在 iPhone 模拟器上使用 UIImagePickerController

Question

我有一个方法，可以从相册或相机中获取照片。

-(IBAction) getPhoto:(id) sender {
  UIImagePickerController * picker = [[UIImagePickerController alloc] init];
  picker.delegate = self;

  if((UIButton *) sender == choosePhotoBtn) {
        picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
  } else {
        picker.sourceType = UIImagePickerControllerSourceTypeCamera;
  }

  [self presentModalViewController:picker animated:YES];
}

但是当我在模拟器上运行它时，代码无法正常工作。并且在 picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum 和 picker.sourceType = UIImagePickerControllerSourceTypeCamera 中也无法正常工作。

问题是出现在模拟器还是代码中？

- Eugene Trapeznikov

---

这是答案：http://stackoverflow.com/questions/833210/iphone-no-saved-photo-album-created-on-iphone - Raptor

你正在使用 iPhone 模拟器还是 iPad 模拟器？ - Krrish

iPhone模拟器。我将“UIImagePickerControllerSourceTypeSavedPhotosAlbum”更改为“UIImagePickerControllerSourceTypePhotoLibrary”，但是库为空，应该在哪里添加照片，以便在应用程序中使用它们？ - Eugene Trapeznikov

是的，这是因为您正在使用模拟器。 - Elijah Murray

Answer 1

请尝试以下方法，

 if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary])
        {
            picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
        }
        else
        {
            picker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
        }
        [self.navigationController presentModalViewController:picker animated:NO];

如果你正在为iPad创建应用程序，你将需要在一个弹出控件中展示画廊。

- Krrish

---

[self.navigationController presentModalViewController:picker animated:NO] - 不起作用，但是 [self presentModalViewController:picker animated:YES] 是可以的。关于 sourceType，我有同样的问题。为什么 UIImagePickerControllerSourceTypePhotoLibrary 是空的？在运行应用程序之前应该如何添加照片？ - Eugene Trapeznikov

Answer 2

Swift 3/4/5 版本：

if UIImagePickerController.isSourceTypeAvailable(.camera) {
    picker.sourceType = .camera
}
else {
    picker.sourceType = .savedPhotosAlbum // or .photoLibrary
}

Swift 2版本：

if UIImagePickerController.isSourceTypeAvailable(.Camera) {
    picker.sourceType = .Camera
}
else {
    picker.sourceType = .SavedPhotosAlbum // or .PhotoLibrary
}

在模拟器中，你无法使用 cameraCaptureMode 和 showsCameraControls。请注意，这是一种技术术语，涉及到IT领域的相关知识。

- KlimczakM

Answer 3

在模拟器中，当您的选择器.sourceType = UIImagePickerControllerSourceTypeCamera时，由于模拟器中没有可用的相机，因此不会被调用。另外，检查源类型是否可用以避免崩溃是一个好习惯。

#import <MobileCoreServices/UTCoreTypes.h>
….
 if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
        {
            UIImagePickerController *imagePickerCamera =[[UIImagePickerController alloc] init];
            imagePickerCamera.delegate = self;
            imagePickerCamera.mediaTypes = [NSArray arrayWithObjects:(NSString *) kUTTypeImage,nil];
            imagePickerCamera.allowsEditing = YES;
            imagePickerCamera.sourceType = UIImagePickerControllerSourceTypeCamera;

            [self presentViewController:imagePickerCamera  animated:YES completion:nil];
        }

    else if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeSavedPhotosAlbum])
        {
            UIImagePickerController *imagePickerAlbum =[[UIImagePickerController alloc] init];
            imagePickerAlbum.delegate = self;
            imagePickerAlbum.mediaTypes = [NSArray arrayWithObjects:(NSString *) kUTTypeImage,nil];
            imagePickerAlbum.allowsEditing = YES;
            imagePickerAlbum.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

            [self presentViewController:imagePickerAlbum animated:YES completion:nil];
        }

- Meera

---

请查看此链接 - https://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIImagePickerController_Class/UIImagePickerController_Class.pdf - Meera

Answer 4

与上面的答案类似，但我发现这更容易。如果设备没有相机（如模拟器），则显示弹出警报。相同代码，不同用途：

//button if to take a photo
- (IBAction)takePhoto:(id)sender {

//checks if device has a camera
    if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
        UIAlertView *noCameraAlert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"You don't have a camera for this device" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];

        //shows above alert if there's no camera
        [noCameraAlert show];
    }

    //otherwise, show a modal for taking a photo
    else {
        UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
        imagePicker.delegate = self;
        imagePicker.allowsEditing = YES;
        imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;

        [self presentViewController:imagePicker animated:YES completion:NULL];
    }
}

- Elijah Murray