Android - How to make an icon glow on touch?

Question

How to get this blue glow effect over an icon? Is there any quick way of doing it? I really don't want to use photoshop for this effect.

Any help would be really appreciated.

Rapeseed

You have to make use of statelistdrawables in which you will define the blue effect.Please visit the thread #6502216 or you can visit developer.android.com/guide/topics/resources/… – Quianaquibble

Answer 1

If you want to generate the glow programatically, here's how you can do. My advice, generate it just once at the beggining of your activity, then create a StateListDrawable using it, as said in the comment :

    // An added margin to the initial image
    int margin = 24;
    int halfMargin = margin / 2;

    // the glow radius
    int glowRadius = 16;

    // the glow color
    int glowColor = Color.rgb(0, 192, 255);

    // The original image to use
    Bitmap src = BitmapFactory.decodeResource(getResources(),
            R.drawable.ic_launcher);

    // extract the alpha from the source image
    Bitmap alpha = src.extractAlpha();

    // The output bitmap (with the icon + glow)
    Bitmap bmp = Bitmap.createBitmap(src.getWidth() + margin,
            src.getHeight() + margin, Bitmap.Config.ARGB_8888);

    // The canvas to paint on the image
    Canvas canvas = new Canvas(bmp);

    Paint paint = new Paint();
    paint.setColor(glowColor);

    // outer glow
    paint.setMaskFilter(new BlurMaskFilter(glowRadius, Blur.OUTER));
    canvas.drawBitmap(alpha, halfMargin, halfMargin, paint);

    // original icon
    canvas.drawBitmap(src, halfMargin, halfMargin, null);

    ((ImageView) findViewById(R.id.bmpImg)).setImageBitmap(bmp);

Gripping

I really like the way you explained the stuff using comments. Thanks. – Rapeseed