在圆形位图上添加圆框圆

Question

我试图在我的位图周围创建一个圆形框架!

使用此代码,我可以使我的位图圆形:

    public static Bitmap getRoundedCornerBitmap(Bitmap bitmap) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap
            .getHeight(), Config.ARGB_8888);
    Canvas canvas = new Canvas(output);

    final int color = 0xff4242DB;
    final Paint paint = new Paint();
    final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
    final RectF rectF = new RectF(rect);
    final float roundPx = bitmap.getWidth()/2;

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    paint.setColor(color);
    canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

    paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        //canvas.drawCircle(0, 0, bitmap.getWidth(), paint);
    canvas.drawBitmap(bitmap, rect, rect, paint);

    return output;
}

我试过的是用画布绘制一个圆圈(outcommented line),但它没有结果.有谁知道如何在它周围添加圆形边框？

编辑

当我使用该行时:

canvas.drawCircle(0, 0, bitmap.getWidth(), paint);

效果是,3个角落圆润,但左上角保持不变(90度),但我看不到任何线条或圆圈!

Answer 1

更新

现在有RoundedBitmapDrawable,并在相应的工厂支持库,我建议使用,除非需要更多的灵活性.

原始答案

您必须在位图后绘制圆圈.这就是我的诀窍.

int w = bitmap.getWidth();                                          
int h = bitmap.getHeight();                                         

int radius = Math.min(h / 2, w / 2);                                
Bitmap output = Bitmap.createBitmap(w + 8, h + 8, Config.ARGB_8888);

Paint p = new Paint();                                              
p.setAntiAlias(true);                                               

Canvas c = new Canvas(output);                                      
c.drawARGB(0, 0, 0, 0);                                             
p.setStyle(Style.FILL);                                             

c.drawCircle((w / 2) + 4, (h / 2) + 4, radius, p);                  

p.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));                 

c.drawBitmap(bitmap, 4, 4, p);                                      
p.setXfermode(null);                                                
p.setStyle(Style.STROKE);                                           
p.setColor(Color.WHITE);                                            
p.setStrokeWidth(3);                                                
c.drawCircle((w / 2) + 4, (h / 2) + 4, radius, p);                  

return output;   

这当然不包括你的例子的幻想阴影.您可能想要使用额外的像素来玩一点点.