How to make an image transparent android

Question

Think I have an bitmap that I have loaded it from Album Art in Media Store , It has 100 percent transparent value , how can I change that to 50 or 30 ?

Also Do you know any way that I can make image black and white ?

thanks

Answer 1

Set the alpha between 0 to 255!!

alpha set to 45 will make the image transparent

ViewName.getBackground().setAlpha(65);

Answer 2

Use the following method:

/**
 * @param bitmap The source bitmap.
 * @param opacity a value between 0 (completely transparent) and 255 (completely
 * opaque).
 * @return The opacity-adjusted bitmap.  If the source bitmap is mutable it will be
 * adjusted and returned, otherwise a new bitmap is created.
 */
private Bitmap adjustOpacity(Bitmap bitmap, int opacity)
{
    Bitmap mutableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);
    Canvas canvas = new Canvas(mutableBitmap);
    int colour = (opacity & 0xFF) << 24;
    canvas.drawColor(colour, PorterDuff.Mode.DST_IN);
    return mutableBitmap;
}

Explanation here: http://blog.uncommons.org/2011/01/12/adjusting-the-opacity-of-an-android-bitmap/