Back button handling from a view in both present and push - ios

I have a UIViewControllerC which is call from two another UIViewcontroller
ViewControllerA
ViewControllerB
From ViewControllerA to go to UIViewControllerC i have to make it presentviewcontroller
UIViewControllerC *vc = [self.storyboard instantiateViewControllerWithIdentifier:#"UIViewControllerC"];
[vc setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
vc.tagfrom=#"present";
[self presentViewController:vc animated:NO completion:nil];
From ViewControllerB to go to UIViewControllerC i have to make it push view
UIViewControllerC *vc = [self.storyboard instantiateViewControllerWithIdentifier:#"UIViewControllerC"];
[vc setModalTransitionStyle:UIModalTransitionStyleCrossDissolve];
vc.tagfrom=#"push";
[self.navigationController pushViewController:vc animated:YES];
Now i have to back from both view on back button i check tagfrom condition and handle it
-(IBAction)backBtn:(id)sender
{
if ([tagfrom isEqualToString:#"present"])
{
[self dismissViewControllerAnimated:NO completion:nil];
}
else
{
[self.navigationController popViewControllerAnimated:YES];
}
}
Which working fine in both senerio, but sometimes my push view behaves like presentmodelveiw, and having no transition effects in it, please help me to resolve it

First of all, you don't need tagfrom property on your UIViewController subclass.
A UIViewController instance has a property called presentingViewController which will let you know about the viewController ( A in your case ) that presented current viewController ( C in your case ).
-(IBAction)backBtn:(id)sender
{
if (nil != self.presentingViewController) {
[self dismissViewControllerAnimated:NO completion:nil];
}
else {
[self.navigationController popViewControllerAnimated:YES];
}
}
Second, modalTransitionStyle is supposed to work with only presentation and NOT push / pop transitions. If you are using this with push / pop, the behavior is undefined because it is not meant to be used there.

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];

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]
}];

push view controller after dismissing presented view controller

I have this navigation stack
RootVC ---> VC1 --> (presenting)-> ModalVC
and I have VC2 (not in navigation stack).
When presenting ModalVC, I want to click on button in my ModalVC to dismiss ModalVC, then push VC2 into the navigation stack after VC1 at one click. It should look like this:
RootVC ---> VC1 ---> VC2
I tried a lot of methods to make it, but pushing event fire only, when I return to my RootVC.
I tried to make it with delegates:
In ModalVC on click:
[self dismissViewControllerAnimated:YES completion:^{
if ([self.delegate respondsToSelector:#selector(dismissAndPush:)]) {
[self.delegate performSelector:#selector(dismissAndPush:) withObject:VC2];
}
}];
In VC1:
- (void)dismissAndPush:(UIViewController *)vc {
[self.navigationController pushViewController:vc animated:NO];
}
Please help to understand this behavior. Where is my mistake?
From Apple Documentation:
The presenting view controller is responsible for dismissing the view
controller it presented.
So, VC1 should be dismissing the ModalVC, try to do this
ModalVC on click:
if ([self.delegate respondsToSelector:#selector(dismissAndPush:)]) {
[self.delegate performSelector:#selector(dismissAndPush:) withObject:VC2];
}
In VC1:
- (void)dismissAndPush:(UIViewController *)vc {
[self dismissViewControllerAnimated:YES completion:^{
[self.navigationController pushViewController:vc animated:NO];
}];
}
Error has been in other. If Im right understand: some animations before dismissing presented view controller are blocking animations in navigation stack. I solved this problem with 2 ways:
1) deleteting or set right animations before dismissing
2) use setViewControllers in navigation controller (I select it)
- (void)dismissAndPush:(UIViewController *)vc {
[self dismissViewControllerAnimated:NO completion:^{
NSMutableArray *mutableControllers = [NSMutableArray arrayWithArray:self.navigationController.viewControllers];
NSArray *controllers = [mutableControllers arrayByAddingObject:vc];
[self.navigationController setViewControllers:controllers animated:NO];
}];
}

Removing ViewController after showing modally a second ViewController

Guys in my app I have some code in the app delegate method application:didFinishLaunchingWithOptions: that determines if the initial View Controller should be the LoginViewController or the MainViewController.
If the LoginViewController is showed first and the user logs in successfully I show the MainViewController modally with this piece of code:
UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
FSMainViewController *vc = (MainViewController *)[storyBoard instantiateViewControllerWithIdentifier:#"MainViewController"];
vc.loginViewController = self;
[self presentViewController:vc animated:YES completion:nil];
What I want to do next, after the MainController is showed on the screen, is remove the LoginViewController from memory so in the viewWillApper:animated: method of the MainViewController I use this code to remove (or at least try to) the LoginViewController:
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
if (self.loginViewController) {
[self.loginViewController dismissViewControllerAnimated:NO completion:nil];
}
}
Problem is that this code leads to strange behaviors like the MainViewController being removed from the screen and this error message showing up in the console.
Unbalanced calls to begin/end appearance transitions for <LoginViewController: 0xb06e350>
I also tried calling [self dismissViewControllerAnimated:NO completion:nil] in the completion block of the presentViewController:animated:completion method but still no luck, it didn't work.
What am I doing wrong? How can I remove from memory the underlying LoginViewController when the MainViewController is presented modally?
Don't present your main view controller if you want the login controller to go away, just make it the window's root view controller.
UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
FSMainViewController *vc = (MainViewController *)[storyBoard instantiateViewControllerWithIdentifier:#"MainViewController"];
Self.window.rootViewController = VC;
You can't dismissViewController after presenting another one on it or its presentingViewController. At here, you should dismiss LoginViewController first, then present MainViewController.
Otherwise, if you'd like pushViewController, you can call [self.navigationController setViewControllers: animated:] to remove LoginViewController.
If you think presentingViewController is just what you want, try something like this in application:didFinishLaunchingWithOptions:
if (self.loginViewController) { //Define loginViewController in appDelegate.h
[self dismissViewControllerAnimated:NO completion:^{
[self presentViewController:mainViewController animated:YES completion:nil];
}];
}
else{
[self presentViewController:mainViewController animated:YES completion:nil];
}

pushing UIViewController without Navigation Controller

I was using that method for pushing another UIViewController in if condition :
initViewController *MW = [initViewController alloc];
MW = [self.storyboard instantiateViewControllerWithIdentifier:#"init"];
[self.navigationController pushViewController:MW animated:YES];
Now i've changed my architecture and i just removed my Navigation controller. That's why , these steps will not help me any longer due to no NavigationController exist. Now how can i push another ViewController without pressing button -(IBAction) . I just wanted to use it in Storyboard.
Regards.
FYI : without UINavigationController You can't push to another Controller . You can produce a Controller using
PresentViewController
[self presentViewController:objPortrit animated:YES completion:^{ }];
For Ex:
initViewController *MW = [initViewController alloc];
MW = [self.storyboard instantiateViewControllerWithIdentifier:#"init"];
[self presentViewController:MW animated:YES completion:^{
}];
EDIT:
For your comment :
after producing the ViewController with PresentViewController, You need to dismiss it to produce another ViewController .
You can get over from this , something like this in their respective ViewController Use his method. :
-(void)viewDidDisappear {
[self dismissModalViewControllerAnimated:YES];
}

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