ios - 从库中选择视频时，uiimagepickercontroller didfinishpickingmediawithinfo NOT CALLED

Question

我正在编写一个应用程序，用户可以在其中从库中选择照片和视频。我想在选择视频时实现自己的视频播放器，但应用程序会立即启动具有选择按钮的默认视频播放器。

didfinishpickingmediawithinfo 函数不会被调用。这仅在选择视频时发生。我可以在屏幕上显示选定的照片，因为在选择照片的情况下会调用委托(delegate)方法。

为什么仅当从库中选择视频时不调用选择器的委托(delegate)方法？

库按钮点击代码:

//Library access function displays photos and videos stored on the device
- (IBAction)selectPhoto:(UIButton *)sender {

UIImagePickerController *picker2 = [[UIImagePickerController alloc] init];
picker2.delegate = self;
picker2.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
picker2.mediaTypes =[UIImagePickerController availableMediaTypesForSourceType:picker2.sourceType];
picker2.allowsEditing = NO;

self.picker2 = picker2;

[self.picker dismissViewControllerAnimated:YES completion:^{
    [self presentViewController:self.picker2 animated:YES completion:NULL];}];
}

我确实在 View Controller 中包含了委托(delegate)。我研究过的很多问题都指出 View Controller 的 header 中缺少包含，但我向您保证它们就在那里。

这是包含的代码:

@interface ViewController : UIViewController <UIImagePickerControllerDelegate,UINavigationControllerDelegate,UIGestureRecognizerDelegate>

我在委托(delegate)方法中放置了 NSLog 语句，我发现在使用选择器时，它们在所有其他情况下都会执行。但是，在视频选择的情况下，NSLog 语句不会出现。

如果有人遇到过这个问题并提出解决方案，请分享。我已经搜索了很多天，没有找到解决这个问题的方法。

此人thread有同样的问题，但问题从未解决。

这一切 question必须提供解决方案，我已在我的程序中实现。

我已根据要求添加了以下代码。

委托(delegate)方法:

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

    NSLog(@"didfinishpicking method triggered");
    // Get the type of media selected
    NSString *mediaType = [info objectForKey:UIImagePickerControllerMediaType];

    // Handling Media Capturing (Images/Videos)
    // When an image is taken
    if ([mediaType isEqualToString:(NSString *)kUTTypeImage] && picker.sourceType == UIImagePickerControllerSourceTypeCamera) {

        // Save the taken photo to the camera roll library
        UIImage *imageTaken = [info valueForKey:UIImagePickerControllerOriginalImage];
        UIImageWriteToSavedPhotosAlbum(imageTaken, nil, nil, nil);

        // Update the library button image
        [self.imageButton setImage:imageTaken forState:UIControlStateNormal];

    }

    // When a video is taken
    else if ([mediaType isEqualToString:(NSString *)kUTTypeMovie] && picker.sourceType == UIImagePickerControllerSourceTypeCamera) {

        // Grab the URL for the video just taken
        NSURL *newVideo = [info objectForKey:UIImagePickerControllerMediaURL];

        // Save the video to the camera roll
        UISaveVideoAtPathToSavedPhotosAlbum([newVideo path], nil, nil, nil);


    }

    // Handling Library Previewing
    // When an image is selected
    else if ([mediaType isEqualToString:(NSString *)kUTTypeImage] && picker.sourceType != UIImagePickerControllerSourceTypeCamera) {

        NSLog(@"A picture was selected from the library.");

        UIImage *image = [info valueForKey:UIImagePickerControllerOriginalImage];
        self.libraryImage.image = image;

        self.libraryView.translatesAutoresizingMaskIntoConstraints = YES;

        [[UIApplication sharedApplication].keyWindow addSubview: self.libraryView];

    }

    // When a video is selected
    else if ([mediaType isEqualToString:(NSString *)kUTTypeMovie] && picker.sourceType != UIImagePickerControllerSourceTypeCamera) {
        NSLog(@"A video was selected from the library.");
    }
}

即使按照建议的时间延迟，picker2 仍然损坏。我使用了以下 answer延迟通话。

这是我第一次尝试选择视频然后选择照片时给出的输出。这是在呈现第二个选择器之前先关闭然后延迟运行的。

> 2014-12-30 00:11:57.763 Sneak[228:907] [MPAVController] Autoplay:
> Enabling autoplay 2014-12-30 00:11:57.766 Sneak[228:907]
> [MPAVController] Autoplay: Skipping autoplay, disabled (for current
> item: 0, on player: 1) 2014-12-30 00:11:57.853 Sneak[228:907]
> [MPAVController] Autoplay: Enabling autoplay 2014-12-30 00:11:58.052
> Sneak[228:907] [MPCloudAssetDownloadController] Prioritization
> requested for media item ID: 0 2014-12-30 00:11:58.897 Sneak[228:907]
> [MPAVController] Autoplay: Skipping autoplay, disabled (for current
> item: 0, on player: 1) 2014-12-30 00:11:58.911 Sneak[228:907]
> [MPAVController] Autoplay: _streamLikelyToKeepUp: 0 -> 1 2014-12-30
> 00:12:17.576 Sneak[228:907] didfinishpicking method triggered
> 2014-12-30 00:12:17.579 Sneak[228:907] A picture was selected from the
> library.

我做了更多测试，发现在选择视频时会调用委托(delegate)方法，但只有在默认视频播放器显示上单击选择按钮时才会调用。

我仍然不确定如何在从库中选择视频时直接调用委托(delegate)方法并绕过默认视频播放器。这些额外信息是否会给其他人带来其他想法？

Answer 1

在呈现 picker2 之前设置属性 picker2.allowsEditing=NO

让我知道它是否适合你。