Android圆形头像显示自定义View

在项目开发中，需要给用户的头像设置为圆形。无论获取到什么图片，都显示为圆形头像。自定义View写法如下。使用的时候在XML布局中，直接使用就好。

public class MyCircleImageView extends ImageView{    private int mBorderThickness = 0;    private Context mContext;    private int defaultColor = 0xFFFFFFFF;    // 如果只有其中一个有值，则只画一个圆形边框    private int mBorderOutsideColor = 0;    private int mBorderInsideColor = 0;    // 控件默认长、宽    private int defaultWidth = 0;    private int defaultHeight = 0;    public MyCircleImageView(Context context) {        super(context);        mContext = context;    }    public MyCircleImageView(Context context, AttributeSet attrs) {        super(context, attrs);        mContext = context;        setCustomAttributes(attrs);    }    public MyCircleImageView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        mContext = context;        setCustomAttributes(attrs);    }    private void setCustomAttributes(AttributeSet attrs) {        TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.roundedimageview);        mBorderThickness = a.getDimensionPixelSize(R.styleable.roundedimageview_border_thickness, 0);        mBorderOutsideColor = a.getColor(R.styleable.roundedimageview_border_outside_color,defaultColor);        mBorderInsideColor = a.getColor(R.styleable.roundedimageview_border_inside_color, defaultColor);    }    @Override    protected void onDraw(Canvas canvas) {        Drawable drawable = getDrawable() ;        if (drawable == null) {            return;        }        if (getWidth() == 0 || getHeight() == 0) {            return;        }        this.measure(0, 0);        if (drawable.getClass() == NinePatchDrawable.class)            return;        Bitmap b = ((BitmapDrawable) drawable).getBitmap();        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);        if (defaultWidth == 0) {            defaultWidth = getWidth();        }        if (defaultHeight == 0) {            defaultHeight = getHeight();        }        int radius = 0;        if (mBorderInsideColor != defaultColor && mBorderOutsideColor != defaultColor) {// 定义画两个边框，分别为外圆边框和内圆边框            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - 2 * mBorderThickness;            // 画内圆            drawCircleBorder(canvas, radius + mBorderThickness / 2,mBorderInsideColor);            // 画外圆            drawCircleBorder(canvas, radius + mBorderThickness + mBorderThickness / 2, mBorderOutsideColor);        } else if (mBorderInsideColor != defaultColor && mBorderOutsideColor == defaultColor) {// 定义画一个边框            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness;            drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderInsideColor);        } else if (mBorderInsideColor == defaultColor && mBorderOutsideColor != defaultColor) {// 定义画一个边框            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness;            drawCircleBorder(canvas, radius + mBorderThickness / 2, mBorderOutsideColor);        } else {// 没有边框            radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2;        }        Bitmap roundBitmap = getCroppedRoundBitmap(bitmap, radius);        canvas.drawBitmap(roundBitmap, defaultWidth / 2 - radius, defaultHeight / 2 - radius, null);    }    /**     * 获取裁剪后的圆形图片     * @param //radius半径     */    public Bitmap getCroppedRoundBitmap(Bitmap bmp, int radius) {        Bitmap scaledSrcBmp;        int diameter = radius * 2;        // 为了防止宽高不相等，造成圆形图片变形，因此截取长方形中处于中间位置最大的正方形图片        int bmpWidth = bmp.getWidth();        int bmpHeight = bmp.getHeight();        int squareWidth = 0, squareHeight = 0;        int x = 0, y = 0;        Bitmap squareBitmap;        if (bmpHeight > bmpWidth) {// 高大于宽            squareWidth = squareHeight = bmpWidth;            x = 0;            y = (bmpHeight - bmpWidth) / 2;            // 截取正方形图片            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth, squareHeight);        } else if (bmpHeight < bmpWidth) {// 宽大于高            squareWidth = squareHeight = bmpHeight;            x = (bmpWidth - bmpHeight) / 2;            y = 0;            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,squareHeight);        } else {            squareBitmap = bmp;        }        if (squareBitmap.getWidth() != diameter || squareBitmap.getHeight() != diameter) {            scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter,diameter, true);        } else {            scaledSrcBmp = squareBitmap;        }        Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),                scaledSrcBmp.getHeight(),                Bitmap.Config.ARGB_8888);        Canvas canvas = new Canvas(output);        Paint paint = new Paint();        Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(),scaledSrcBmp.getHeight());        paint.setAntiAlias(true);        paint.setFilterBitmap(true);        paint.setDither(true);        canvas.drawARGB(0, 0, 0, 0);        canvas.drawCircle(scaledSrcBmp.getWidth() / 2,                scaledSrcBmp.getHeight() / 2,                scaledSrcBmp.getWidth() / 2,                paint);        paint.setXfermode(new PorterDuffXfermode( PorterDuff.Mode.SRC_IN));        canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);        bmp = null;        squareBitmap = null;        scaledSrcBmp = null;        return output;    }    /**     * 边缘画圆     */    private void drawCircleBorder(Canvas canvas, int radius, int color) {        Paint paint = new Paint();            /* 去锯齿 */        paint.setAntiAlias(true);        paint.setFilterBitmap(true);        paint.setDither(true);        paint.setColor(color);            /* 设置paint的　style　为STROKE：空心 */        paint.setStyle(Paint.Style.STROKE);            /* 设置paint的外框宽度 */        paint.setStrokeWidth(mBorderThickness);        canvas.drawCircle(defaultWidth / 2, defaultHeight / 2, radius, paint);    }}