How to apply a color filter to a view with all children

Question

How do I grey out a view uniformly which contains many different items - ImageViews, TextViews, background image. Do I have to grey out each thing individually? Or is there

Answer 1

Sam Lu's answer is a good start, but I had performance problems and decided to switch to hardware layers. With hardware layers, you can do it like this:

private final Paint grayscalePaint = new Paint();

ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);        
grayscalePaint.setColorFilter(new ColorMatrixColorFilter(cm));

public void setGrayedOut(boolean grayedOut) {       
    if (grayedOut) {
        setLayerType(View.LAYER_TYPE_HARDWARE, grayscalePaint);
    } else {
        setLayerType(View.LAYER_TYPE_NONE, null);       
    }       
}

Be careful not to do the layers in dispatchDraw() itself as that will crash the app.