UIAlertController *alertVc = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleActionSheet];

        UIAlertAction *cancle = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction *_Nonnull action) {

        }];

        UIAlertAction *camera = [UIAlertAction actionWithTitle:@"打开相机" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {

            UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];

            imagePicker.delegate = self;

            if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]){

                imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;

            }

            [self presentViewController:imagePicker animated:YEScompletion:nil];

        }];

        UIAlertAction *picture = [UIAlertAction actionWithTitle:@"打开相册" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {

            UIImagePickerController *pickerImage = [[UIImagePickerController alloc] init];

            if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {

                pickerImage.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

                pickerImage.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:pickerImage.sourceType];

            }

            pickerImage.delegate = self;

            pickerImage.allowsEditing = NO;

            [self presentViewController:pickerImage animated:YEScompletion:nil];

        }];

        [alertVc addAction:cancle];

        [alertVc addAction:camera];

        [alertVc addAction:picture];

        [self presentViewController:alertVc animated:YES completion:nil];

// 上面写到Button的点击事件方法里，下面直接复制就OK，记得遵守代理协议

UIImagePickerControllerDelegate, UINavigationControllerDelegate

// 选择图片

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

{

    NSString *type = [info objectForKey:UIImagePickerControllerMediaType];

    //当选择的类型是图片

    if ([type isEqualToString:@"public.image"])

    {

        //先把图片转成NSData

        UIImage* image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

        NSData *data;

        if (UIImagePNGRepresentation(image) ==nil)

        {

            data = UIImageJPEGRepresentation(image,1.0);

        }

        else

        {

            data = UIImagePNGRepresentation(image);

        }

        //图片保存的路径

        //这里将图片放在沙盒的documents文件夹中

        NSString *DocumentsPath = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];

        //文件管理器

        NSFileManager *fileManager = [NSFileManager defaultManager];

        //把刚刚图片转换的data对象拷贝至沙盒中并保存为image.png

        [fileManager createDirectoryAtPath:DocumentsPath withIntermediateDirectories:YES attributes:nil error:nil];

        [fileManager createFileAtPath:[DocumentsPath stringByAppendingString:@"/userHeader.png"] contents:data attributes:nil];

        //关闭相册界面

        [picker dismissViewControllerAnimated:YEScompletion:nil];

        //加在视图中

        [self.mineView.headerButton setBackgroundImage:image forState:(UIControlStateNormal)];

    }

}

// 取消选取图片

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker

{

    [picker dismissViewControllerAnimated:YEScompletion:nil];

}

        UIAlertAction *cancle = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction *_Nonnull action) {

        }];

        //修改按钮文字颜色

        [cancle setValue:[UIColor yellowColor] forKey:@"titleTextColor"];