xcode changing view controllers issues - ios

I have been developing an iPhone app and have come across a few issues. I do not have a storyboard in my app and have nothing in my xibs. I have initialised and set everything up through code. When I go to the GameViewController from my main viewcontroller everything is fine, however when I come back through my back button I get this issue:
Presenting view controllers on detached view controllers is discouraged .
When I re-arrive to the main view controller, there are little changes such as the view changing before its supposed to. Here is the code for the button on my
GameViewController *game = [[GameViewController alloc] initWithNibName:nil bundle:Nil];
[self dismissViewControllerAnimated:YES completion:NULL];
[self presentViewController:game animated:YES completion:NULL];
Here is the code for the back button:
ViewController *home = [[ViewController alloc] initWithNibName:nil bundle:nil];
[self dismissViewControllerAnimated:YES completion:NULL];
[self presentViewController:home animated:NO completion:NULL];
If anyone can help me to see what I am doing wrong that would be great.

You can not present home view controller from self because it is already dismissed. You should change
[self dismissViewControllerAnimated:YES completion:NULL];
[self presentViewController:home animated:NO completion:NULL];
to
UIViewController *parentViewController = self.presentingViewController;
[self dismissViewControllerAnimated:YES completion:^
{
[parentViewController presentViewController:home animated:NO completion:nil];
}];

Related

PresentViewController dismiss doesn`t go back to previous viewController

On my project we have three windows A, B and C. From A I would like to push view B, and from B I would like to present view C.
My code:
ViewController A:
ViewControllerB *vcB = [[viewControllerB alloc]
initWithNibName:#"ViewControllerB" bundle:nil];
[[self navigationController] pushViewController:vcB animated:YES];
View Controller B:
ViewControllerC *vcC = [[ViewControllerC alloc]
initWithNibName:#"ViewControllerC" bundle:nil];
[self presentViewController:vcC animated: true completion: nil];
Everything is ok until now, but when I dismiss the last view controller with:
[[self presentingViewController] dismissViewControllerAnimated:NO completion:nil];
The app goes back to first view controller (vcA) instead the second one (vcB)
What am I doing wrong?
Thank you, guys.
You must be doing something else that you're not telling us about...
This works as expected:
In MyFirstViewController.m
- (IBAction)pushTapped:(id)sender {
MyPushedViewController *vc = [[MyPushedViewController alloc] initWithNibName:#"MyPushedViewController" bundle:nil];
[self.navigationController pushViewController:vc animated:YES];
}
In MyPushedViewController.m
- (IBAction)presentTapped:(id)sender {
MyPresentedViewController *vc = [[MyPresentedViewController alloc] initWithNibName:#"MyPresentedViewController" bundle:nil];
[self presentViewController:vc animated:YES completion:nil];
}
In MyPresentedViewController.m
- (IBAction)dismissTapped:(id)sender {
[self dismissViewControllerAnimated:NO completion:nil];
}
Tapping the "dismiss" button in MyPresentedViewController dismisses the presented view controller (your vcC), leaving me at MyPushedViewController (your vcB) ... NOT at MyFirstViewController (your vcA).
try this to dismiss vc
[self dismissViewControllerAnimated:NO completion:nil]
and use this to pop
[self.navigationController popToViewController:controller animated:YES];
[self presentingViewController] = Bvc , so here you actually dismissing B not C
[Bvc dismissViewControllerAnimated:NO completion:nil];
but self = Cvc so here you dismissing C only
[self dismissViewControllerAnimated:NO completion:nil];

Creating modal view from another modal view fails

In a view that was created modally, pressing a button causes the modal view to be dismissed and another modal view to load.
- (void)loadLanguageSelectionView {
[self dismissViewControllerAnimated:YES completion:nil];
UIViewController *languageSelectionController = [[LanguageSelectionViewController alloc] initWithNibName:nil bundle:nil];
[languageSelectionController setModalPresentationStyle:UIModalPresentationCustom];
[languageSelectionController setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
[self presentViewController:languageSelectionController animated:YES completion:nil];
}
The following error is thrown when this code block executes:
DenkoStation[4259:73173] Warning: Attempt to present <LanguageSelectionViewController: 0x7b185430> on <ViewController: 0x79f52e50> whose view is not in the window hierarchy!
What surprises me is the fact that the code was running happily before I made some changes to my code as outlined here.
Where's the mistake?
Because you are trying to present a viewController on top of a viewController which is already dismissed and no longer in window hierarchy.
What you can try is, you can take the ParentViewController reference from current viewController and then you can present new viewController on ParentViewController Like This :
- (void)loadLanguageSelectionView {
UIViewController *parentController = self.presentingViewController;
[self dismissViewControllerAnimated:YES completion:^{
UIViewController *languageSelectionController = [[LanguageSelectionViewController alloc] initWithNibName:nil bundle:nil];
[languageSelectionController setModalPresentationStyle:UIModalPresentationCustom];
[languageSelectionController setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
[parentController presentViewController:languageSelectionController animated:YES completion:nil];
}];
}

Display RootViewController only when dismiss current ViewController

I'm doing an ios project without using any story board and xibs.
Here I've come out one problem on presenting my UIViewController.
Here is the senario:
My RootViewController has 2 UIButton's that can present ViewControllerA and ViewControllerB when being pressed.
-(IBAction)btnAclicked:(id)sender{
[self.navigationController presentViewController:ViewControllerA];
}
-(IBAction)btnBclicked:(id)sender{
[self.navigationController presentViewController:ViewControllerB];
}
And now inside ViewControllerA
I have a button to presentViewContollerB as well, and I want only the RootViewController to be displayed when I dismiss ViewContollerB.
In order to do this, I need to dismiss ViewControllerA first then presentViewControllerB. I know there is ways like using delegate to make it works, but I just want to know if there is any easier way to do this.
To be emphasised is that I want to use presentViewController only, not pushViewController. Thanks
I have an answer for your question,just do the following code,
in RootViewController.m
- (IBAction)gotoViewA:(id)sender
{
ViewControllerA *viewControllerA = [[ViewControllerA alloc]initWithNibName:#"ViewControllerA" bundle:nil];
[self presentViewController:viewControllerA animated:YES completion:nil];
}
- (IBAction)gotoViewB:(id)sender
{
ViewControllerB *viewControllerB = [[ViewControllerB alloc]initWithNibName:#"ViewControllerB" bundle:nil];
[self presentViewController:viewControllerB animated:YES completion:nil];
}
in ViewControllerA.m
- (IBAction)actionBackFromA:(id)sender
{
[self dismissViewControllerAnimated:YES completion:nil];
}
in ViewControllerB.m
- (IBAction)actionBackFromB:(id)sender
{
[self dismissViewControllerAnimated:YES completion:nil];
}
Use the completion block of presentviewcontroller,viz will executed first
[self presentViewController:goTo_B animated:YES completion:^{
//Dismiss A
[self dismissViewControllerAnimated:YES completion:nil];
}];
If this does not work,write dismiss and just after it present your new controller
[self dismissViewControllerAnimated:YES completion:nil];
[self.view.window.rootViewController presentViewController:goTo_B animated:YES completion:^{ }];
There's another way out, but i don't know whether its appropriate or not.
Create a property of type View Controller A in view controller B.
While presenting view controller B, assign an instance of View Controller A to the property in view Controller B.
[self presentViewController:goTo_B animated:YES completion:^{
goTo_B.propertyOfViewControllerA = self;
}];
After that while dismissing view controller B you can do the either of the two:
[self dismissViewControllerAnimated:YES completion:nil];
[propertyOfViewControllerA dismissViewControllerAnimated:YES completion:nil]
or
[self dismissViewControllerAnimated:YES completion:^{
[propertyOfViewControllerA dismissViewControllerAnimated:YES completion:nil]
}];

Presenting UIImagePickerController from modal UIViewController

I am trying to have it so a user can choose a photo from their album into an imageview. It seems to work fine if I'm using a push segue to that viewcontroller that has the button to perform the action, but when I change it to modal segue, nothing happens when I click the button to run the function. What is the cause of this exactly?
Method:
- (IBAction)choosePhotoFromAlbum:(id)sender {
UIImagePickerController *imgPicker = [[UIImagePickerController alloc] init];
imgPicker.delegate = self;
imgPicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
[self.navigationController presentViewController:imgPicker animated:YES completion:nil];
}
You're trying to present it from the navigation controller, but your view controller is modal. Change
[self.navigationController presentViewController:imgPicker animated:YES completion:nil];
to
[self presentViewController:imgPicker animated:YES completion:nil];.
you're trying to present it from the navigation controller, but your view controller is modal. so just write
[self presentViewController:YourImagePickerController animated:YES completion:nil];.

Present UIViewController in another one

There is iPad application with UINavigationBar and UITabBar.
I would like to show another UIViewController (clearColored with red UIView as a subview) with "blocking" UINavigationBar and UITabBar from the tap.
How can I do it?
EDITED
if I use [self presentViewController:aboutView animated:YES completion:nil]; :
it covers all with black background ((
[self.tabBarController.navigationController setNavigationBarHidden:TRUE];
[self.navigationController setNavigationBarHidden:TRUE];
self.tabBarController.hidesBottomBarWhenPushed = YES;
[self presentViewController:VC animated:YES completion:nil];
You can present a UIViewController which will obscure the underlying UITabBarController and UINavigationBarController. Try:
[self presentViewController:aViewController animated:YES completion:nil];
Keep in mind that you will be responsible for dismissing this presented view controller by calling dismissViewControllerAnimated: on the presenting view controller.
Try this
ViewController *detailview =[[ViewController alloc]initWithNibName:#"ViewController" bundle:nil]
[self.tabBarController presentViewController:detailview animated:YES completion:nil];

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