ios 调取相机

1、开权限：

Privacy - Photo Library Usage Description

Privacy - Camera Usage Description、

2、添加代理

UINavigationControllerDelegate,UIImagePickerControllerDelegate

3、实现代理方法：

- (void)openCamera {
    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.allowsEditing = YES; //可编辑
    //判断是否可以打开照相机
    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
        picker.sourceType = UIImagePickerControllerSourceTypeCamera;
        [self presentViewController:picker animated:YES completion:nil];
    } else {
        NSLog(@"没有摄像头");
    }
}

#pragma mark - UIImagePickerControllerDelegate
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info {
    [picker dismissViewControllerAnimated:YES completion:^{}];
    UIImage *theImage = nil;
    if(picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
        theImage = [info objectForKey:UIImagePickerControllerOriginalImage];
        [self.allImage addObject:theImage];
        [self.mainCollectionView reloadData];
    }
}

//进入拍摄页面点击取消按钮
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {
    [self dismissViewControllerAnimated:YES completion:nil];
}