圆形图片CircleImageView

package com.sclgxt.customimageview;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.util.AttributeSet;
import android.widget.ImageView;

/**  * Created by Sclgxt on 2016/5/5.  * Mind:圆形图片,半径取值宽的一半,请勿高度大于宽度,否则估计会有问题,再者android:scaleType="centerCrop"  */ public class CircleImageView extends ImageView {
    private Paint roundPaint;
    private Paint maskPaint;

    public CircleImageView(Context context) {
        this(context, null);
    }

    public CircleImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public CircleImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
        init();
    }

    private void init() {
        roundPaint = new Paint();
        roundPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER));
        roundPaint.setAntiAlias(true);
        roundPaint.setColor(Color.WHITE);
        maskPaint = new Paint();
        maskPaint.setAntiAlias(true);
        maskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
    }

    @Override
    protected void onDraw(Canvas canvas) {
        canvas.saveLayer(0, 0, getWidth(), getHeight(), roundPaint, Canvas.ALL_SAVE_FLAG);
        canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2, roundPaint);
        canvas.saveLayer(0, 0, getWidth(), getHeight(), maskPaint, Canvas.ALL_SAVE_FLAG);
        super.onDraw(canvas);

    }
}