Hiding NavigationBar before and after segue - objective-c

I have an application where a TableView Controller segues to a ViewController and then to another.
I want to maximize real estate in the TVC and use
[self.navigationController setNavigationBarHidden: YES animated:YES];
to hide the bar. However, the bar returns to the view on the return from segue.
The app was constructed in storyboard for 5.1 using Xcode 4.3.1.
Can anyone assist by telling me where I can place a similar instruction to remove the Navbar on return from segue OR suggest an alternative method.
I have exhausted all means in storyboard by changing attributes for the controllers involved. However what you see in Storyboard isn't always what I get.

I found the answer above in the comment so just documenting it because I used it and it worked well! Thanks to #Tomasz.
To prevent the navigation bar reappearing in the header once you go back with the segue, use the following:
-(void)viewWillAppear:(BOOL)animated
{
[self.navigationController setNavigationBarHidden: YES animated:YES];
}

Swift solution
override func viewWillAppear(animated: Bool) {
self.navigationController?.setNavigationBarHidden(true, animated: true)
}
Thanks #spacemonkey and #Tomasz, this worked.

Related

Application tried to present modally an active controller : UIImagePickerController

I'm struggle at this for 2 days and believe that this is the moment I should call for help. After I search SOF for a while, none of any answer could solve my problem. Here are my application ...
In the application,
Device is iPad, iOS 6
RootViewController is NavigationController
TopViewController is TabBarController
In this TabBarController, I present a popoverController from right bar button of navigation bar
In presenting popover there is a button to allow user to pick image from by taking new one or pick from existing.
To pick new one, I presentViewController UIImagePickerController to allow user to take photo with divice camera. presentModalViewController:animated: if iOS < 6, and presentViewController:animated:completion: for iOS > 6
I also hide Status Bar before presentation
To select from existing photo, I do presentPopoverFromBarButtonItem:permitArrowDirections:animated:
PopoverViewController also referencing by A TabBarController
Here is the issue
Present UIImagePickerController will always failed if user try to pick new one first with exception "Application tried to present modally an active controller <[name of view controller that try to present]>"
BUT, if user try to pick image from camera roll for once and then try to take new one again, it won't fail.
Here are what I tried
present from RootViewController
present from TopViewController (TabBarController)
present from popoverViewController itself
present from a tab of TabBarController
hide popoverViewController before presentation
resignFirstResponder from a textField in popoverViewController
Here is the current code I'm using
// PopoverViewController, presented by a tab in TabBarController
- (IBAction)takePhoto:(id)sender {
[self.delegate takePhotoWithDeviceCamera];
}
// A Tab in TabBarController, delegate of popoverViewController
- (void)takePhotoWithCamera {
[[UIApplication sharedApplication] setStatusBarHidden:YES];
if ([UIDevice OSVersion] < 6.0) {
[self presentModalViewController:cameraPicker animated:YES];
} else {
[self presentViewController:cameraPicker animated:YES completion:nil];
}
}
Any idea what would cause this error? Any suggestion are welcome. Thank you.
Got the same trouble than you and finally got the solution based on #CainaSouza's answer. I've been working with Xamarin.iOS so I'll make my answer in C#, but it can be easily translated to Objective-C.
I'm using the same code as #CainaSouza to call the controller:
UIApplication.SharedApplication.KeyWindow.RootViewController.PresentViewController (customController, true, null);
And then I add the following code to my custom RootViewController:
public override void PresentViewController (UIViewController viewControllerToPresent, bool animated, Action completionHandler)
{
if (PresentedViewController != viewControllerToPresent) {
base.PresentViewController (viewControllerToPresent, animated, completionHandler);
}
}
The trick is to check if you haven't presented that UIViewController before.
I know it's an old question, but hope it will help someone. :)
Present the imagePicker controller in a popoverController(in case of iPad). This will not give you that error.
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {
UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:picker];
[popover presentPopoverFromRect:self.selectedImageView.bounds inView:self.selectedImageView permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
self.popOver = popover;
}
else {
[self presentModalViewController:picker animated:YES];
}
Best Regards.
Have you tried to present it like this?
[self.view.window.rootViewController presentModalViewController:cameraPicker animated:YES];
My guess is that the cameraPicker instance is not correctly allocated/released. Try creating the cameraPicker inside your - (void)takePhotoWithCamera method rather than relying on a previously created instance. You'll get a handle to the picker instance in the callback methods...
I had the same problem - I wanted users to take photos using a full screen view (i.e. call presentViewController and pass UIImagePickerController controller instance) and select existing photos from a popover (I associated it with a popover using initWithContentViewController). I reused the same instance of UIImagePickerController for both camera and popover and it threw the same exception if I tried to run a camera before opening a popover.
I turned out to cause a problem and my solution was simply to have two instances of UIImagePickerController - one for camera (which I presented from a main view) and another one for popover. It works so far. :-)
Not sure if it is still actual for the original poster, but hopefully it will help anyone else who encounter this discussion.

Device Orientation in iOS 6.0 UINavigationController

I have a UINavigationController in UITabbarcontroller. I want to rotate only one view cotnroller inside UINavigationController.
Here is the code snippet I am using.
-(NSUInteger)supportedInterfaceOrientations
{
if (CURRENTDEVICE == IPHONE)
return [self.navigationController supportedInterfaceOrientations] | UIInterfaceOrientationMaskAllButUpsideDown;
else
return UIInterfaceOrientationMaskAll;
}
-(BOOL)shouldAutorotate {
return YES;
}
I have a category on UINavigationController as well:
#import "UINavigationController+autorotate.h"
#implementation UINavigationController (autorotate)
- (NSUInteger)supportedInterfaceOrientations
{
return UIInterfaceOrientationMaskAllButUpsideDown;
}
#end
I am not sure how to implement it.
you can hard code it with cgrect. here is a link to another question that might help you. there is a nice example of hard coding two different views for rotation in there, but i don't recomend it personally. anyhow i thought that might point you to the right direction.
https://stackoverflow.com/questions/12867792/ios-rotation-causing-views-to-displace-shift-forcing-me-to-use-non-sensical-har
there is a set of codes in that question that might get you started. you also have an option in starboard( if you are using storyboard) to set rotations in IB which is much easier.
hope this helps
adrian
In your category in the supportedInterfaceOrientations implementation, you could check for the topViewController. You can use kindOfClass: method to work out which class it is... Then return a different orientation from the default of your navigation.
You could also subclass UINavigationController, and do this check the same way. Subclassing the navigation controller isn't recommended until, iOS 6, the documentation still states this but Apple engineers have told me that with the new rotation logic, you can subclass the UINavigationController.

presentModalViewController gives a black screen

In an alert view method I implemented the following (pretty standard) piece of code for popping a modal view:
else if (buttonIndex == 1) {
EmergencyPlanViewController *emergencyPlanView = [[[EmergencyPlanViewController alloc] init] autorelease];
[emergencyPlanView setModalTransitionStyle:UIModalTransitionStyleFlipHorizontal];
[self presentModalViewController:emergencyPlanView animated:YES];
}
Somehow it gives me a black screen as result. I can't find what is wrong here.
I created the window in my MainStoryBoard and customized the class of the viewcontroller in IB to EmergencyPlanViewController.
The viewDidLoad method of the emergencyPlanView is triggered but it looks like the view is not loaded. Anyone an idea what's wrong here?
EDIT:
To be clear, I am not using seperate xib-files in my project. I only use the storyboard
In the xib file, is your UIView set to the File Owner's view. That is probably the problem. Also if you just apply init, that will load the EmergencyPlanViewControllerinterface builder file with the same name:
EmergencyPlanViewController.xib
So make sure in that case that either:
The EmergencyPlanViewController nib is indeed: EmergencyPlanViewController.xib
or that you write instead of init: initWithNibName://whatever nib name here
I managed to fix the black screen issue when presenting a modal view controller by setting a background color to the view in Interface Builder. I noticed that by default the background color of the view is set to something like black/white (see picture attached), although it appears in white. I don't know exactly what does this mean or how it is responsible for showing a black screen, but setting a single color or texture fixed it. PS: I've faced this when migrating from iOS SDK 5 to 6.
ios6
Try this:-
EmergencyPlanViewController *emergencyPlanView=[[EmergencyPlanViewController alloc] initWithNibName:#"EmergencyPlanViewController" bundle:nil];
emergencyPlanView.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self.navigationController presentModalViewController:emergencyPlanView animated:YES];

"Application tried to present modally an active controller"?

I just came across a crash showing a NSInvalidArgumentException with this message on an app which wasn't doing this before.
Application tried to present modally an active controller
UITabBarController: 0x83d7f00.
I have a UITabBarController which I create in the AppDelegate and give it the array of UIViewControllers.
One of them I want to present modally when tapped on it. I did that by implementing the delegate method
- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController
If that view controller is of the class of the one I want to present modally, I return NO and do
[tabBarController presentModalViewController:viewController animated:YES];
And now I'm getting that error, which seems to mean that you can't present modally a view controller that is active somewhere else (in the tabbar...)
I should say I'm on XCode 4.2 Developer Preview 7, so this is iOS 5 (I know about the NDA, but I think I'm not giving any forbidden details). I currently don't have an XCode installation to test if this crashes compiling against the iOS4 SDK, but I'm almost entirely sure it doesn't.
I only wanted to ask if anyone has experienced this issue or has any suggestion
Assume you have three view controllers instantiated like so:
UIViewController* vc1 = [[UIViewController alloc] init];
UIViewController* vc2 = [[UIViewController alloc] init];
UIViewController* vc3 = [[UIViewController alloc] init];
You have added them to a tab bar like this:
UITabBarController* tabBarController = [[UITabBarController alloc] init];
[tabBarController setViewControllers:[NSArray arrayWithObjects:vc1, vc2, vc3, nil]];
Now you are trying to do something like this:
[tabBarController presentModalViewController:vc3];
This will give you an error because that Tab Bar Controller has a death grip on the view controller that you gave it. You can either not add it to the array of view controllers on the tab bar, or you can not present it modally.
Apple expects you to treat their UI elements in a certain way. This is probably buried in the Human Interface Guidelines somewhere as a "don't do this because we aren't expecting you to ever want to do this".
I have the same problem. I try to present view controller just after dismissing.
[self dismissModalViewControllerAnimated:YES];
When I try to do it without animation it works perfectly so the problem is that controller is still alive. I think that the best solution is to use dismissViewControllerAnimated:completion: for iOS5
In my case i was trying to present the viewController (i have the reference of the viewController in the TabBarViewController) from different view controllers and it was crashing with the above message.
In that case to avoid presenting you can use
viewController.isBeingPresented
!viewController.isBeingPresented {
// Present your ViewController only if its not present to the user currently.
}
Might help someone.
The same problem error happened to me when I tried to present a child view controller instead of its UINavigationViewController parent
I had same problem.I solve it. You can try This code:
[tabBarController setSelectedIndex:1];
[self dismissModalViewControllerAnimated:YES];
For React Native Developer - Problem might not be in AppDelegate Or main.m if app has been successfully build and is running and will crash after splash or perhaps the error screen
Issue might be due to use of fonts/resources that is not available with xcode and not properly configured.. You can find out the error by commenting certain portion starting from App.js and drilling inside the navigation/screens and commenting the components till you find the component that is generating the error....
In my case the resource of fontFamily was making an issue which was used right after splash in walkthrough screen
<Text style={{fontFamily: Fonts.roboto}}>ABC</Text>
Here font roboto wasnot configured properly. Wasted entire days just debugging the error hope its helps you
In my case, I was presenting the rootViewController of an UINavigationController when I was supposed to present the UINavigationController itself.
Just remove
[tabBarController presentModalViewController:viewController animated:YES];
and keep
[self dismissModalViewControllerAnimated:YES];
Instead of using:
self.present(viewControllerToPresent: UIViewController, animated: Bool, completion: (() -> Void)?)
you can use:
self.navigationController?.pushViewController(viewController: UIViewController, animated: Bool)
This is my way which supporting multiple Windows(from a single APP) on the iPad and nested modal present.
import UIKit
///✅Use this public method
public func SheetViewController(ViewController:UIViewController) {
for i in returnAvailableViewControllers().shuffled() {
if i.presentedViewController == nil && !ViewController.isViewLoaded {i.present(ViewController, animated: true, completion: {})}
}
}
///Returns all possible ViewControllers
private func returnAvailableViewControllers() -> [UIViewController] {
let 场景 = UIApplication.shared.connectedScenes
var 存储VC : [UIViewController] = []
for i in 场景 {
if i.activationState == .foregroundActive {
//⭐️Set up “foregroundActive” to give the user more control
var 视图控制器 = (i.delegate as? UIWindowSceneDelegate)?.window??.rootViewController
if 视图控制器 != nil {
存储VC.append(视图控制器!)
}
var 结束没 = true
while 结束没 {
//🌟Enumerate all child ViewController
视图控制器 = 视图控制器?.presentedViewController
if 视图控制器 != nil {
存储VC.append(视图控制器!)
} else {
结束没.toggle()
}
}
}
}
return 存储VC
}

viewWillAppear in viewcontrollers of a tabbar

In my tab-bar I have four viewcontrollers, and what happens in one can affect the view of the other, so I may need to reload some elements in the viewcontroller when it becomes visible. Normally I'd fix that by implementing viewWillAppear, but when I switch between the tabs, viewWillAppear does not seem to get called. How can I fix that, or what should I do instead?
Update: as a PS I should add that this is a tabbarcontroller in a navigationcontroller hierarchy
Cheers
Nik
You may use the tabbar controller delegate works like a charm
-(void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController
{
[viewController viewWillAppear:YES];
}
Please see my answer here
iPhone viewWillAppear not firing
And in case you find this question because you would like to update something in the UITabBarController itself, not the UIViewControllers of a UITabBarController, like the OP's question. For example, hiding or displaying a custom UITabBarButton. In Swift 3.0 overriding setNeedsStatusBarAppearanceUpdate of my UITabBarController class worked for me.
override func setNeedsStatusBarAppearanceUpdate() {
}
viewWillAppear should only be used when the view appears, and not for updating it.
Use setNeedsDisplay on the viewController's view instead.