ACache.java 文件源码

private static Bitmap drawable2Bitmap(Drawable drawable) {
    if (drawable == null) {
        return null;
    }
    // 取 drawable 的长宽
    int w = drawable.getIntrinsicWidth();
    int h = drawable.getIntrinsicHeight();
    // 取 drawable 的颜色格式
    Bitmap.Config config = drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
            : Bitmap.Config.RGB_565;
    // 建立对应 bitmap
    Bitmap bitmap = Bitmap.createBitmap(w, h, config);
    // 建立对应 bitmap 的画布
    Canvas canvas = new Canvas(bitmap);
    drawable.setBounds(0, 0, w, h);
    // 把 drawable 内容画到画布中
    drawable.draw(canvas);
    return bitmap;
}