Android实现圆形Imageview，带白色边框

最近做了个UI效果，要求头像是圆形的，外面有白色边框

有需要的同学可以看看，效果如下

 

 

附上实现代码

RoundImageView：

public class RoundImageView extends ImageView {



    public RoundImageView(Context context, AttributeSet attrs) {

        super(context, attrs);

        init();

    }



    public RoundImageView(Context context) {

        super(context);

        init();

    }



    private final RectF roundRect = new RectF();

    private float rect_adius = 90;

    private final Paint maskPaint = new Paint();

    private final Paint zonePaint = new Paint();



    private void init() {

        maskPaint.setAntiAlias(true);

        maskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

        maskPaint.setFilterBitmap(true);

        zonePaint.setAntiAlias(true);

        zonePaint.setColor(Color.WHITE);

        zonePaint.setFilterBitmap(true);

        float density = getResources().getDisplayMetrics().density;

        rect_adius = rect_adius * density;

    }



    public void setRectAdius(float adius) {

        rect_adius = adius;

        invalidate();

    }



    @Override

    protected void onLayout(boolean changed, int left, int top, int right,

            int bottom) {

        super.onLayout(changed, left, top, right, bottom);

        int w = getWidth();

        int h = getHeight();

        roundRect.set(0, 0, w, h);

    }



    @Override

    public void draw(Canvas canvas) {

        canvas.saveLayer(roundRect, zonePaint, Canvas.ALL_SAVE_FLAG);

        canvas.drawRoundRect(roundRect, rect_adius, rect_adius, zonePaint);

        //

        canvas.saveLayer(roundRect, maskPaint, Canvas.ALL_SAVE_FLAG);

        super.draw(canvas);

        canvas.restore();

    }



}

xml文件：

 <RelativeLayout

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:layout_centerVertical="true"

        android:gravity="center_vertical" >



        <com.example.view.RoundImageView

            android:id="@+id/img_user_icon"

            android:layout_width="100dp"

            android:layout_height="100dp"

            android:layout_centerHorizontal="true"

            android:scaleType="centerCrop"

            android:src="@drawable/user_icon" />



        <ImageView

            android:layout_width="100dp"

            android:layout_height="100dp"

            android:layout_centerHorizontal="true"

            android:background="@drawable/usericon_bg_circle" />

    </RelativeLayout>

drawable文件：

usericon_bg_circle.xml

<?xml version="1.0" encoding="UTF-8"?>

<shape xmlns:android="http://schemas.android.com/apk/res/android"

    android:shape="rectangle" >



    <solid android:color="#00000000" />



    <corners android:radius="90dp" />



    <stroke

        android:width="2dp"

        android:color="#fff" />



</shape>