Android-切换头像（设置圆形头像）

1.声明View相关

  private ImageView img_self;
    private Bitmap head;// 头像Bitmap
    private static String path = "/sdcard/qingning/";// sd路径
 

img_self= (ImageView) view.findViewById(R.id.img_self);
        Bitmap src = BitmapFactory.decodeFile(path + "head.jpg");// 从SD卡中找头像，转换成Bitmap
        if (src != null) {
            @SuppressWarnings("deprecation")
            Drawable drawable = new BitmapDrawable(src);// 转换成drawable
            img_self.setImageDrawable(drawable);
        } else {
            /**
             * 如果SD里面没有则需要从服务器取头像，取回来的头像再保存在SD中
             *
             */
        }

//        img转化成圆形
        setImgViewCircle(img_self);


        img_self.setOnClickListener(this);

2.其余详见代码

 @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.img_self:
//                showTypeDialog();
                Intent intent1 = new Intent(Intent.ACTION_PICK, null);
                intent1.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
                startActivityForResult(intent1, 1);
            break;
        }
    }
@Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode) {
            case 1://相册选取
                if (resultCode == RESULT_OK) {
                    cropPhoto(data.getData());// 裁剪图片
                }

                break;
            case 3://裁剪之后的结果
                if (data != null) {
                    Bundle extras = data.getExtras();
                    head = extras.getParcelable("data");
                    if (head != null) {
                        /**
                         * 上传服务器代码
                         */
                        setPicToView(head);// 保存在SD卡中
                        img_self.setImageBitmap(head);// 用ImageView显示出来


//        img转化成圆形
                        setImgViewCircle(img_self);
                    }
                }
                break;
            default:
                break;

        }
        super.onActivityResult(requestCode, resultCode, data);
    }


//图片设为圆形
  public void setImgViewCircle(ImageView img){
        Bitmap src = ((BitmapDrawable)img.getDrawable()).getBitmap();
        Bitmap dst;
//将长方形图片裁剪成正方形图片
        if (src.getWidth() >= src.getHeight()){
            dst = Bitmap.createBitmap(src, src.getWidth()/2 - src.getHeight()/2, 0, src.getHeight(), src.getHeight()
            );
        }else{
            dst = Bitmap.createBitmap(src, 0, src.getHeight()/2 - src.getWidth()/2, src.getWidth(), src.getWidth()
            );
        }
        RoundedBitmapDrawable roundedBitmapDrawable = RoundedBitmapDrawableFactory.create(getResources(), dst);
        roundedBitmapDrawable.setCornerRadius(dst.getWidth() / 2); //设置圆角半径为正方形边长的一半
        roundedBitmapDrawable.setAntiAlias(true);
        img_self.setImageDrawable(roundedBitmapDrawable);

    }
    /**
     * 调用系统的裁剪功能
     *
     * @param uri
     */
    public void cropPhoto(Uri uri) {
        Intent intent = new Intent("com.android.camera.action.CROP");
        intent.setDataAndType(uri, "image/*");
        intent.putExtra("crop", "true");
        // aspectX aspectY 是宽高的比例
        intent.putExtra("aspectX", 1);
        intent.putExtra("aspectY", 1);
        // outputX outputY 是裁剪图片宽高
        intent.putExtra("outputX", 150);
        intent.putExtra("outputY", 150);
        intent.putExtra("return-data", true);
        startActivityForResult(intent, 3);
    }

    private void setPicToView(Bitmap mBitmap) {
        String sdStatus = Environment.getExternalStorageState();
        if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用
            return;
        }
        FileOutputStream b = null;
        File file = new File(path);
        file.mkdirs();// 创建文件夹
        String fileName = path + "head.jpg";// 图片名字
        try {
            b = new FileOutputStream(fileName);
            mBitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把数据写入文件
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } finally {
            try {
                // 关闭流
                b.flush();
                b.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

}

若不成功，记得加权限哦