#import <MediaPlayer/MediaPlayer.h>
#import <MobileCoreServices/MobileCoreServices.h>
#import <AVFoundation/AVFoundation.h>
#import <AssetsLibrary/AssetsLibrary.h>
@interface XXViewController ()
<
UIImagePickerControllerDelegate,
UINavigationControllerDelegate  //相机导航栏
>
@property(nonatomic, strong) UIImagePickerController *CamreaPicker;//相机
@property(nonatomic, strong) UIImagePickerController *PhotoPicker;//相册
@property(nonatomic, strong) AVCaptureSession *AVSession;
@end

//启动相册
-(void)openPhoto{
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleAlert];
    [alert addAction:[UIAlertAction actionWithTitle:@"打开本地相册" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        [self transferCameraAndPhoto:100];
    }]];
    [alert addAction:[UIAlertAction actionWithTitle:@"打开相机" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        [self transferCameraAndPhoto:200];
    }]];
    [self presentViewController:alert animated:YES completion:nil];
}

-(void)transferCameraAndPhoto:(NSInteger)SkinType{ 
    switch (SkinType) {
        case 100:
            //判断是否可以打开相机
            if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
                _CamreaPicker = [[UIImagePickerController alloc]init];
                _CamreaPicker.delegate = self;
                _CamreaPicker.allowsEditing = YES;
                //摄像头
                _CamreaPicker.sourceType = UIImagePickerControllerSourceTypeCamera;
                [self presentViewController:_CamreaPicker animated:YES completion:nil];
            }else{
                UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"对不起，未检测到摄像头，无法进行拍照" preferredStyle:UIAlertControllerStyleAlert];
                [alert addAction:[UIAlertAction actionWithTitle:@"确认" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
                    
                }]];
                [self presentViewController:alert animated:YES completion:nil];
            }
            break;
        case 200:
            if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) {
                _PhotoPicker = [[UIImagePickerController alloc]init];
                _PhotoPicker.delegate = self;
                _PhotoPicker.allowsEditing = YES;
                _PhotoPicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
                [self presentViewController:_PhotoPicker animated:YES completion:nil];
            }
            break;
            
        default:
            break;
    }
}

//开闪光灯

-(void)openFlashLight{
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    
    if (device.torchMode == AVCaptureTorchModeOff) {
        self.AVSession = [[AVCaptureSession alloc]init];
        AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:nil];
        [_AVSession addInput:input];
        
        AVCaptureVideoDataOutput *output = [[AVCaptureVideoDataOutput alloc]init];
        [_AVSession addOutput:output];
        
        [_AVSession beginConfiguration];
        [device lockForConfiguration:nil];
        
        // Set torch to on
        [device setTorchMode:AVCaptureTorchModeOn];
        
        [device unlockForConfiguration];
        [_AVSession commitConfiguration];
        
        // Start the session
        [_AVSession startRunning];
        
        // Keep the session around
        [self setAVSession:self.AVSession];
    }
}

//关闪光灯

-(void)closeFlashLight{
    [self.AVSession stopRunning];
}

//相机回调函数
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{
    //获取图片名字
    UIImage *image = [info objectForKey:UIImagePickerControllerEditedImage];
    //获取图片的名字 
    if (image !=nil) {
        NSURL *imageURL = [info valueForKey:UIImagePickerControllerReferenceURL];
        
        ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset){
            ALAssetRepresentation *representation = [myasset defaultRepresentation];
            NSString *photoName = [representation filename];
            
        };
        ALAssetsLibrary* assetslibrary = [[ALAssetsLibrary alloc] init];
        [assetslibrary assetForURL:imageURL resultBlock:resultblock failureBlock:nil];
        [picker dismissViewControllerAnimated:true completion:nil];
    }
    if (picker == _CamreaPicker) {
        //得到图片
        //存入相册
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
        [self dismissViewControllerAnimated:YES completion:nil];
    } 
}

PS:在info.plist中添加下面的，可以打开相机相册权限
相机： <key>NSCameraUsageDescription</key>
<string>cameraDesciption</string>

相册： <key>NSPhotoLibraryUsageDescription</key>
<string>photoLibraryDesciption</string>

**实现调用相机，相册的demo中借鉴了诸多前辈的开发博客，在此根据自己开发中遇到的问题统一整理成此篇，向前辈们表示感谢和致敬。 ``