将许多滤色镜应用于同一个可绘制的

Question

我想在链中应用几个彩色滤镜到drawable.那可能吗？或者也许创建一个过滤器,它是我想要应用的过滤器的组合.

例如,我想:

Drawable d = ...;
d.setColorFilter(0x3F000000, Mode.OVERLAY).setColorFilter(0xFF2D2D2D, Mode.SCREEN)

Answer 1

这是我最终使用的方法:Drawable在a上操作位图Canvas并根据需要应用尽可能多的图层,使用Paint它不仅适用于彩色滤镜,还适用于任何类型的图像混合.

...
Drawable myBackground = createBackground(getResources().getColor(R.color.Green)); 
setBackgroundDrawable(myBackground);
...

private Drawable createBackground(int color) {

    Canvas canvas = new Canvas();
    Bitmap buttonImage = BitmapFactory.decodeResource(getResources(), R.drawable.btn_image);
    Bitmap buttonShadows = BitmapFactory.decodeResource(getResources(), R.drawable.btn_shadows);
    Bitmap buttonHighLights = BitmapFactory.decodeResource(getResources(), R.drawable.btn_highlights);
    Bitmap result = Bitmap.createBitmap(buttonImage.getWidth(), buttonImage.getHeight(), Bitmap.Config.ARGB_8888);

    canvas.setBitmap(result);
    Paint paint = new Paint();
    paint.setFilterBitmap(false);

    // Color
    paint.setColorFilter(new PorterDuffColorFilter(color, Mode.MULTIPLY));
    canvas.drawBitmap(buttonImage, 0, 0, paint);
    paint.setColorFilter(null);
    // Shadows
    paint.setXfermode(new PorterDuffXfermode(Mode.MULTIPLY));
    canvas.drawBitmap(buttonShadows, 0, 0, paint);
    // HighLights
    paint.setXfermode(new PorterDuffXfermode(Mode.SCREEN));
    canvas.drawBitmap(buttonHighLights, 0, 0, paint);

    paint.setXfermode(null);
    return new BitmapDrawable(getResources(), result);
}

警告: setBackgroundDrawable(Drawable d)已被弃用,虽然setBackground(Drawable d)只能从api 16开始使用,所以如果你有像我这样的最小目标api-14最大目标api-17你没有"干净"的方式将drawable设置为背景.我坚持不推荐的电话.