A simple class that makes a view blink, without the need of Thread or Timer objects. The rest is self explanatory.

gistfile1.java

import android.content.Context;
import android.graphics.drawable.AnimationDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.ImageView;

/**
 * 
 * @author Andaluz
 * It's free like freedom, but with respect to each other :)'
 */
public class BlinkImageView extends ImageView {
	private final String TAG = "BlinkImageView";
	
	private AnimationDrawable mAniFrame;
	private boolean isFirstTime;
	private int timeOn;
	private int timeOff;
	private int resourceOn;
	private int resourceOff;

	public BlinkImageView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		
		isFirstTime = true;
		timeOn = 500;
		timeOff = 500;
		resourceOn = -1;
		resourceOff = -1;
	}

	public BlinkImageView(Context context, AttributeSet attrs) {
		super(context, attrs);
		
		isFirstTime = true;
		timeOn = 500;
		timeOff = 500;
		resourceOn = -1;
		resourceOff = -1;
	}

	public BlinkImageView(Context context) {
		super(context);
		
		isFirstTime = true;
		timeOn = 500;
		timeOff = 500;
		resourceOn = -1;
		resourceOff = -1;
	}

	public void setResources(int off, int on) {
		resourceOff = off;
		resourceOn = on;
		
	}
	
	public void setDurationTime(int off, int on) {
		if (off != 0)
			timeOff = off;
		
		if(on!=0)
			timeOn = on;
	}
	
	public void doBlink() {
		if(isFirstTime) {
			initializeAnimationDrawable();
			isFirstTime = false;
		} else
			mAniFrame.setVisible(false, true); // <-- a little hack, this will reset the animation.
		
		mAniFrame.start();
	}
	
	private void initializeAnimationDrawable() {
		mAniFrame = new AnimationDrawable();
		mAniFrame.setOneShot(true);
		
		mAniFrame.addFrame(getResources().getDrawable(resourceOn), timeOn);
		mAniFrame.addFrame(getResources().getDrawable(resourceOff), timeOff);
		
		setBackgroundDrawable((Drawable)mAniFrame);
	}
}