Switching between view controllers - ios

I have three view controllers. I used the flipsideproject template and then added another view controller.
There is a button on the first view controller that goes to the second view controller. There is a button on the second view controller that goes back to the first one. When switching between the first and second, those buttons always work.
It is the same situation with the second and third view controller. When I try to transfer between the first to second to third and then back to first, it does not work.
(1-->2-->3-->2-/->1) My poorly drawn diagram depicts the situation.
I had all of the back buttons connected to the back IBAction, which I thought was the problem. I then made another IBAction, but it has not fixed the problem.
1st view controller = MainViewController
2nd VC = FlipSideViewController
3rd VC = ChooseAlarmSound
This is for going 2->1 (this is the problem I think. It sometimes works)
- (IBAction)done:(id)sender
{
[self.delegate flipsideViewControllerDidFinish:self];
}
This is for going 2->3
- (IBAction)chooseSound:(id)sender
{
ChooseAlarmSound *controller = [[[ChooseAlarmSound alloc] initWithNibName:#"ChooseAlarmSound" bundle:nil] autorelease];
controller.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentModalViewController:controller animated:YES];
}
This is for going 3->2
- (IBAction)goBack:(id)sender
{
FlipsideViewController *controller = [[[FlipsideViewController alloc] initWithNibName:#"FlipsideViewController" bundle:nil] autorelease];
controller.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[self presentModalViewController:controller animated:YES];
}

You presented your 3rd VC (going from 2 to 3) using modalviewcontroller. But then you tried to go back to 2nd VC (from 3rd to 2nd) using another modalVC. That will not let you go back to the previous instance of 2nd VC. You need to use dismissmodalviewcontrolleranimated method to do this. Checkout Apple website on modalviewcontroller class reference for detail info on this.

As suggested by user523234, all you need to do is call
[self dismissModalViewControllerAnimated:YES]
in the
- (IBAction)goBack:(id)sender
method of the 3rd view controller, instead of what you're doing, which is creating another instance of the 2nd view controller and presenting it.
The reason it's not working now, is because when you press the done button in the 2nd view controller it calls
- (IBAction)done:(id)sender
{
[self.delegate flipsideViewControllerDidFinish:self];
}
which is sending a message the 2nd view controller's delegate, which you haven't set in the case where you're going from 3->2.

Related

Not able to navigate to another UIViewController programmatically iOS

I am trying to navigate to "Home" view controller and for this I have written the following code in the ContainerViewController. But once the code executes, the application hangs and it show 100% CPU usage. Please help.
- (IBAction) home:(UIButton *)sender
{
HomeViewController *homeViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"HomeViewController"];
[self.navigationController pushViewController:homeViewController animated:YES];
//[self presentViewController:homeViewController animated:YES completion:nil];
}
I have a question for you
1-If You want to push SecondViewController on to FirstViewController then your code is good enough
2-If you have a containerview in firstViewController and you want to add SecondViewcontroller's view to firstViewController
then use this code
UIViewController*vc1 = [[test1 alloc]initWithNibName:#"SecondViewController" bundle:nil];
//add to the container vc which is self
[self addChildViewController:vc1];
//the entry view (will be removed from it superview later by the api)
[self.view addSubview:vc1.view];
I think you want an unwind segue here. In your first view controller add :
- (IBAction)unwindToFirstViewController:(UIStoryboardSegue*)sender
{
}
You then need to hook up each of your view controllers home button to the green Exit button at the bottom of the view controller, choosing the unwindToMainMenu option. This will then take you back to the first view controller when pressed.
Have you tried popping the current view?
navigationController?.popViewControllerAnimated(true)
or just popping to root?
navigationController?.popToRootViewControllerAnimated(true)
or setting a new stack?
navigationController?.setViewControllers(homeViewController, animated: true)
The code is in Swift but it would work the same in ObjectiveC

Going from a Storyboard to Nib and back again

Ok, I'm still pretty new; so, please bear with me.
I'm creating a custom app for a friend that displays a list of work orders in a table view. Clicking on a work order brings them to a detail view. In the detail view, there is a button that uses a push to present another screen called completion view. From the completion view, they click a button that uses the following code to present a nib for signature capture.
SigScreenViewController *sigScreenViewController=[[SigScreenViewController alloc] initWithNibName:#"ViewController_iPhone" bundle:nil];
[self presentViewController:sigScreenViewController animated:YES completion:nil];
The signature screen uses: https://github.com/jcmontiel/SignatureViewExample for capturing the signature and does it well. I have a button that completes the transaction and sends it back to the table view list.
My problem is that I cannot create a button that will return me to the completion view in the storyboard.
I've tried the following in a button:
[self dismissViewControllerAnimated:YES completion:nil];
or
[self.navigationController popViewControllerAnimated:YES];
I'm open for any suggestions on how I can do it.
Thanks in advance!
Have you tried having the UIViewControllers embedded in a navigation controller ?
Are you pushing from a UIViewController in UIStoryboard to a NIB file?
If so check out this sample project that pushes from storyboard to a NIB:
// in a navigation controller
// to load/push to new controller use this code
// this will be next screen
DetailsViewController *detailsViewController = [[DetailsViewController alloc ]init];
[self.navigationController pushViewController:detailsViewController animated:YES];
// to go back or pop controller use this
// now it will send back to parent screen
[self.navigationController popViewControllerAnimated:YES];

How to switch between view controllers and get rid of the previous one

In android, switching between activities, is fairly straightforward
you call
Intent intent = new Intent(this,NextActivity.class); <- define the next activity
startActivity(intent); <- start the next activity
finish(); < -get rid of the current activity
now in iOS i know how to do this:
UIViewController *nextviewcontroller = [[UIViewController alloc]initWithNibName:#"nextvc" bundle:nil];
[self presentViewcontroller:nextviewcontroller animated:YES completion:nil];
How do I get rid of the current view controller? so that currentviewcontroller dies after presenting nextviewcontroller ?
[self dismissViewController:YES]; doesnt seem to do the trick
the lifecycle methods viewWillDisappear and viewDidDisappear are called even if I don't call [self dismissViewController:YES];
i want "currentviewcontroller" to be removed from the memory, and from the viewcontroller stack, so that clicking "back" in "nextviewcontroller" will go to some thirdviewcontroller that was before currentviewcontroller
In iOS is different, since there's no concept of Activity and everything is more focused on the app itself (in Android you can mix activities from different apps). Therefore, there's no concept of "view controller stack".
The most similar concept is the "navigation stack" of navigation controllers, where you actually push and pop new view controller into some kind of linear navigation. A navigation bar is automatically created and populated with back buttons.
presentViewController will show your view controller modally upon the current one, but you can't thrash the presenting one since it's holding and containing ("defining context") the new one.
If you use a navigation controller for your navigation hierarchy (I don't know if you can), you can override the back button and use something like
UIViewController * prev = self.navigationController.viewControllers[self.navigationController.viewControllers.count -2 ]
[self.navigationController popToViewController:prev animated:YES]
With a modal view controller, you may try something like (I haven't tried but it may work)
[self.presentingViewController.navigationController popViewControllerAnimated:YES]
You should write one of these code into the target action of your close button.
iOS doesn't maintain a global stack of controllers in the way that Android does. Each app shows a controller at its root, and that one is responsible for showing the other controllers in the app. Controllers can display other controllers modally using presentViewcontroller:animated:completion: but the presenting controller remains underneath the presented one.
If your current controller is the root controller, then instead of using presentViewcontroller:animated:completion: you'd just do this:
self.view.window.rootViewController = nextViewController;
It's very common for the root controller to be a UINavigationController, which does manage a stack of controllers. If that is the case, and if your current controller is at the top of the stack, you'd do this:
[self.navigationController popViewControllerAnimated:NO];
[self.navigationController pushViewController:nextViewController animated:YES];
If your setup is different, you'd do something different; it's hard to say what without knowing more. But it's most likely that you'd be in the UINavigationController case.
In the viewDidAppear of your nextviewcontroller you could add :
-(void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
NSArray *controllers = self.navigationController.viewControllers;
NSMutableArray *newViewControllers = [NSMutableArray arrayWithArray:controllers];
[newViewControllers removeObjectAtIndex:[controllers count]-2];
self.navigationController.viewControllers = newViewControllers;
}
There is nothing available like this in iOS but you can achieve it doing something like below
NSArray *viewControllers=[self.navigationController viewControllers];
NSMutableArray *newControllers=[[NSMutableArray alloc] init];
for(int i=[viewControllers indexOfObject:self];i<viewControllers.count;i++){
[newControllers addObject:[viewControllers objectAtIndex:i]];
}
[self.navigationController setViewControllers:[[NSArray alloc] initWithArray:newControllers]];
I have tried the method of storing all the view controllers in an array but it didn't work for me . When you try popViewController it will move to the View Controller which is last in the stack.
You can make 2 navigation controllers and switch between them and also switch between the view controllers of a particular Navigation Controller.
For eg.
You can switch between 2 Navigation Controller using the following code:
FirstNavController *fisrtView=[storyboard instantiateViewControllerWithIdentifier:#"firstnavcontroller"];
self.window.rootViewController = firstView;
}else{
SecondNavController *secondView=[storyboard instantiateViewControllerWithIdentifier:#"loginnavcontroller"];
self.window.rootViewController = secondView;
}
If your FirstNavController has 2 ViewControllers then you can switch between them using pushViewController
SecondViewController *sc = [self.storyboard instantiateViewControllerWithIdentifier:#"secondviewcontroller"];
[[self navigationController] pushViewController:sc animated:YES];
and popViewController
[self.navigationController popViewControllerAnimated:YES];

start 1 view controller 2 buttons that lead to 2 different view controllers

I have the first ViewController that has 2 buttons on it. One to go to ViewController1 when clicked and the other to go to ViewController2 when clicked. When i click the first button it takes me to ViewController1 but when i click the second button it goes to a black screen and gives the warning:
Warning: Attempt to present on while a presentation is in progress!
What am I doing wrong?
Here is my code:
-(IBAction)goToYourClosetViewController: (id)sender{
YourClosetViewController *closet = [[YourClosetViewController alloc] initWithNibName:nil bundle:nil];
[self presentViewController:closet animated:YES completion:NULL];
}
-(IBAction)goToPlanOutfitViewController: (id)sender{
PlanOutfitViewController *planOutfit = [[PlanOutfitViewController alloc] initWithNibName:nil bundle:nil];
[self presentViewController:planOutfit animated:YES completion:NULL];
}
Are you pressing the first button and then the second button in rapid succession by any chance?
If that's it then you need to disable your buttons while the modal presentation is in progress, and re-enable them in your completion blocks.
If not, then how are you displaying the first view controller? (The one that contains these 2 buttons)
You are probably trying open the second view controller before you close the first view controller. That's the kind of error message in such cases.
When you go back to your initial view controller from either first or second view controller, do this:
[FirstViewControllerInstance dismissModalViewControllerAnimated:YES];

IOS: dismiss two viewController

I have three viewController
First, Second and Third
from Second to open Third I use
Third *third = [[Third alloc]initWithNibName:#"Third" bundle:nil];
[self presentModalViewController:third animated:YES];
[third release];
Now I want return from third to first; then I set in viewDidAppear in second this code:
[self dismissModalViewControllerAnimated:NO];
but for 1 second I see Second and I don't want watch it...how can I do?
You need to dismiss third view controller first and then second Viewcontroller. Do the following code when you want to go first view controller.
-(void)goToFirstView{
UIViewController *vc = [self parentViewController];
// UIViewController *vc = [self presentingViewController]; //ios 5 or later
[self dismissModalViewControllerAnimated:NO];
[vc dismissModalViewControllerAnimated:YES];
}
How is the Third modal view being dismissed in the first place? Perhaps by the user touching a 'Done' button? If so, it is in the handler for the button that you want to dismiss both.
You can dismiss both as:
[self dismissModalViewControllerAnimated: YES];
[self.presentingViewController dismissModalViewControllerAnimated: NO];
This happens coz viewDidAppear is called everytime before the view appears so as soon as it appears you dismiss it and it disappears..
I don't think what u are trying to do can be achieved with modalViewControllers...
instead use a navigationController and keep adding your viewcontrollers onto the stack and when you want to goto the First view controller just call
[self.navigationController popToRootViewControllerAnimated:YES];
EDIT:
just thought of it this can be achieved by using delegation.. you make second the delegate of third and as soon you dismiss the thirdviecontroller send the delegate a message.In this message call [self dismissModalViewControllerAnimated:NO];..
and you are done.. (pretty easy if you know delegation.)

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