使用相册、相机

首先需要在info.plist文件中添加以下键值对：

<key>NSCameraUsageDescription</key>
    <string>使用相机</string>

<key>NSPhotoLibraryUsageDescription</key>
    <string>使用相册</string>

剩下的废话不多说，直接上代码：

#pragma mark -- 点击添加用户的头像
-(void)addUserHeadImg:(UIButton *)btn{
    if (_user) {
        UIAlertController *alert = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleActionSheet];
        __weak typeof(self) weakSelf = self;
        [alert addAction:[UIAlertAction actionWithTitle:@"拍照" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
                [weakSelf showImagePickerVCWithType:UIImagePickerControllerSourceTypeCamera];
            }
        }]];
        [alert addAction:[UIAlertAction actionWithTitle:@"从相册选取" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            [weakSelf showImagePickerVCWithType:UIImagePickerControllerSourceTypePhotoLibrary];
        }]];
        [alert addAction:[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil]];
        [self presentViewController:alert animated:YES completion:nil];
    }
}

//拍照
-(void)showImagePickerVCWithType:(UIImagePickerControllerSourceType)type{
    //创建pickerVC
    UIImagePickerController *pickerVC = [[UIImagePickerController alloc] init];
    //设置图片来源，可以使相机/相册
    pickerVC.sourceType = type;
    pickerVC.allowsEditing = YES;
    pickerVC.delegate = self;
    //弹出pickerVC
    [self presentViewController:pickerVC animated:YES completion:nil];
}

#pragma mark -- 获取用户选择的图片代理

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{
    UIImage *img = info[@"UIImagePickerControllerEditedImage"];
    [_headImgV setImage:img forState:UIControlStateNormal];
    [_headImgV setImageEdgeInsets:UIEdgeInsetsZero];

    [self upDataHeadImageBox:img];
    [picker dismissViewControllerAnimated:YES completion:nil];
}
#pragma mark -- 把选择的图片存到本地
-(void)upDataHeadImageBox:(UIImage *)img{
    //更新沙盒
    NSMutableData *mutableData = [[NSMutableData alloc] init];
    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:mutableData];
    [archiver encodeObject:img forKey:kHeadKey];
    [archiver finishEncoding];
    [mutableData writeToFile:kFilePath atomically:YES];
}