仿支付宝头像外加一个边框的工具类

代码：

/**
     * 获取圆角矩形或圆形图片的方法
     *
     * @param bitmap 待处理 bitmap 对象
     * @param pixels 圆角半径，x 和 y 相等
     * @return 返回圆角或者圆形 bitmap
     */
    public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int pixels) {
        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(output);

        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
        final RectF rectF = new RectF(rect);
        final float roundPx = pixels;

        paint.setAntiAlias(true);
        //柱：一定要先画圆角矩形
        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        return output;
    }

    /**
     * 获取待边框的圆角矩形或圆形图片方法
     *
     * @param resources          {@link Resources}
     * @param resId              对应资源 id
     * @param borderCornerRadius 边框圆角半径，x 和 y 相等
     * @return 圆角矩形或圆形 bitmap 对象
     */
    public static Bitmap getRoundCornerBitmapWithBorder(Resources resources, int resId, int borderCornerRadius) {
        Bitmap src = BitmapFactory.decodeResource(resources, resId);
        Bitmap temp_out = getRoundedCornerBitmap(src, 0);//图片默认为矩形的
        Bitmap out = Bitmap.createBitmap(temp_out.getWidth(), temp_out.getHeight(), Bitmap.Config.ARGB_8888);
        //新建画布
        Canvas canvas = new Canvas(out);
        //原始大小的矩形
        Rect rect = new Rect(0, 0, temp_out.getWidth(), temp_out.getHeight());
        //矩形宽高的两边都缩小 10
        Rect insetRect = new Rect(rect);
        //外面白色变宽宽度 默认为 10
        final int borderWidth = 8;
        //缩小矩形
        insetRect.inset(borderWidth, borderWidth);

        Paint paint = new Paint();
        //把图像信息画在缩小后的矩形区域内
        canvas.drawBitmap(temp_out, rect, insetRect, paint);

        paint.setAntiAlias(true);
        paint.setColor(0xFFCE3D3A);
        paint.setStyle(Paint.Style.STROKE);
        paint.setStrokeWidth(borderWidth);
        //画边框线
        canvas.drawRoundRect(new RectF(insetRect), borderCornerRadius, borderCornerRadius, paint);
        return out;
    }

注：getRoundedCornerBitmap() 方法中一定要先画圆角矩形，原因可以看一下上篇文章：

安卓 Paint 的 Xfermode

调用：

iv.setImageBitmap(BitmapHelper.getRoundCornerBitmapWithBorder(getResources(), R.mipmap.icon_avater, 14));

效果：