android ImageView 添加边框

有两种方法可以给ImageView添加边框，一种是通过xml文件配置shape.另一种是重写ImageView的ondraw方法，这里用第二中方法：

package org.example.image.widgets;import android.content.Context;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.Rect;import android.widget.ImageView;public class MyImageView extends ImageView {// 边框颜色private int borderColor;// 边框宽度private int borderWidth;public MyImageView(Context context) {super(context);}// 设置边框颜色public void setBorderColor(int borderColor) {this.borderColor = borderColor;}// 设置边框宽度public void setBorderWidth(int borderWidth) {this.borderWidth = borderWidth;}// 重写绘图方法@Overrideprotected void onDraw(Canvas canvas) {super.onDraw(canvas);// 画边框Rect rect = canvas.getClipBounds();rect.bottom--;rect.right--;Paint paint = new Paint();paint.setColor(borderColor);paint.setStyle(Paint.Style.STROKE);paint.setStrokeWidth(borderWidth);canvas.drawRect(rect, paint);}}