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package com.example.administrator.testt;import android.content.Context;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.PaintFlagsDrawFilter;import android.graphics.Path;import android.graphics.Rect;import android.graphics.Region;import android.util.AttributeSet;public class RoundImageView extends android.support.v7.widget.AppCompatImageView{    private Bitmap mBitmap;    private Rect mRect = new Rect();//Rect=Rectangle    private PaintFlagsDrawFilter pdf = new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG);    private Paint mPaint = new Paint();    private Path mPath = new Path();    public RoundImageView(Context context, AttributeSet attributeSet) {        super(context,attributeSet);        init();    }    public void setBitmap(Bitmap bitmap) {        this.mBitmap = bitmap;    }    private void init(){        mPaint.setStyle(Paint.Style.STROKE);        mPaint.setFlags(Paint.ANTI_ALIAS_FLAG);        mPaint.setAntiAlias(true); // 抗锯齿    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        if (mBitmap == null) {            return;        }        mRect.set(0, 0, getWidth(), getHeight());        canvas.save();        canvas.setDrawFilter(pdf);        mPath.addCircle(getWidth()/2,getWidth()/2,getHeight()/2,Path.Direction.CCW);        canvas.clipPath(mPath, Region.Op.REPLACE);        canvas.drawBitmap(mBitmap, null, mRect, mPaint);//绘制图        canvas.restore();    }}