CircleTransform.java 文件源码

public Bitmap transform(Bitmap source) {
    int size = Math.min(source.getWidth(), source.getHeight());
    Bitmap squaredBitmap = Bitmap.createBitmap(source, (source.getWidth() - size) / 2, (source.getHeight() - size) / 2, size, size);
    if (squaredBitmap != source) {
        source.recycle();
    }
    Bitmap bitmap = Bitmap.createBitmap(size, size, source.getConfig());
    Canvas canvas = new Canvas(bitmap);
    Paint paint = new Paint();
    paint.setShader(new BitmapShader(squaredBitmap, TileMode.CLAMP, TileMode.CLAMP));
    paint.setAntiAlias(true);
    float r = ((float) size) / 2.0f;
    canvas.drawCircle(r, r, r, paint);
    squaredBitmap.recycle();
    return bitmap;
}