本文只寫將圖片變為圓形顯示的處理方法，至於如何呼叫手機相機和相簿拍照裁剪，請看下一篇文章

首先是一個util工具類 ，將此方法放util裡面 直接呼叫

util類：

public class PhotoUtil {
    public Bitmap toRoundBitmap(Bitmap bitmap) {
        int width = bitmap.getWidth();
        int height = bitmap.getHeight();
        float roundPx;
        float left, top, right, bottom, 
 
dst_left, dst_top, dst_right, dst_bottom;
        if (width <= height) {
            roundPx = width / 2;
top = 0;
bottom = width;
left = 0;
right = width;
height = width;
dst_left = 0;
dst_top = 0;
dst_right = width;
dst_bottom = width;
} else {
            roundPx = height / 2;
            float clip = (width - height) / 2
 
;
left = clip;
right = width - clip;
top = 0;
bottom = height;
width = height;
dst_left = 0;
dst_top = 0;
dst_right = height;
dst_bottom = height;
}
        Bitmap output = Bitmap.createBitmap(width,
height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(output);
        final int color = 0xff424242
 
;
        final Paint paint = new Paint();
        final Rect src = new Rect((int) left, (int) top, (int) right, (int) bottom);
        final Rect dst = new Rect((int) dst_left, (int) dst_top, (int) dst_right, (int) dst_bottom);
        final RectF rectF = new RectF(dst);
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, src, dst, paint);
        return output;
}
}

然後，在合適的地方使用他

PhotoUtil photoUtil = new PhotoUtil();

bitmap = photoUtil.toRoundBitmap(bitmap);

如此，就可以實現了