源类型%1不可用

Question

我有一个适用于iPhone和iPad的应用程序，当我尝试在用于iPad的UIPopoverController中加载一个UIPickerViewController时，我得到了异常“源类型1不可用”。即使使用设备也会遇到问题。

@try {
    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])  {
        UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];

        imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
        imagePicker.delegate = self;
        imagePicker.allowsEditing = NO;

        self.tempComp = component;
        if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
            [self presentModalViewController:imagePicker animated:YES];
        }else {
            // We are using an iPad
            popoverController=[[UIPopoverController alloc] initWithContentViewController:imagePicker];
            popoverController.delegate = self;

            [popoverController presentPopoverFromRect:component.bounds inView:component permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
        }
    }else{
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Camera Non Disponibile" message:@"La camera non è disponibile" delegate:self cancelButtonTitle:@"Ok" otherButtonTitles: nil];
        [alert show];
    }
}
@catch (NSException *exception) {
    NSLog(@"Cattura eccezione %@", exception);
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Eccezione" message:[NSString stringWithFormat:@"%@", exception] delegate:self cancelButtonTitle:@"Ok" otherButtonTitles: nil];
    [alert show];
}

Answer 1

这是因为你正在模拟器上打开摄像头...由于代码类似于[UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]，显然模拟器没有camera...继续给出这样的警报，

 if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {

    UIAlertView *myAlertView = [[UIAlertView alloc] initWithTitle:@"Error"
                                                          message:@"Device has no camera."
                                                         delegate:nil
                                                cancelButtonTitle:@"OK"
                                                otherButtonTitles: nil];

    [myAlertView show];

}
else{
     //other action
}

Swift 3：

if !UIImagePickerController.isSourceTypeAvailable(.camera) {
    let alertController = UIAlertController(title: nil, message: "Device has no camera.", preferredStyle: .alert)

    let okAction = UIAlertAction(title: "Alright", style: .default, handler: { (alert: UIAlertAction!) in
    })

    alertController.addAction(okAction)
    self.present(alertController, animated: true, completion: nil)
} else {
    // Other action
}

没什么好担心的，它会在设备上正常工作！

Answer 2

您不能将摄像机与模拟器一起使用，只能与真实设备一起使用。模拟器没有摄像头，即使Mac上有摄像头。

请使用图片库

imagePicker.sourceType = .photoLibrary

而不是

imagePicker.sourceType = .camera

Answer 3

您是否正在尝试在iPhone模拟器中运行该应用程序？

如果是这样的话，模拟器不支持相机功能，只支持从照片库中获取照片。听起来似乎我应该构建一个自动后备，因为很多人都会尝试在模拟器上测试他们的应用程序。