自定义带圆角的ImageView

      最近有一个实现一个带有圆角的ImageView的需求,在网上找了找三方,虽然Demo都是正确的,但是移植过来就不可以了,因为请求链接的时候用的是xUtils中Bitmap来进行解析的,这样就总是会报类型转换异常的错误.

就这样只能自己定义一个了.

Demo:

package com.yizooo.yizooo.ui;


import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.RectF;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.ImageView;

import com.lidroid.xutils.bitmap.core.AsyncDrawable;


/**
 * Created by 雪宝宝 on 2016/3/27.
 * 自定义圆角工具
 */
public class RoundImageView extends ImageView {
    private Paint paint;

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

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

    public RoundImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        paint  = new Paint();
    }

    /**
     * 绘制圆角矩形图片
     */
    @Override
    protected void onDraw(Canvas canvas) {
        Drawable drawable = getDrawable();
        Bitmap bitmap = null;
        if (null != drawable && drawable instanceof  BitmapDrawable ) {
            BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
             bitmap  = bitmapDrawable.getBitmap();
            //Bitmap bitmap =( (BitmapDrawable)drawable).getBitmap();
            Bitmap b = getRoundBitmap(bitmap, 10);
            final Rect rectSrc = new Rect(0, 0, b.getWidth(), b.getHeight());
            final Rect rectDest = new Rect(0,0,getWidth(),getHeight());
            paint.reset();
            canvas.drawBitmap(b, rectSrc, rectDest, paint);

        }//防止出现类型转换异常
        else if(this.getDrawable() instanceof AsyncDrawable){
            bitmap = Bitmap
                    .createBitmap(
                            getWidth(),
                            getHeight(),
                            drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                                    : Bitmap.Config.RGB_565);
            Canvas canvas1 = new Canvas(bitmap);
            // canvas.setBitmap(bitmap);
            drawable.setBounds(0, 0, getWidth(),
                    getHeight());
            drawable.draw(canvas1);
        }
        else {
            super.onDraw(canvas);
        }
    }

    /**
     * 获取圆角矩形图片方法
     * @param bitmap
     * @param roundPx,一般设置成14
     * @return Bitmap
     * @author caizhiming
     */
    private Bitmap getRoundBitmap(Bitmap bitmap, int roundPx) {
        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
                bitmap.getHeight(), Config.ARGB_8888);
        Canvas canvas = new Canvas(output);

        final int color = 0xff424242;

        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
        final RectF rectF = new RectF(rect);
        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);
        paint.setColor(color);
        int x = bitmap.getWidth();

        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        return output;


    }
}

        最终的效果图就不发照片了,各位朋友尝试一下就可以看出效果图了.