setColorFilter() broken on Android 4, working on Android 5

Question

I am trying to flash different colours onto the screen at regular intervals (a few times per second).

To change the colours, I use Drawable.setColorFilter(int color, Mode mode) on the background of my main view:

• myView.getBackground().setColorFilter(Color.RED, PorterDuff.Mode.SRC);

For debugging purposes, I added another view that I change using View.setBackgroundColor(int color).

The problem is that the setColorFilter() calls are working on Lollipop, but are broken on previous versions (specifically Nexus 7 v4.4.4, Galaxy Nexus v4.2.1).

---

I call the colour changing code inside a Runnable that is triggered at regular intervals by a Handler.

The handler is being called on all platforms (I can see the background changes due to the debugging setBackgroundColor() calls).

Below is the colour cycling code:

Handler mHandler;
RunnableOnTick thisRunnable;
View vDebug;
View vBroken;

class RunnableOnTick implements Runnable
{
    int backgroundColor;

    @Override
    public void run()
    {
        color = random.nextInt(2);

        switch (color)
        {
            case 0:
            {
                backgroundColor = Color.RED;
                break;
            }
            case 1:
            {
                backgroundColor = Color.GREEN;
                break;
            }
        }

        // this works on all platforms
        vDebug.setBackgroundColor(backgroundColor);

        // this works only on Lollipop
        vBroken.getBackground().setColorFilter(backgroundColor, PorterDuff.Mode.SRC);
        vBroken.invalidate();

        mHandler.postDelayed(thisRunnable, 100);
    }
}

---

I have tried different PorterDuff.Mode values - still can't get it working on Android 4.

What is different between Android v4 and v5 that would change the way setColorFilter() works?

Answer 1

I had the same issue on pre-lollipop, I solved replacing:

vBroken.getBackground().setColorFilter(backgroundColor, PorterDuff.Mode.SRC);

with:

    Drawable d = vBroken.getBackground();
    d.setColorFilter(backgroundColor, PorterDuff.Mode.MULTIPLY);
    vBroken.setBackground(d);

Answer 2

Ultimately, it seems like the problem is that KitKat doesn't support using a ColorFilter (or implicitly an alpha) on a Drawable that will in turn be in a StateListDrawable. My solution was to use the same to code to construct the complex Drawable and then render that into a simple BitMapDrawable:

 static Drawable createDrawable(Context context, int color, boolean disabled) {
OvalShape oShape = new OvalShape();
ShapeDrawable background = new ShapeDrawable(oShape);
background.getPaint().setColor(color);

ShapeDrawable shader = new ShapeDrawable(oShape);
shader.setShaderFactory(new ShapeDrawable.ShaderFactory() {
    @Override
    public Shader resize(int width, int height) {
        return new LinearGradient(0, 0, 0, height,
                new int[]{
                        Color.WHITE,
                        Color.GRAY,
                        Color.DKGRAY,
                        Color.BLACK
                }, null, Shader.TileMode.REPEAT);
    }
});

Drawable icon = ContextCompat.getDrawable(context, R.drawable.ic_chat_button).mutate();
icon.setColorFilter(context.getResources().getColor(R.color.control_tint_color), PorterDuff.Mode.SRC_IN);

Drawable layer = new LayerDrawable(new Drawable[]{ shader, background, icon });
layer.setAlpha(disabled ? 128 : 255);

// Note that on KitKat, setting a ColorFilter on a Drawable contained in a StateListDrawable
//  apparently doesn't work, although it does on later versions, so we have to render the colored
//  bitmap into a BitmapDrawable and then put that into the StateListDrawable
Bitmap bitmap = Bitmap.createBitmap(icon.getIntrinsicWidth(), icon.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);

layer.setBounds(0, 0, layer.getIntrinsicWidth(), layer.getIntrinsicHeight());
layer.draw(canvas);

return new BitmapDrawable(context.getResources(), bitmap);
}

Answer 3

There's an issue in AppCompat with compound Drawable below API 21 that me thinks is related: https://code.google.com/p/android/issues/detail?id=191111

The simple solution is not using drawables from XML but create them in code and then apply setColorFilter. That's why @Hardeep solution worked.

Fun trivia: In my case setColorFilter on XML-created TextView drawableLeft worked fine, but only when invoked via click handler / delayed. When invoked in onCreate / onResume etc nothing happened.