android裁剪圆形几种方式.

  fun circleBitmap(bitmap: Bitmap):Bitmap{
        var bitmapCircle=Bitmap.createBitmap(100,100,Bitmap.Config.ARGB_8888)
        var canvas=Canvas(bitmapCircle)
        var paint=Paint()
        paint.isAntiAlias=true
      //  使用Shader着色器 画
    
      //使用Xfermode图像混合模式
        canvas.drawCircle(50f,50f,40f,paint)
        paint.setXfermode(PorterDuffXfermode(PorterDuff.Mode.SRC_IN))
        canvas.drawBitmap(bitmap,0f,0f,paint) 

       

        paint.reset()
        paint.setAntiAlias(true);
        paint.setFilterBitmap(true);
        paint.setDither(true);
        paint.setColor(Color.RED);
        paint.setStyle(Paint.Style.STROKE);
        paint.setStrokeWidth(3f);
        canvas.drawCircle(50f, 50f, 40f, paint);
        return bitmapCircle;