iOS沒有modalViewController從相機拍照

Question

我需要從相機獲取照片，但我需要在我的UIViewController中使用它。 我有拍照的自定義按鈕。

我不想這樣使用

-(void) takePicture:(id) sender 
{
    UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];

    if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) 
    {
        [imagePicker setSourceType:UIImagePickerControllerSourceTypeCamera];
    }
    else 
    {
        [imagePicker setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];
    }
    [imagePicker setDelegate:self];
    [self presentModalViewController:imagePicker animated:YES];
}

我想創建自定義ViewController與來自相機的流，如instagram。 我怎么能這樣做？ 謝謝

Answer 1

您可以使用AVFoundation拍照。 閱讀關於它的蘋果文檔： AVCaptureDevice

這是apple的示例代碼。 AVCam

在這里，我找到了一個教程： 鏈接

另一個stackOverflow問題，在這里有一個很好的示例代碼我認為： 鏈接

另一個有用的鏈接： 鏈接

Answer 2

以下是無需modalViewController即可從相機拍攝照片的AVCam代碼。 感謝incmiko在您的答案中提供此代碼的鏈接。

使用下面的代碼，用戶點擊“takePhoto”按鈕，設備將照片零更改為UI =沒有照片預覽屏幕。 下面的代碼來自蘋果https://developer.apple.com/LIBRARY/IOS/samplecode/AVCam/Introduction/Intro.html，其中包含“額外功能”（與拍攝靜態照片無關）。 謝謝你incmiko在你的答案中建議這段代碼。

- (IBAction)takePhoto:(id)sender {
    [self snapStillImage:sender];
}


#pragma mark - AVFoundation

- (BOOL)isSessionRunningAndDeviceAuthorized
{
    return [[self session] isRunning] && [self isDeviceAuthorized];
}

+ (NSSet *)keyPathsForValuesAffectingSessionRunningAndDeviceAuthorized
{
    return [NSSet setWithObjects:@"session.running", @"deviceAuthorized", nil];
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    [self getDeviceId];

    // Create the AVCaptureSession
    AVCaptureSession *session = [[AVCaptureSession alloc] init];
    [self setSession:session];

    // Check for device authorization
    [self checkDeviceAuthorizationStatus];

    // In general it is not safe to mutate an AVCaptureSession or any of its inputs, outputs, or connections from multiple threads at the same time.
    // Why not do all of this on the main queue?
    // -[AVCaptureSession startRunning] is a blocking call which can take a long time. We dispatch session setup to the sessionQueue so that the main queue isn't blocked (which keeps the UI responsive).

    dispatch_queue_t sessionQueue = dispatch_queue_create("session queue", DISPATCH_QUEUE_SERIAL);
    [self setSessionQueue:sessionQueue];

    dispatch_async(sessionQueue, ^{
        [self setBackgroundRecordingID:UIBackgroundTaskInvalid];

        NSError *error = nil;

        AVCaptureDevice *videoDevice = [CMRootViewController deviceWithMediaType:AVMediaTypeVideo preferringPosition:AVCaptureDevicePositionFront];
        AVCaptureDeviceInput *videoDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:&error];

        if (error)
        {
            NSLog(@"%@", error);
        }

        if ([session canAddInput:videoDeviceInput])
        {
            [session addInput:videoDeviceInput];
            [self setVideoDeviceInput:videoDeviceInput];

            dispatch_async(dispatch_get_main_queue(), ^{
                // Why are we dispatching this to the main queue?
                // Because AVCaptureVideoPreviewLayer is the backing layer for AVCamPreviewView and UIView can only be manipulated on main thread.
                // Note: As an exception to the above rule, it is not necessary to serialize video orientation changes on the AVCaptureVideoPreviewLayer’s connection with other session manipulation.
            });
        }

        AVCaptureDevice *audioDevice = [[AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio] firstObject];
        AVCaptureDeviceInput *audioDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:&error];

        if (error)
        {
            NSLog(@"%@", error);
        }

        if ([session canAddInput:audioDeviceInput])
        {
            [session addInput:audioDeviceInput];
        }

        AVCaptureMovieFileOutput *movieFileOutput = [[AVCaptureMovieFileOutput alloc] init];
        if ([session canAddOutput:movieFileOutput])
        {
            [session addOutput:movieFileOutput];
            AVCaptureConnection *connection = [movieFileOutput connectionWithMediaType:AVMediaTypeVideo];
            if ([connection isVideoStabilizationSupported])
                [connection setEnablesVideoStabilizationWhenAvailable:YES];
            [self setMovieFileOutput:movieFileOutput];
        }

        AVCaptureStillImageOutput *stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
        if ([session canAddOutput:stillImageOutput])
        {
            [stillImageOutput setOutputSettings:@{AVVideoCodecKey : AVVideoCodecJPEG}];
            [session addOutput:stillImageOutput];
            [self setStillImageOutput:stillImageOutput];
        }
    });
}

- (void)viewWillAppear:(BOOL)animated
{
    dispatch_async([self sessionQueue], ^{
        [self addObserver:self forKeyPath:@"sessionRunningAndDeviceAuthorized" options:(NSKeyValueObservingOptionOld | NSKeyValueObservingOptionNew) context:SessionRunningAndDeviceAuthorizedContext];
        [self addObserver:self forKeyPath:@"stillImageOutput.capturingStillImage" options:(NSKeyValueObservingOptionOld | NSKeyValueObservingOptionNew) context:CapturingStillImageContext];
        [self addObserver:self forKeyPath:@"movieFileOutput.recording" options:(NSKeyValueObservingOptionOld | NSKeyValueObservingOptionNew) context:RecordingContext];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(subjectAreaDidChange:) name:AVCaptureDeviceSubjectAreaDidChangeNotification object:[[self videoDeviceInput] device]];

        __weak CMRootViewController *weakSelf = self;
        [self setRuntimeErrorHandlingObserver:[[NSNotificationCenter defaultCenter] addObserverForName:AVCaptureSessionRuntimeErrorNotification object:[self session] queue:nil usingBlock:^(NSNotification *note) {
            CMRootViewController *strongSelf = weakSelf;
            dispatch_async([strongSelf sessionQueue], ^{
                // Manually restarting the session since it must have been stopped due to an error.
                [[strongSelf session] startRunning];
            });
        }]];
        [[self session] startRunning];
    });
}

- (void)viewDidDisappear:(BOOL)animated
{
    dispatch_async([self sessionQueue], ^{
        [[self session] stopRunning];

        [[NSNotificationCenter defaultCenter] removeObserver:self name:AVCaptureDeviceSubjectAreaDidChangeNotification object:[[self videoDeviceInput] device]];
        [[NSNotificationCenter defaultCenter] removeObserver:[self runtimeErrorHandlingObserver]];

        [self removeObserver:self forKeyPath:@"sessionRunningAndDeviceAuthorized" context:SessionRunningAndDeviceAuthorizedContext];
        [self removeObserver:self forKeyPath:@"stillImageOutput.capturingStillImage" context:CapturingStillImageContext];
        [self removeObserver:self forKeyPath:@"movieFileOutput.recording" context:RecordingContext];
    });
}

- (BOOL)prefersStatusBarHidden
{
    return YES;
}

- (BOOL)shouldAutorotate
{
    // Disable autorotation of the interface when recording is in progress.
    return ![self lockInterfaceRotation];
}

- (NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskAll;
}

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
//  [[(AVCaptureVideoPreviewLayer *)[[self previewView] layer] connection] setVideoOrientation:(AVCaptureVideoOrientation)toInterfaceOrientation];
}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
    if (context == CapturingStillImageContext)
    {
        BOOL isCapturingStillImage = [change[NSKeyValueChangeNewKey] boolValue];

        if (isCapturingStillImage)
        {
            [self runStillImageCaptureAnimation];
        }
    }
    else if (context == RecordingContext)
    {
        BOOL isRecording = [change[NSKeyValueChangeNewKey] boolValue];

        dispatch_async(dispatch_get_main_queue(), ^{
            if (isRecording)
            {
//              [[self cameraButton] setEnabled:NO];
//              [[self recordButton] setTitle:NSLocalizedString(@"Stop", @"Recording button stop title") forState:UIControlStateNormal];
//              [[self recordButton] setEnabled:YES];
            }
            else
            {
//              [[self cameraButton] setEnabled:YES];
//              [[self recordButton] setTitle:NSLocalizedString(@"Record", @"Recording button record title") forState:UIControlStateNormal];
//              [[self recordButton] setEnabled:YES];
            }
        });
    }
    else if (context == SessionRunningAndDeviceAuthorizedContext)
    {
        BOOL isRunning = [change[NSKeyValueChangeNewKey] boolValue];

        dispatch_async(dispatch_get_main_queue(), ^{
            if (isRunning)
            {
//              [[self cameraButton] setEnabled:YES];
//              [[self recordButton] setEnabled:YES];
//              [[self stillButton] setEnabled:YES];
            }
            else
            {
//              [[self cameraButton] setEnabled:NO];
//              [[self recordButton] setEnabled:NO];
//              [[self stillButton] setEnabled:NO];
            }
        });
    }
    else
    {
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
    }
}

#pragma mark Actions

- (IBAction)toggleMovieRecording:(id)sender
{
//  [[self recordButton] setEnabled:NO];

    dispatch_async([self sessionQueue], ^{
        if (![[self movieFileOutput] isRecording])
        {
            [self setLockInterfaceRotation:YES];

            if ([[UIDevice currentDevice] isMultitaskingSupported])
            {
                // Setup background task. This is needed because the captureOutput:didFinishRecordingToOutputFileAtURL: callback is not received until AVCam returns to the foreground unless you request background execution time. This also ensures that there will be time to write the file to the assets library when AVCam is backgrounded. To conclude this background execution, -endBackgroundTask is called in -recorder:recordingDidFinishToOutputFileURL:error: after the recorded file has been saved.
                [self setBackgroundRecordingID:[[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:nil]];
            }

            // Update the orientation on the movie file output video connection before starting recording.
//          [[[self movieFileOutput] connectionWithMediaType:AVMediaTypeVideo] setVideoOrientation:[[(AVCaptureVideoPreviewLayer *)[[self previewView] layer] connection] videoOrientation]];

            // Turning OFF flash for video recording
            [CMRootViewController setFlashMode:AVCaptureFlashModeOff forDevice:[[self videoDeviceInput] device]];

            // Start recording to a temporary file.
            NSString *outputFilePath = [NSTemporaryDirectory() stringByAppendingPathComponent:[@"movie" stringByAppendingPathExtension:@"mov"]];
            [[self movieFileOutput] startRecordingToOutputFileURL:[NSURL fileURLWithPath:outputFilePath] recordingDelegate:self];
        }
        else
        {
            [[self movieFileOutput] stopRecording];
        }
    });
}

- (IBAction)changeCamera:(id)sender
{
//  [[self cameraButton] setEnabled:NO];
//  [[self recordButton] setEnabled:NO];
//  [[self stillButton] setEnabled:NO];

    dispatch_async([self sessionQueue], ^{
        AVCaptureDevice *currentVideoDevice = [[self videoDeviceInput] device];
        AVCaptureDevicePosition preferredPosition = AVCaptureDevicePositionUnspecified;
        AVCaptureDevicePosition currentPosition = [currentVideoDevice position];

        switch (currentPosition)
        {
            case AVCaptureDevicePositionUnspecified:
                preferredPosition = AVCaptureDevicePositionBack;
                break;
            case AVCaptureDevicePositionBack:
                preferredPosition = AVCaptureDevicePositionFront;
                break;
            case AVCaptureDevicePositionFront:
                preferredPosition = AVCaptureDevicePositionBack;
                break;
        }

        AVCaptureDevice *videoDevice = [CMRootViewController deviceWithMediaType:AVMediaTypeVideo preferringPosition:preferredPosition];
        AVCaptureDeviceInput *videoDeviceInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:nil];

        [[self session] beginConfiguration];

        [[self session] removeInput:[self videoDeviceInput]];
        if ([[self session] canAddInput:videoDeviceInput])
        {
            [[NSNotificationCenter defaultCenter] removeObserver:self name:AVCaptureDeviceSubjectAreaDidChangeNotification object:currentVideoDevice];

            [CMRootViewController setFlashMode:AVCaptureFlashModeAuto forDevice:videoDevice];
            [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(subjectAreaDidChange:) name:AVCaptureDeviceSubjectAreaDidChangeNotification object:videoDevice];

            [[self session] addInput:videoDeviceInput];
            [self setVideoDeviceInput:videoDeviceInput];
        }
        else
        {
            [[self session] addInput:[self videoDeviceInput]];
        }

        [[self session] commitConfiguration];

        dispatch_async(dispatch_get_main_queue(), ^{
//          [[self cameraButton] setEnabled:YES];
//          [[self recordButton] setEnabled:YES];
//          [[self stillButton] setEnabled:YES];
        });
    });
}

- (IBAction)snapStillImage:(id)sender
{
    dispatch_async([self sessionQueue], ^{
        // Update the orientation on the still image output video connection before capturing.
//      [[[self stillImageOutput] connectionWithMediaType:AVMediaTypeVideo] setVideoOrientation:[[(AVCaptureVideoPreviewLayer *)[[self previewView] layer] connection] videoOrientation]];

        // Flash set to Auto for Still Capture
        [CMRootViewController setFlashMode:AVCaptureFlashModeAuto forDevice:[[self videoDeviceInput] device]];

        // Capture a still image.
        [[self stillImageOutput] captureStillImageAsynchronouslyFromConnection:[[self stillImageOutput] connectionWithMediaType:AVMediaTypeVideo] completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error) {

            if (imageDataSampleBuffer)
            {
                NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
                UIImage *image = [[UIImage alloc] initWithData:imageData];

                [self saveImageToCloud:image];
                self.checkMarkTakePhoto.hidden = NO;

            }
        }];
    });
}

- (IBAction)focusAndExposeTap:(UIGestureRecognizer *)gestureRecognizer
{
//  CGPoint devicePoint = [(AVCaptureVideoPreviewLayer *)[[self previewView] layer] captureDevicePointOfInterestForPoint:[gestureRecognizer locationInView:[gestureRecognizer view]]];
//  [self focusWithMode:AVCaptureFocusModeAutoFocus exposeWithMode:AVCaptureExposureModeAutoExpose atDevicePoint:devicePoint monitorSubjectAreaChange:YES];
}

- (void)subjectAreaDidChange:(NSNotification *)notification
{
    CGPoint devicePoint = CGPointMake(.5, .5);
    [self focusWithMode:AVCaptureFocusModeContinuousAutoFocus exposeWithMode:AVCaptureExposureModeContinuousAutoExposure atDevicePoint:devicePoint monitorSubjectAreaChange:NO];
}

#pragma mark File Output Delegate

- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL fromConnections:(NSArray *)connections error:(NSError *)error
{
    if (error)
        NSLog(@"%@", error);

    [self setLockInterfaceRotation:NO];

    // Note the backgroundRecordingID for use in the ALAssetsLibrary completion handler to end the background task associated with this recording. This allows a new recording to be started, associated with a new UIBackgroundTaskIdentifier, once the movie file output's -isRecording is back to NO — which happens sometime after this method returns.
    UIBackgroundTaskIdentifier backgroundRecordingID = [self backgroundRecordingID];
    [self setBackgroundRecordingID:UIBackgroundTaskInvalid];

    [[[ALAssetsLibrary alloc] init] writeVideoAtPathToSavedPhotosAlbum:outputFileURL completionBlock:^(NSURL *assetURL, NSError *error) {
        if (error)
            NSLog(@"%@", error);

        [[NSFileManager defaultManager] removeItemAtURL:outputFileURL error:nil];

        if (backgroundRecordingID != UIBackgroundTaskInvalid)
            [[UIApplication sharedApplication] endBackgroundTask:backgroundRecordingID];
    }];
}

#pragma mark Device Configuration

- (void)focusWithMode:(AVCaptureFocusMode)focusMode exposeWithMode:(AVCaptureExposureMode)exposureMode atDevicePoint:(CGPoint)point monitorSubjectAreaChange:(BOOL)monitorSubjectAreaChange
{
    dispatch_async([self sessionQueue], ^{
        AVCaptureDevice *device = [[self videoDeviceInput] device];
        NSError *error = nil;
        if ([device lockForConfiguration:&error])
        {
            if ([device isFocusPointOfInterestSupported] && [device isFocusModeSupported:focusMode])
            {
                [device setFocusMode:focusMode];
                [device setFocusPointOfInterest:point];
            }
            if ([device isExposurePointOfInterestSupported] && [device isExposureModeSupported:exposureMode])
            {
                [device setExposureMode:exposureMode];
                [device setExposurePointOfInterest:point];
            }
            [device setSubjectAreaChangeMonitoringEnabled:monitorSubjectAreaChange];
            [device unlockForConfiguration];
        }
        else
        {
            NSLog(@"%@", error);
        }
    });
}

+ (void)setFlashMode:(AVCaptureFlashMode)flashMode forDevice:(AVCaptureDevice *)device
{
    if ([device hasFlash] && [device isFlashModeSupported:flashMode])
    {
        NSError *error = nil;
        if ([device lockForConfiguration:&error])
        {
            [device setFlashMode:flashMode];
            [device unlockForConfiguration];
        }
        else
        {
            NSLog(@"%@", error);
        }
    }
}

+ (AVCaptureDevice *)deviceWithMediaType:(NSString *)mediaType preferringPosition:(AVCaptureDevicePosition)position
{
    NSArray *devices = [AVCaptureDevice devicesWithMediaType:mediaType];
    AVCaptureDevice *captureDevice = [devices firstObject];

    for (AVCaptureDevice *device in devices)
    {
        if ([device position] == position)
        {
            captureDevice = device;
            break;
        }
    }

    return captureDevice;
}

#pragma mark UI

- (void)runStillImageCaptureAnimation
{
/*
    dispatch_async(dispatch_get_main_queue(), ^{
        [[[self previewView] layer] setOpacity:0.0];
        [UIView animateWithDuration:.25 animations:^{
            [[[self previewView] layer] setOpacity:1.0];
        }];
    });
*/
}

- (void)checkDeviceAuthorizationStatus
{
    NSString *mediaType = AVMediaTypeVideo;

    [AVCaptureDevice requestAccessForMediaType:mediaType completionHandler:^(BOOL granted) {
        if (granted)
        {
            //Granted access to mediaType
            [self setDeviceAuthorized:YES];
        }
        else
        {
            //Not granted access to mediaType
            dispatch_async(dispatch_get_main_queue(), ^{
                [[[UIAlertView alloc] initWithTitle:@"AVCam!"
                                            message:@"AVCam doesn't have permission to use Camera, please change privacy settings"
                                           delegate:self
                                  cancelButtonTitle:@"OK"
                                  otherButtonTitles:nil] show];
                [self setDeviceAuthorized:NO];
            });
        }
    }];
}