Receive a ViewDidUnload message through UINavigationControllerDelegate - ios

DetailViewController <-> MasterViewController <-> ViewController
At the moment I solve my problem by having a variable in the ViewController class point to the DetailViewController so that I can perform a method when the DONE button in ViewController is pressed.
- (void)doneButtonPressed {
[self.detailViewController method];
}
What I want to do is to have the ViewController report to DetailViewController when it unloads, so that DetailViewController can perform the method itself.
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
[[self.navigationController delegate] performSelector:#selector(method)];
}
What I have tried is to have the MasterViewController set the ViewControllers delegate to DetailViewController with this code, when it is pushed:
ViewController *ViewController = [[ViewController alloc] init];
ViewController.navigationController.delegate = self.detailViewController;
[self.navigationController pushViewController:ViewController animated:YES];
UINavigationControllerDelegate has been set in DetailViewController.
What am I doing wrong?

My question was badly formulated.
The answer is in the documentation:
View Controller Programming Guide for iOS
-> Modal View Controllers
Dismissing a Modal View Controller
http://developer.apple.com/library/ios/featuredarticles/ViewControllerPGforiPhoneOS/ModalViewControllers/ModalViewControllers.html#//apple_ref/doc/uid/TP40007457-CH111-SW14

Related

iOS: SWRevealViewController revealToggle is been call but doesn't do nothing

I'm trying to implement SWRevealViewController on this scenario:
From my main viewController:
-(void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:YES];
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
SWRevealViewController *SWR = [storyboard instantiateViewControllerWithIdentifier:#"SWRevealViewController"];
[self presentViewController:SWR animated:YES completion:nil];
}
From my green view controller:
-(void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:YES];
self.reveal = [[SWRevealViewController alloc] init];
self.reveal.delegate = self;
self.menu.target = self;
self.menu.action = #selector(revealToggleAction:);
[self.view addGestureRecognizer:self.reveal.panGestureRecognizer];
NSLog(#"viewDidLoad");
}
-(void)revealToggleAction:(id)sender
{
[self.reveal revealToggle:self];
}
The revealToggle action is been call but doesn't do anything. It doesn't load the rear view controller. Any of you knows this happening or what I'm doing wrong?
Assuming that you are showing the side bar menu from right side.
First Embed your first view controller to navigation controller, then in your first view controller viewdidload() or viewDidAppear method add below mentioned code i.e.
//this is your side menu view controller.
UIViewController *sideMenuController =
[self.storyboard instantiateViewControllerWithIdentifier:#"YourSideMenuIdentifier"];
//this is the navigation controller embed to your green view controller.
UINavigationController *nc1 =
(UINavigationController *)[self.storyboard instantiateViewControllerWithIdentifier:#"YourNavigationControllerIdentifier"];
//This is your reveal view Controller.
SWRevealViewController *revealViewController =
[[SWRevealViewController alloc]initWithRightViewController:sideMenuController frontViewController:nc1];
[self.navigationController pushViewController:revealViewController animated:YES];
[self.navigationController setNavigationBarHidden:YES];
This will navigate to Controller i.e Green View Controller.
then in your green view controller viewdidload() or viewDidAppear method add below mentioned code i.e.
//GreenViewController.h file
#interface GreenViewController : UIViewController
#property (weak, nonatomic) IBOutlet UIBarButtonItem *sideBarItem;
#end
//Your GreenViewController.m file
_sideBarItem.target = self.revealViewController;
_sideBarItem.action = #selector(rightRevealToggle:);
SWRevealViewController *revealController = [self revealViewController];
[self.view addGestureRecognizer:revealController.panGestureRecognizer];
Note: For more details, check below mentioned link
http://www.appcoda.com/ios-programming-sidebar-navigation-menu/
You need set SWRevealViewController is the initial view controller.
You are creating a new instance of SWRevealViewController.
I think if you set the self.reveal to self.revealViewController it will work.

nil delegate in modal view after presentViewController.

My first view in the viewDidLoad has the following code
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"Dialpad" bundle:nil];
self.vc = [sb instantiateViewControllerWithIdentifier:#"DialpadBoard"];
self.vc.delegate = self;
The header file contains the definition of the view controller
#property (nonatomic, retain) DialpadTableViewController *vc;
after catching an event the view loads a new modal view
- (void)handleEvent:(UIGestureRecognizer*)recognizer {
[self presentViewController:self.vc animated:YES completion:NULL];
}
The view also contains the method to dismiss the modal view:
- (void) dialpadControllerDidCancel:(SearchDialpadTableViewController *)controller {
[self dismissViewControllerAnimated:YES completion:nil];
}
The last method never gets called.
The problem is that the modal view when it is loaded has nil self.delegate. The new modal view is loaded from the storyboard as seen below. Why the delegate is nil? I cannot how a segue since the view is in another storyboard.
you can try this
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"Dialpad" bundle:nil];
UINavigationController *nav= [sb instantiateViewControllerWithIdentifier:#"DialpadBoard"];
((SearchDialpadTableViewController *)[nav viewControllers][0]).delegate = self;
[self presentViewController:nav animated:YES completion:NULL];
Since we have the nav let's take the first controller and assign the delegate
the trick ;)
((SearchDialpadTableViewController *)[nav viewControllers][0]).delegate = self;
Does SearchDialpadTableViewController define a delegate protocol and does it have a property that is specific to that protocol?
The header for that file should look something like:
#protocol ViewControllerDelegateProtocol <NSObject>
- (void)dialpadControllerDidCancel:(SearchDialpadTableViewController *)controller;
#end
#interface ViewController : UIViewController
#property (weak, nonatomic) id<ViewControllerDelegateProtocol> searchPadDelegate;
#end
Then when the user taps Done which is I'm assuming what you're trying to do (send a delegate message when that happens). You would write something like
- (IBAction)donePressed:(id)sender
{
if ([self.searchPadDelegate respondsToSelector:#selector(dialpadControllerDidCancel)]) {
[self.searchPadDelegate dialpadControllerDidCancel:self];
}
}
you must be certain, that self.vc is a class, that you expected. It can be also NavigationController

How to display a view?

I'm new to iOS development.
I have a ViewController ViewController with a button. When the user presses that button, I want to switch the view to RegisterViewController.
ViewController.m contains following code:
#import "ViewController.h"
#import "RegisterViewController.h"
#interface ViewController ()
#end
#implementation ViewController
#synthesize registerViewButton;
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)registerViewButtonClick:(id)sender {
NSLog(#"registerViewButtonClick called");
RegisterViewController* controller = [[RegisterViewController alloc] init];
[self.navigationController pushViewController:controller animated:YES];
}
#end
According the debug output, method registerViewButtonClick is actually called, when I press the button.
But the view represented by RegisterViewController doesn't appear.
The code of the application is available here.
What do I need to change in order for the RegisterViewController's view to become visible, when the button is pressed?
I ran your code and found that there is no navigation controller implemented in your code but you are trying to push the registerViewController. Try to present the viewcontroller like below:
[self presentViewController:controller animated:YES completion:nil];
instead of
[self.navigationController pushViewController:controller animated:YES];
The pushViewController works only when there is a UINavigationController. As per the documentation, The UINavigationController class implements a specialized view controller that manages the navigation of hierarchical content. Since, there is no UINavigationController in your code (self.navigationController is nil in this case), nothing happens when you try to push the viewController.
UINavigationController also comes handy when you want to maintain a stack of viewControllers wherein you can push or pop as per the need. This also gives you 'Back' button automatically. If your need is just to present a viewcontroller, then presentViewController: can be the right option.
If you want to present then no need of UINavigationalController.
But for pushing UINavigationalController is must .
In Storyboard, you have to add one UINavigationalController.
In Button Actions initialise the VC correctly with nib Name.
RegisterViewController* controller = [[RegisterViewController alloc] initWithNibName:#"RegisterViewController" bundle:nil];
[self.navigationController pushViewController:controller animated:YES];
You might need to initialize the UIViewController with the nib name..
like this
RegisterViewController* controller = [[RegisterViewController alloc] initWithNibName:#"RegisterViewController" bundle:nil];
RegisterViewController *news=[[RegisterViewController alloc] initWithNibName:#"RegisterViewController" bundle:nil];
[self.navigationController pushViewController:news animated:YES];
[news release];
If you are using storyboards then you need to get your view controller from the storyboard like
RegisterViewController *viewController = (RegisterViewController*)[[UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil] instantiateViewControllerWithIdentifier:#"vc-identifier"];
Replace vc-identifier with whatever you have given as the identifier in storyboards and replace MainStoryboard with the name of your storybaord.
then pass it into your navigation controller like you are already doing, that is as long as your navigation controller isn't nil
[self.navigationController pushViewController:controller animated:YES];
Just been told that you aren't using storyboards, I was unable to download your link because of my location so I gave a solution with storyboards. My recommendation would be to move to using storyboards.
Will leave this here as it may help others who are having the same problem but are using storyboards

Delegation in Xcode

When the user pressed an 'add' button a modal view pops up for them to enter information. I have a 'cancel' button in the top left of a navigation bar and I want it to dismiss the current view controller when it is pressed. How do I set an object as the class's delegate? I understand creating protocols and implementing its methods but I cannot seem to make the delegate be set. When running the debugger my [self delegate] in the 'add' view controller is always nil.
Are you spawning the modal viewController through a segue set up in your Storyboard? If so, then in the prepareForSegue: method you would set the delegate there.
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([identifier isEqualToString:#"userGuideSegue_home"]){
UserGuideViewController* vc = segue.destinationViewController;
[[segue destinationViewController] setDelegate:self];
}
}
On the other hand, if you are setting up the modal viewController entirely through code, then you would create an instance of the modal viewController then set it's delegate.
- (void)showModelView:(NSString*)viewName
{
// code ripped out of project so a bit specific
if ([viewName isEqualToString:#"userGuide_name"]) {
modalViewController = (UserGuideViewController * )
[[UIStoryboard storyboardWithName:#"MainStoryboard_iPhone" bundle:NULL]
instantiateViewControllerWithIdentifier:#"UserGuide"];
}
modalViewController.delegate = self;
modalViewController.modalPresentationStyle = UIModalPresentationFormSheet;
modalViewController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
modalViewController.view.frame = [[UIScreen mainScreen] applicationFrame];;
[self presentViewController:modalViewController
animated:YES
completion:^{
//put your code here
}];
}
Of course all this assumes you have defined a delegate property on your modal viewController.
If you created the view in IB, Control-drag the button into the ViewController's header file and add an IBOutlet. Inside of that method in the .m file you can
[self dismissModalViewControllerAnimated:YES];
alternatively you can create the button programmatically:
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:#selector(processCancel:)];
-(void)processCancel:(UIBarButtonItem *)item{
[self dismissModalViewControllerAnimated:YES];
}
#interface MyViewController : UIViewController {
id delegate;
}
#property (nonatomic,retain) id delegate;
#synthesize delegate;
This should do the job, you can now use [MyViewController setDelegate:self] before showing the modal view and call [[self delegate] dismissModalViewControllerAnimated:YES] in the cancel button tapped event in MyViewController

iOS - Weird navigation problem?

I have 3 UIViewControllers in my UINavigationController.
At some points I want to go to rootViewController and from there navigate to a new UIViewController, and it doesn't aeem to work.
Any suggestions?
- (IBAction)goToRootAndNavigateToViewController
{
[self.navigationController popToRootViewControllerAnimated:YES];
MyViewController *mvc = [[MyViewController alloc] init];
[self.navigationController pushViewController:mvc animated:YES];
[mvc release];
//This takes me to the rootViewController but it doesn't navigate to MyViewController
}
Trying to use performSelector:WithDelay:
- (void)goToRootAndNavigateToViewController
{
[self.navigationController popToRootViewControllerAnimated:YES];
[self performSelector:#selector(doSomething) withObject:nil afterDelay:10];
}
- (void)doSomething
{
MyViewController *mvc = [[MyViewController alloc] init];
[self.navigationController pushViewController:mvc animated:YES];
[mvc release];
}
I believe the popToRootViewController takes up the full NSRunLoop.
You would need to push your next view controller with a separate function using something like performSelector:withObject:afterDelay.
or you could always just do a [self.navigationController setViewControllers:] call to set them manually
You need to push your mvc controller when the animation is complete. Try calling it once the first animation is done (e.g. in - (void)viewDidAppear:(BOOL)animated)
I don't know why you are facing this problem, but one solution you could try is to push the new view controller in your root view controller's -viewDidAppear: method.
I guess it has to do with your current viewcontroller using - (IBAction)goToRootAndNavigateToViewController, is somehow losing its control once being popped. Thus, making consecutive statements to be not working.
If I were you, I would make sure pushing MyViewController instance is done always at rootViewController of your choice, not from the current viewcontroller which is going to be popped from UINavigationController and possibly to be released and deallocated.
Probably, you may want to add delegate method implementation for, such as - (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated in your rootViewController
- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
// Check the right condition for pushing MyViewController...
// if it's YES...
MyViewController *mvc = [[MyViewController alloc] init];
[self.navigationController pushViewController:mvc animated:YES];
[mvc release];
}
In this implementation, you may push MyViewController instance. One thing you have to do beforehand is using some kind of conditional flag, which will make sure the situation is correct for popToRootViewController then push MyViewController

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