gistfile1.java

  @Override
	public void onDreamingStarted() {
		super.onDreamingStarted();

		galaxy = (ImageView) findViewById(R.id.galaxyView);

		mHandler.postDelayed(pictureChange, PICTURE_CHANGE_TIME);
		int rndInt = rand.nextInt(PICTURE_RAND_NUM);
		
		int imgId = imageResIds[rndInt];
		
		String imgName = Integer.toString(imgId);

		galaxy.setImageDrawable(getResources().getDrawable(imgId));
	}

	private Runnable pictureChange = new Runnable() {

		@Override
		public void run() {

			int rndInt = rand.nextInt(PICTURE_RAND_NUM) + 1;
			int imgId = imageResIds[rndInt];
			String imgName = Integer.toString(imgId);

			Drawable[] ids = { galaxy.getDrawable(), getResources().getDrawable(imgId) };
			TransitionDrawable mTransition = new TransitionDrawable(ids);
			mTransition.setCrossFadeEnabled(true);
			mTransition.startTransition(5000);

			galaxy.setImageDrawable(mTransition);
			mHandler.postDelayed(this, PICTURE_CHANGE_TIME);

		}
	};