Question

我有一个Tab栏控制器，当我点击第三个标签栏按钮时，我出现UIViewcontroller。在这个vc的viewWillAppear中，我提出的UIImagepickerController工作正常。问题是当我打开视图时，我无法立即在屏幕上显示它。首先，vc出现在0.4-0.5秒后的图像选择器。所以我想首先呈现图像选择器并在用户拍摄图像后呈现vc。我也尝试从viewDidLoad和viewWillAppear调用选择器，但没有任何改变。

- (void)viewWillAppear:(BOOL)animated {

    [super viewWillAppear:animated];

    if (imagePickerWasPresented == NO)
    {
        imagePickerWasPresented = YES;

        self.imagePicker = [[UIImagePickerController alloc] init];
        self.imagePicker.delegate = self;
        self.imagePicker.allowsEditing = YES;


        self.imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
        self.imagePicker.mediaTypes = [NSArray arrayWithObject:(NSString *)kUTTypeImage];

        [self presentViewController:self.imagePicker animated:NO completion:nil];
    }
}

我是在错误的地方打电话吗？

Answer 1

我有同样的问题 - 而不是调用VC然后调用UIImagePicker，直接调用UIImagePicker。

完成拍照/录像时：

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

您将转到此标准委托方法，从此处调用VC。通过这种方式，您将立即转到ImagePicker，并且只有转换才会选择对之后拍摄的内容执行某些操作，这样不那么令人沮丧/丑陋。

Answer 2

不，你在一个好的地方调用它，这就是iOS的用途;如果你在彼此之上呈现多个模态，则会一个接一个地呈现，包括动画。适用于您的问题的解决方案是提供UINavigationController而不是UIViewController。将导航控制器设置为将ViewController作为根视图控制器，但也将imagepickercontroller推送到堆栈。介绍这个导航控制器，它应该直接到你的imagepickercontroller。否则，尝试将动画设置为NO的uiviewcontroller和imagepickercontroller同时显示，看看是否有效。

Answer 3

尝试这一点，看看有多接近，然后适应您的需求。当我给它一个快速测试时，它似乎做了你所要求的。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] ;

    UIViewController * vc = [[UIViewController alloc] init];

    vc.view.backgroundColor = [UIColor whiteColor];

    UINavigationController * navigationController = [[UINavigationController alloc] init];
    [navigationController pushViewController:vc animated:NO];


    UITabBarController * tabBarController = [[UITabBarController alloc] init];
    NSArray* controllers = [NSArray arrayWithObjects:navigationController, nil];
    tabBarController.viewControllers = controllers;

    tabBarController.delegate = self;

    UIImagePickerController *imagePicker =
    [[UIImagePickerController alloc] init];
    imagePicker.delegate = self;
    imagePicker.sourceType =
    UIImagePickerControllerSourceTypePhotoLibrary;
    imagePicker.mediaTypes = [NSArray arrayWithObjects:
                          (NSString *) kUTTypeImage,
                          nil];
    imagePicker.allowsEditing = NO;

    self.window.rootViewController = tabBarController;

    [self.window makeKeyAndVisible];

    [vc presentViewController:imagePicker animated:NO completion:nil];

    return YES;

}

Answer 4

UIImage作为PopOver

图库模式：

BOOL hasGallery = [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary];
UIImagePickerController* picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = hasGalleryt ? UIImagePickerControllerSourceTypePhotoLibrary :    UIImagePickerControllerSourceTypePhotoLibrary;
if (self.popoverController != nil)
{
    [self.popoverController dismissPopoverAnimated:YES];
    self.popoverController=nil;
}
self.popoverController = [[UIPopoverController alloc] initWithContentViewController:picker];
CGRect popoverRect = [self.view convertRect:[self.imageView frame]
                                   fromView:[self.imageView superview]];
popoverRect.size.width = MIN(popoverRect.size.width, 300) ;
popoverRect.origin.x = popoverRect.origin.x;
[self.popoverController
 presentPopoverFromRect:popoverRect
 inView:self.view
 permittedArrowDirections:UIPopoverArrowDirectionAny
 animated:YES];

相机模式：

BOOL hasCamera = [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera];
UIImagePickerController* picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = hasCamera ? UIImagePickerControllerSourceTypeCamera :    UIImagePickerControllerSourceTypePhotoLibrary;
if (self.popoverController != nil)
{
    [self.popoverController dismissPopoverAnimated:YES];
    self.popoverController = nil;
}
self.popoverController = [[UIPopoverController alloc] initWithContentViewController:picker];
CGRect popoverRect = [self.view convertRect:[self.imageView frame]
                                   fromView:[self.imageView superview]];
popoverRect.size.width = MIN(popoverRect.size.width, 300) ;
popoverRect.origin.x = popoverRect.origin.x;
[self.popoverController
 presentPopoverFromRect:popoverRect
 inView:self.view
 permittedArrowDirections:UIPopoverArrowDirectionAny
 animated:YES];

请记得向代表们提供.h文件@interface，如下所示：

@interface the UIViewController: UIViewController <UIPopoverControllerDelegate, UIImagePickerControllerDelegate>

无法立即呈现imagepicker

4 个答案:

UIImage作为PopOver