(MediaStore.Audio.Media.getContentUriForPath(k.getAbsolutePath()), values);

 return true;
}

Comments, suggestions etc. are always welcome. Hope this has been helpful.

When using TableLayout with LayoutParams Eclipse will automatically (and wrongly) add the following import:

import android.view.ViewGroup.LayoutParams;

However if you try to use this you will notice that nothing changes. You need to replace the import with the ollowingL

import android.widget.TableRow.LayoutParams;

Now if you rerun your code, you will see that your tables are updating. See below for an example of the code to generate a table

int sizey=10;
int sizex=10;
int btnwidth=24;
TableLayout tl = (TableLayout)findViewById(R.id.MyTableLayout); 

for (int y=0;y<sizey;y++){

// Rows
TableRow tr = new TableRow(this);
tr.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));

//Cells
for (int x=0;x<sizex;x++){
// Create new cell
	// new button
	Button b = new Button(this);
	b.setText(x+""+y);
	b.setLayoutParams(new LayoutParams(
		LayoutParams.FILL_PARENT,
		LayoutParams.WRAP_CONTENT));
	b.setHeight(btnwidth);
	b.setBackgroundResource(R.drawable.btn_blue);
	b.setOnClickListener(new PegOnClickListener(y,x));
	// add button to row
	tr.addView(b);
	}
// add row to layout
tl.addView(tr,new TableLayout.LayoutParams(
LayoutParams.FILL_PARENT,
LayoutParams.WRAP_CONTENT));
}
}

The android SDK has lots of nice goodies built in to make your applications look sexier. One such feature is the blurring of windows. This effect looks particularly nice if a background window is blurred while a dialog box is shown above which can really make it stand out. Below shows the application such an example; on the left is the default about box (for WordCube Pro) and on the right is with added blur and no dimming.

I am using the AlterDialog.Builder to create my dialog, however this method will work with all kinds of dialog providing you can access it via getWindow.

   dialog = new AlertDialog.Builder(WordCube.this)
   .setTitle(WordCube.this.getResources().getString(R.string.app_name))
   .setMessage(s)
   .setIcon(R.drawable.logo)
   .setPositiveButton(R.string.btn_close, null)
   .show();

Below shows the code needed to add blur and remove dimming of the background (as I think the blur looks nicer when the background is well lit).

WindowManager.LayoutParams lp = dialog.getWindow().getAttributes();
lp.dimAmount=0.0f;
dialog.getWindow().setAttributes(lp);
dialog.getWindow().addFlags(WindowManager.LayoutParams.FLAG_BLUR_BEHIND);

The blur is simply created using the last line (line 4) which sets a flag for the dialog telling android that we want windows below this one to be blurred. To achieve the dimming, we need to retrieve the layout parameters for the dialog window, set the dim amount to zero, update these parameters with setAttributes (lines 1-3).

Any comments, questions, or improvements please let me know.

This post builds upon the ideas shown in this post to create a complete function that will do the follow:

• Accept a string input for the message
• Try to open twidroidpro to send this tweet
• If failed, try to open twidroid to send this tweet
• If failed, bring up a list of applications that can send this information
• Return a boolean indicating success of displaying the intent

Code

public boolean intentTwitter(String message){
 // Boolean to show if we succeeded or not
 // we assume we did until proven otherwise.
 boolean success=true;

 //Try twidroidpro first
 Intent intent = new Intent("com.twidroidpro.SendTweet");
 intent.putExtra("com.twidroidpro.extra.MESSAGE", message);
 intent.setType("application/twitter");
   try{
    startActivityForResult(intent, 1);
   }
   catch(ActivityNotFoundException e){
    success=false;
   }

 // Then twidroid if we failed
 if (!success){
  success=true;
  intent = new Intent("com.twidroid.SendTweet");
  intent.putExtra("com.twidroid.extra.MESSAGE", message);
  intent.setType("application/twitter");
    try{
     startActivityForResult(intent, 1);
    }
    catch(ActivityNotFoundException e){
     success=false;
    }
 }

 //Then send general intent if we failed again
 if (!success){
  success=true;
   try {
    intent = new Intent(Intent.ACTION_SEND);
    intent.putExtra(Intent.EXTRA_TEXT, d);
    intent.setType("application/twitter");
    startActivity(Intent.createChooser(intent, null));
   } catch (ActivityNotFoundException e) {
    success=false;
   }
 }
// return indicating if we were successful in bringing up an intent
// of some description
return success;
}

Example
Below is a screenshot from the wordcube (available on market) application using this function to make the application interact with twitter.

What’s next?
In a future post I will be demonstrating how to interact with the android market, this can be use in conjunction with something similar to above to try and run a program and if the program is not installed the user can be taken to the market to download a program.

A soundboard is a very simple application to make, and I was given the idea to make a counter-strike 1.6 version by a friend. It seemed like a good idea as no one had made one yet, and it’s quite hard to find something that hasn’t already been done before.

The buttons are aligned in a grid view, with the buttons made transparent so that the background can be seen.

I am very pleased with the final look of the app, however it was getting poor reviews due to people wanting to save the sounds for use as a ringtone. To alleviate this problem I have updated the app to have this option as a context menu avaliable by long pressing on a button. This will then save the file on the sd card and update the mediastore to tell android a new ringtone and notification has been added.

The code to load a ringtone into android from an application is shown below. If you see any problems with this code, or have an improvements please let me know!

File k = new File(path, filename);

ContentValues values = new ContentValues();
values.put(MediaStore.MediaColumns.DATA, k.getAbsolutePath());
values.put(MediaStore.MediaColumns.TITLE, filesnames[pos]);
values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/wav");
values.put(MediaStore.Audio.Media.ARTIST, "cssounds ");
values.put(MediaStore.Audio.Media.IS_RINGTONE, true);
values.put(MediaStore.Audio.Media.IS_NOTIFICATION, true);
values.put(MediaStore.Audio.Media.IS_ALARM, true);
values.put(MediaStore.Audio.Media.IS_MUSIC, false);

//Insert it into the database
this.getContentResolver().insert(MediaStore.Audio.Media.getContentUriForPath(k.getAbsolutePath()), values);

Ratings, reviews, feedback and feature requests are most welcome.

Download Link

Android Market Link (For android phones)

Below are some code snippets for sending messages to twitter from your application by utilizing a twitter application.

The following code will create a new intent(a request to android for something to happen) for the twidroid application and pass it the message we wish to send. It is important to set the type of the intent as it will fail without it (from at least android 1.5). It will then start the activity and we use a try/catch encase twidroid is not found.

	Intent intent = new Intent("com.twidroid.SendTweet");
	intent.putExtra("com.twidroid.extra.MESSAGE",
	"@stealthcopter Example tweet from android application");
	intent.setType("application/twitter");
	try {
		startActivity(intent);
	}
	catch (ActivityNotFoundException e) {
		/* Handle Exception if Twidroid is not installed */
		Toast.makeText(this, "Twidroid not found.", Toast.LENGTH_SHORT).show();
	}

But what if someone has a different twitter application installed? this can be solved by offering the user a choice of application to open.

	Intent intent = new Intent(Intent.ACTION_SEND);
	intent.putExtra(Intent.EXTRA_TEXT,
	"@stealthcopter Example tweet from android application");
	intent.setType("application/twitter");
	try {
		startActivity(Intent.createChooser(intent, null));
	}
	catch (ActivityNotFoundException e) {
		/* Handle Exception if no suitable apps installed */
		Toast.makeText(this, "No suitable apps found.", Toast.LENGTH_SHORT).show();
	}

By combining these two solutions we can make the choice dialog only pop up if the system cannot find the twidroid application. This can be then taken even further by asking the user if they wish to visit the market place to install a twitter application if none is found.

   new AlertDialog.Builder(WordCube.this)
   .setTitle("Get Twitter")
   .setMessage("No twitter Application not found. Goto market and install one now?")
   .setIcon(R.drawable.logo)
   .setNegativeButton(R.string.dialog_no, null)
                   .setPositiveButton(R.string.dialog_yes, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int whichButton) {
                	intentMarket("market://search?q=twitter");
                }
            })
   .show();

Where intentMarket() is defined a to open up the market and search for the specified application passed to it as a string.

public void intentMarket(String url){
	Intent i = new Intent(Intent.ACTION_VIEW);
	Uri u = Uri.parse(url);
	i.setData(u);
	try {
		startActivity(i);
	} catch (ActivityNotFoundException e) {
		toastMessage("Market not found.");
	}
}

Below shows two screenshots from the wordcube application. This application is avaliable for android, see here for more information and download link (or visit market on your android device).

Update: This is now taken into a complete function in this post.

Android is a brilliant smart phone operating system, this is the start of a short series of guides for starting to program applications for it using the android SDK.

Android SDK
Download the android SDK

Once downloaded untar the SDK

tar xvzf android-sdk_r04-linux_86.tgz

The SDK is not complete as additional files need to be downloaded in order to compile for different versions of android. Open the SDK and AVG management application by moving into the SDK folder and running the following.

sh tools/android

In the avaliable packages select the android versions you wish to develop for, and begin downloading them. Should this fail please read the next section, otherwise skip ahead.

Failing to download
If you cannot download from the google website, goto settings and select “force https://… source to be fetched using http://” and click save and apply.

If this still does not work (as was the case for me) it is possible that for some reason a configuration file was not created for this program, this can be solved by creating it manually:

echo sdkman.force.http=true > ~/.android/androidtool.cfg

Creating Android Virtual Devices
You can create virtual android phones using the SDK and AVD manager, click the Virtual Device tab and select new. Enter a name for the device, and a size for the sd card and simply click create AVD.

Once you’ve created you Virtual Device(s) it should look like the following:

You can test these virtual devices and see how nicely the phones are emulated. This is much more useful once you begin writing applications.

Eclipse

I would highly recommend using eclipse as it, along with the android plugin, greatly simplifies production and testing of applications.

Download eclipse from the ubuntu repositories (or from the eclipse website)

sudo apt-get install eclipse

If you do not already have java installed then you will need to install it.

sudo apt-get install sun-java6-jdk sun-java6-jre

You will need to add the following line to your .bashrc in your home folder so that the android tools can be used in eclipse (and other programs).

export PATH=${PATH}:/home/user/android/sdk/tools

* replace /home/user/android/sdk with the path to where you downloaded the SDK

Installing the android plugin for eclipse
Google’s eclipse plugin install guide.

In eclipse goto help then Install new software and then add the google plugin url

https://dl-ssl.google.com/android/eclipse/

Then install Android DDMS and Android Development Tools.

Should you receive errors (like I did) relating to a missing package you will need to add the eclipse repository and install the missing packages.

http://download.eclipse.org/releases/galileo

You should then have a fully working eclipse with android plugin.

What next?
Now you should have everything setup in order to develop and android applications. I would recommend the google tutorials:

• Hello World
• Notepad