<SPAN xmlns="http://www.w3.org/1999/xhtml">package yan.guoqi.rectphoto; import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Paint.Style; import android.graphics.RectF; import android.util.AttributeSet; import android.widget.ImageView; public class DrawImageView extends ImageView {  private final Paint paint;  private final Context context;   public DrawImageView(Context context, AttributeSet attrs) {   super(context, attrs);   // TODO Auto-generated constructor stub   this.context = context;   this.paint = new Paint();   this.paint.setAntiAlias(true); //消除锯齿                 this.paint.setStyle(Style.STROKE);  //绘制空心圆或 空心矩形               }         @Override  protected void onDraw(Canvas canvas) {   // TODO Auto-generated method stub   int center = getWidth()/2;   int innerCircle = dip2px(context, 83); //内圆半径   int ringWidth = dip2px(context, 10);   //圆环宽度   // 第一种方法绘制圆环   //绘制内圆                 this.paint.setARGB(255, 138, 43, 226);   this.paint.setStrokeWidth(2);   canvas.drawCircle(center, center, innerCircle, this.paint);                    //绘制圆环                this.paint.setARGB(255, 138, 43, 226);   this.paint.setStrokeWidth(ringWidth);   canvas.drawCircle(center, center, innerCircle + 1 +ringWidth/2, this.paint);                   //绘制外圆    this.paint.setARGB(255, 138, 43, 226);   this.paint.setStrokeWidth(2);   canvas.drawCircle(center, center, innerCircle + ringWidth, this.paint);                     super.onDraw(canvas);  }  /* 根据手机的分辨率从 dp 的单位 转成为 px(像素) */   public static int dip2px(Context context, float dpValue) {    final float scale = context.getResources().getDisplayMetrics().density;    return (int) (dpValue * scale + 0.5f);   }  } </SPAN>