How rebuild only one module in project Android Studio

zipalign [-f] [-v] <alignment> infile.apk outfile.apk

// command line in Total Commander
zipalign.exe -f -v 4 infile.apk outfile.apk

When using Eclipse with the ADT plugin, the Export Wizard will automatically zipalign your .apk after it signs it with your private key.

String s = "Some text for appending

";
 TextView   mTitle = (TextView) findViewById(R.id.title_text);
 mTitle.setText(R.string.app_name); // insert text from strings.xml
 mTitle.append(s); // append string like a variable value
 mTitle.append("My string will appended

"); // append string

import android.content.Context;
import android.media.AudioManager;
import android.media.SoundPool;

public class SoundManager
{
  private SoundPool soundPool;
  private int[] sm;
  Context context;

  public SoundManager(Context context) {
    this.context = context;
    soundPool = new SoundPool(4, AudioManager.STREAM_MUSIC, 0);
    sm = new int[2];
    // fill your sounds
    sm[0] = soundPool.load(context, R.raw.my_sound1, 1);
    sm[1] = soundPool.load(context, R.raw.my_sound2, 1);
  }

  public final void playSound(int sound) {
      AudioManager mgr = (AudioManager)context.getSystemService(
          Context.AUDIO_SERVICE);  
      float streamVolumeCurrent =
          mgr.getStreamVolume(AudioManager.STREAM_MUSIC);
      float streamVolumeMax = mgr.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
      float volume = streamVolumeCurrent / streamVolumeMax;
      soundPool.play(sm[sound], volume, volume, 1, 0, 1f);
  }

  public final void cleanUpIfEnd() {
    sm = null;
    context = null;
    soundPool.release();
    soundPool = null;
  }
}

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        final AssetManager assetManager = getAssets();
        try {
			// for assets folder add empty string
                        String[] filelist = assetManager.list("");
                        // for assets/subFolderInAssets add only subfolder name
                        String[] filelistInSubfolder = assetManager.list("subFolderInAssets");
			if (filelist == null) {
			    // dir does not exist or is not a directory
			} else {
			    for (int i=0; i<filelist.length; i++) {
			        // Get filename of file or directory
			        String filename = filelist[i];
			    }
			}
                     
                        // if(filelistInSubfolder == null) ............  

		} catch (IOException e) {
			e.printStackTrace();
		}
     }

// image from res/drawable
	int resID = getResources().getIdentifier("my_image", 
			"drawable", getPackageName());
// view
	int resID = getResources().getIdentifier("my_resource", 
			"id", getPackageName());

// string
	int resID = getResources().getIdentifier("my_string", 
			"string", getPackageName());