ImageView - ColorFilter

Question

I have an ImageView and use a ColorFilter (PorterDuff.Mode.MULTIPLY).

Is it possible to use this colorFilter but not on the whole image? It must be like a 'margin' / 'padding'.

Example: The image width and height = 100dp. But the colorFilter must be 50dp (width and height) on the center of the ImageView.

The picture below is what I need (red = colorFilter)

Answer 1

You can subclass ImageView and override its onDraw() method. I am posting a minimalictic solution, modify to your needs!

public class OverlayImageView extends ImageView {
    Paint paint;
    float padding = 30;

    public OverlayImageView(Context context) {
        super(context);
        init();
    }

    public OverlayImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public OverlayImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        paint = new Paint();
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.MULTIPLY));
        paint.setColor(Color.RED);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        canvas.drawRect(padding, padding, canvas.getWidth()-padding, canvas.getHeight()-padding, paint);
    }
}