Dismissing view controller to reveal desired one on the backside - ios

Suppose i have 3 view controllers. I initiate vc1 in vc0 and then vc2 in vc1. Now i want vc2 to be dismissed and after that only vc0 should be shown behind it. How's that possible? I read something about delegate declaration. But couldn't understand.
I have UISegmentcontrol where i'm displaying a controller from storyboard like - vc0 = [self.storyboard instantiateViewControllerWithIdentifier=#"vc0"]; and making it a subview of it [self.view addSubview:vc0.view]; Vc0 is a tableView, which has a detailcontroller to be presented. When i tap on a cell, it shows detailview, but actual segmentcontrol.view is lost when detailview is dismissed.
An example would be awesome.
PS: I'm not using segue for the viewControllers. Instead, i'm using presentModalViewController and dismissModalViewController.

In iOS 5 you need to do
[self.presentingViewController.presentingViewController dismissModalViewControllerAnimated:YES]
As of iOS 6 dismissModalViewControllerAnimated: is deprecated.
You need to call
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:^{ // Do something on completion}]
//If you want to perform something while going through views or other wise keep completion to nil as shown in below code.
or
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:nil];
or
[self.parentViewController.parentViewController dismissModalViewControllerAnimated:YES];

Related

Dismiss Modal View Controller and Simultaneously Segue from Sending to Different View Controller in IOS

I launch a modal view controller VCM embedded in a Navigation controller from VC1.
The modal VC has a button to go to another View Controller, VC2.
if the user presses the button to go to VC2, I need to simultaneously dismiss the modal and also change the sending from VC1 to VC2. (It's important to dismiss the modal to get rid of it, so I don't have VCs accumulating on the stack.)
Here is the action method in the modal attached to the VC2 button.
- (IBAction)VC2ButtonPressed:(id)sender {
[self dismissViewControllerAnimated:true completion:nil];
//Above line works fine
[VC1 performSegueWithIdentifier:#"showVC2" sender:VC1];//No known class method error
}
I can dismiss the modal without any problem (first line) but can't figure out how to simultaneously segue to VC2. There is a storyboard segue in VC1 named 'showVC2' for what it's worth. I do not have any relevant class methods currently in the sending VC. Should I create a special class method? Or how can I invoke a method in the VC that launched the modal.
Edit:
I also tried:
[self.presentingViewController performSegueWithIdentifier:#"showVC2" sender:self];
This compiles but gives runtime error () has no segue with identifier 'showVC2''
I think this is because VC2 is embedded in a tabbarcontroller.
Edit2:
I tried putting code in completion handler as suggested by #Oscar but while code gets fired, VC2 does not load
[self dismissViewControllerAnimated:YES completion:^{
[self gotoVC2];
}];
new method
-(void)gotoVC2 {
LogDebug(#"gotoVC2 called");//DOES log to console
UIStoryboard *storyBoard = self.storyboard;
IDFeedVC *VC2 =
[storyBoard instantiateViewControllerWithIdentifier:#"vc2"];
[self presentViewController:VC2 animated:YES completion: nil];
}
Thanks for any ideas.

All the presented view controllers are not dismissed

I have a firstViewController that I display with
[self.navigationController pushViewController:firstViewController animated:true];
Then when a button in this first VC is clicked, I present a second one:
[self presentViewController:secondViewController animated:true completion:nil];
And from this second one I present the third VC as a modal:
[thirdVC modalPresentationStyle];
[thirdVC setModalPresentationStyle:UIModalPresentationOverCurrentContext];
[self presentViewController:thirdVC animated:true completion:nil];
The problem is that I want to display the firstVC when the validate button of the last VC is clicked. So I have to dismiss the third and the second one. I tried this in the validateAction (in the third VC):
[[self parentViewController] dismissViewControllerAnimated:true completion:nil];
[self dismissViewControllerAnimated:true completion:nil];
But the result is that the thirdVC (the modal one) is dismissed, and from the debugger I can see that the firstVC is covered by the secondVC.
How can I dismiss the second and the third VC at the same time in order to return to the first one?
NOTE: I want to push the firstVC after the dismiss of the others because I have to reload the data (in the fristVC viewDidLoad)
From Apple's Documentation:
The presenting view controller is responsible for dismissing the view controller it presented. If you call this method on the presented view controller itself, UIKit asks the presenting view controller to handle the dismissal.
In other words, the third viewController asks the second viewController to dismiss its presented viewController, which is the third one. Then the third viewController tries to dismiss itself, causing UIKit to ask the second viewController to dismiss the third one once more.
You will have to go one layer up and ask the first viewController to dismiss its presented view controller.
It is good practice that the third viewController does not know anything about the presentation hierarchy. You can use delegation to tell the first viewController that the task is finished. An exit segue is a very nice alternative if you use storyboards.
You only have to call -dismissViewControllerAnimated:completion: once if you address the first viewController:
If you present several view controllers in succession, thus building a stack of presented view controllers, calling this method on a view controller lower in the stack dismisses its immediate child view controller and all view controllers above that child on the stack.

`dismissViewControllerAnimated: completion:" dismisses keyboard and not VC

I have a ViewController with an UISearchController inside (with a table view on it). I've added this line on didSelectRowAtIndexPath::
[self dismissViewControllerAnimated:YES completion:nil];
For some reason, the viewController isn't being dismissed and instead, the keyboard is being dismissed (the searchController becomes inactive), to dismiss the viewController I have to reselect a cell on the table (and then didSelectRowAtIndexPath: is being called twice).
Any idea why is it happening?
Thank you!
This is probably happening because UISearchController inherits from UIViewController and therefore the controller being dismissed in didSelectRow is actually the search controller.
Perhaps simply try dismissing twice so that it removes the search controller followed by your custom view controller:
[self dismissViewControllerAnimated:YES completion:nil];
[self dismissViewControllerAnimated:YES completion:nil];
Try to resigning keyboard first and then dismiss vc.

Pop THE RootViewController

I am developing an app that as first viewcontroller has an UIViewController.
This controller pushes a NavigationViewController that contains other controllers.
Now I need to pop the RootViewController of the NavigationController to go back to the initial UIViewController.
I tried with
[self dismissViewControllerAnimated:YES completion:nil];
and the app crashes("Tread1:EXC_BAD_ACCESS(code=1, address= ......)").
I tried with
[self.navigationController popViewControllerAnimated:YES];
and nothing happens.
The initial UIViewController calls
[self performSegueWithIdentifier:#"MyIdentifier" sender:self];
In the UIBuilder the segue is of type "Show(e.g. Push)"
Then I have a NavigationViewcontroller that contains the RootViewController and another Viewcontroller.
What I am trying to achieve is to go back to the first viewcontroller (the one outside the navigationcontroller) from the RootViewController. So I should have the navigationcontroller there.
What am I missing?
Apparently I had a couple of GestureRecognizer still in place that were causing the crash of the app.
The right method was:
[self dismissViewControllerAnimated:YES completion:nil];

Dismissing a ViewController lower in the stack does not behave as expected

I'm building a complex app that has kind of a branch in the middle.
At some point in the app, a particular UIViewController is presented, we'll call it mainViewController (shortened mainVC).
The mainVC presents another view controller, by code, using the following code (I strip out parts of it for privacy reasons):
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"SecondaryStoryboard" bundle:secondaryBundle];
SecondViewController *secondVC = [storyboard instantiateInitialViewController];
[self presentViewController:secondVC animated:YES completion:nil];
So the secondVC will later present another view controller, called thirdVC. This is done using a custom segue, set in the storyboard used in the code above, which code looks like this:
#implementation VCCustomPushSegue
- (void)perform {
UIView *sourceView = ((UIViewController *)self.sourceViewController).view;
UIView *destinationView = ((UIViewController *)self.destinationViewController).view;
UIWindow *window = [[[UIApplication sharedApplication] delegate] window];
destinationView.center = CGPointMake(sourceView.center.x + sourceView.frame.size.width, destinationView.center.y);
[window insertSubview:destinationView aboveSubview:sourceView];
[UIView animateWithDuration:0.4
animations:^{
destinationView.center = CGPointMake(sourceView.center.x, destinationView.center.y);
sourceView.center = CGPointMake(0 - sourceView.center.x, destinationView.center.y);
}
completion:^(BOOL finished){
[self.sourceViewController presentViewController:self.destinationViewController animated:NO completion:nil];
}];
}
#end
As you can see this segue presents the destination view controller modally (by the use of presentViewController:) with a custom animation (a slide from right to left).
So basically up to here everything is fine. I present the secondVC with a classic modal animation (slide up from bottom) and present the thirdVC with my custom transition.
But when I want to dismiss the thirdVC, what I want is to go back directly to the mainVC. So I call the following from the thirdVC :
self.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:_animate completion:nil];
That way, I'm calling dismissViewControllerAnimated: directly on mainVC (referenced by self.presentingViewController.presentingViewController), and I'm expecting the thirdVC to be dismissed with an animation, and the secondVC to just disappear without animation.
As Apple says in the UIViewController Class Documentation:
The presenting view controller is responsible for dismissing the view
controller it presented. If you call this method on the presented view
controller itself, it automatically forwards the message to the
presenting view controller.
If you present several view controllers in succession, thus building a
stack of presented view controllers, calling this method on a view
controller lower in the stack dismisses its immediate child view
controller and all view controllers above that child on the stack.
When this happens, only the top-most view is dismissed in an animated
fashion; any intermediate view controllers are simply removed from the
stack. The top-most view is dismissed using its modal transition
style, which may differ from the styles used by other view controllers
lower in the stack.
The issue is that it's not what happens. In my scenario, the thirdVC disappears, and shows the secondVC being dismissed with the classic modal slide to bottom animation.
What am I doing wrong ?
Edit :
So #codeFi's answer is probably working in a classic project, but the problem here is that I'm working on a framework. So mainVC would be in a client app, and the secondVC and thirdVC are in my framework, in a separate storyboard. I don't have access to mainVC in any other way than a reference to it in my code, so unwind segues are unfortunately not an option here.
I've been having this exact same issue, and I've managed to visually work around it by adding a snapshot of the screen as a subview to secondVC.view, like so:
if (self.presentedViewController.presentedViewController) {
[self.presentedViewController.view addSubview:[[UIScreen mainScreen] snapshotViewAfterScreenUpdates:NO]];
}
[self dismissViewControllerAnimated:YES completion:nil];
Not pretty, but it seems to be working.
NOTE: if your secondVC has a navigation bar, you will need to hide the navigation bar in between snapshotting the screen and adding the snapshot as a subview to secondVC, as otherwise the snapshot will appear below the navigation bar, thus seemingly displaying a double navigation bar during the dismissal animation. Code:
if (self.presentedViewController.presentedViewController) {
UIView *snapshot = [[UIScreen mainScreen] snapshotViewAfterScreenUpdates:NO];
[self.presentedViewController.navigationController setNavigationBarHidden:YES animated:NO];
[self.presentedViewController.view addSubview:snapshot];
}
[self dismissViewControllerAnimated:YES completion:nil];
I had the same issue and I've fixed it by using UnwindSegues.
Basically, all you have to do is add an IBAction Unwind Segue method in the ViewController that you want to segue to and then connect in IB the Exit action to your Unwind Segue method.
Example:
Let's say you have three ViewControllers (VC1, VC2, VC3) and you want to go from VC3 to VC1.
Step 1
Add a method to VC1 like the following:
- (IBAction)unwindToVC1:(UIStoryboardSegue*)sender
{
}
Step 2
Go in Interface Builder to VC3 and select it. Then CTRL-drag from your VC icon to Exit icon and select the method you've just added in VC1.
Step 3
While still in IB and with VC3 selected, select your Unwind Segue and in the Attributes Inspector add a Segue Identifier.
Step 4
Go to VC3 where you need to perform your segue (or dismiss the VC) and add the following:
[self performSegueWithIdentifier:#"VC1Segue" sender:self];

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