Android绘制圆角图片

public class PhotoTestActivity extends Activity {

    /** Called when the activity is first created. */

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);

        ImageView image = (ImageView)findViewById(R.id.image);

        Bitmap photo = BitmapFactory.decodeResource(getResources(), R.drawable.test);

        image.setImageBitmap(createFramedPhoto(500,400,photo,50));

    }

 

 

    /**

     *

     * @param x 图像的宽度

     * @param y 图像的高度

     * @param image 源图片

     * @param outerRadiusRat 圆角的大小

     * @return 圆角图片

     */

    Bitmap createFramedPhoto(int x, int y, Bitmap image, float outerRadiusRat) {

        //根据源文件新建一个darwable对象

        Drawable imageDrawable = new BitmapDrawable(image);

 

 

        // 新建一个新的输出图片

        Bitmap output = Bitmap.createBitmap(x, y, Bitmap.Config.ARGB_8888);

        Canvas canvas = new Canvas(output);

 

 

        // 新建一个矩形

        RectF outerRect = new RectF(0, 0, x, y);

 

 

        // 产生一个红色的圆角矩形

        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);

        paint.setColor(Color.RED);

        canvas.drawRoundRect(outerRect, outerRadiusRat, outerRadiusRat, paint);

 

 

        // 将源图片绘制到这个圆角矩形上

        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

        imageDrawable.setBounds(0, 0, x, y);

        canvas.saveLayer(outerRect, paint, Canvas.ALL_SAVE_FLAG);

        imageDrawable.draw(canvas);

        canvas.restore();

 

 

        return output;

    }

}