CircleTransform.java 文件源码

@Override
protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) {
    if (toTransform == null) return null;

    int size = Math.min(toTransform.getWidth(), toTransform.getHeight());
    int x = (toTransform.getWidth() - size) / 2;
    int y = (toTransform.getHeight() - size) / 2;

    Bitmap squared = Bitmap.createBitmap(toTransform, x, y, size, size);

    Bitmap result = pool.get(size, size, Bitmap.Config.ARGB_8888);
    if (result == null) {
        result = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
    }

    Canvas canvas = new Canvas(result);
    Paint paint = new Paint();
    paint.setShader(new BitmapShader(squared, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP));
    paint.setAntiAlias(true);
    float r = size / 2f;
    canvas.drawCircle(r, r, r, paint);
    return result;
}