pushViewController when back from background - ios

When app is back from the background, I want to push my menu viewcontroller from the navigation controller.
To test — NSString returns the title of my Navigation controller so it should work, but it does not.
It always show the view controller.
P.S. I use storyboard.
In AppDelegate.m:
- (void)applicationWillEnterForeground:(UIApplication *)application
{
NSString * test = self.window.rootViewController.title; // return title of navigation controller
MenuViewController *mvc = [[MenuViewController alloc] init];
[(UINavigationController *)self.window.rootViewController pushViewController:mvc animated:NO];
}
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Probably, you should update your UI in - (void)applicationDidBecomeActive:(UIApplication *)application method.
Update.
Also, error is because in your storyboard you present new ViewControllers as Modal, but you should Push them. Then you can return to main menu by calling
[(UINavigationController *)self.window.rootViewController popToRootViewControllerAnimated:NO];
To change presentation style choose segue in your storyboard, choose Attributes Inspector and change style to 'Push'.
Or, if you prefer Modal presentation style, call
[(UINavigationController *)self.window.rootViewController dismissModalViewControllerAnimated:YES];

Related

Dismiss all Detail Views when switching Tabs on TabBarController

My iOS app has:
TabBarController
NavigationController1
TableView1
ViewController1 (Details View)
NavigationController2
TableView2
ViewController2 (Details View)
Behavior:
When the app loads, I see the TableView1.
I select an Item in the table, and it takes me via Show (Push) segue the details view 1.
I switch to the second tab on the bottom, and see TableView2.
I select an item and it takes me to details view 2
I navigate back to first tab, and see details view 1
Desired:
When performing last step, I'd like to dismiss the details view and see the first TableView1, and when switching back to second tab, I want that one to be dismissed and to see the table view.
I've tried different combinations of dismissViewControllerAnimated and popToRootViewControllerAnimated but I just don't seem to figure it out.
MainTabBarController.h
#interface MainTabBarController : UITabBarController <UITabBarControllerDelegate>
MainTabBarController.m
- (void)viewDidLoad {
[super viewDidLoad];
self.delegate = self;
}
...
- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController{
// NSLog Works fine, and displays information in the output
NSLog (#"%# %lu", tabBarController.selectedViewController.title, tabBarController.selectedIndex);
// None of the lines below achieve the desired result
[viewController.navigationController popToRootViewControllerAnimated:YES];
[viewController dismissViewControllerAnimated:YES completion:nil];
[tabBarController.navigationController popToRootViewControllerAnimated:YES];
[tabBarController dismissViewControllerAnimated:YES completion:nil];
}
One option is to make use of the UITabBarControllerDelegate. Listen for changes to the tab selection. Based on the new tab, get the tab's navigation controller and call its popToRootViewControllerAnimated: method.
Update based on the code added to the question:
The problem is with how you try to pop the view controllers. You want this:
- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController{
// NSLog Works fine, and displays information in the output
NSLog (#"%# %lu", tabBarController.selectedViewController.title, tabBarController.selectedIndex);
// If the selected tab's root controller is a navigation controller
// pop to the top view controller in the tab's navigation stack
if ([viewController isKindOfClass:[UINavigationController class]]) {
UINavigationController *nav = (UINavigationController *)viewController;
[nav popToRootViewControllerAnimated:NO];
}
}
Here is a simple solution for this.
Try to implement the following methods of UIViewContorller
- (void)viewWillDisappear:(BOOL)animated; // Called when the view is dismissed, covered or otherwise hidden. Default does nothing
- (void)viewDidDisappear:(BOOL)animated; // Called after the view was dismissed, covered or otherwise hidden. Default does nothing
Go to your detail-1 view controller and implement the method - (void)viewWillDisappear:(BOOL)animated.
Do a pop for that controller.
Same you should do for the detail-2
Here is the code snippet that will help you.
In Appdelegate.m
#interface AppDelegate ()<UITabBarControllerDelegate>
#property(nonatomic, strong) MainTabBarController *rootTabBarController;
#end
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
self.rootTabBarController = [[MainTabBarController alloc]init];
self.rootTabBarController.delegate = self;
self.window.rootViewController = self.rootTabBarController;
[self.window makeKeyAndVisible];
}
TabBarController delegate implementation
-(void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController {
NSUInteger index = [self.rootTabBarController.viewControllers indexOfObject:viewController];
NSLog(#"Index : %lu", (unsigned long)index);
switch (index) {
case 0:
// pop other tab barcontrollers pushed or modal windows
[self.rootTabBarController flushViewControllerStackForIndex:1];
break;
case 1:
[self.rootTabBarController flushViewControllerStackForIndex:0];
break;
default:
break;
}
}
MainTabBarController.m
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
[self setViewControllers:#[
[[UINavigationController alloc] initWithRootViewController:[[FirstViewController alloc]init]],
[[UINavigationController alloc] initWithRootViewController:[[SecondViewController alloc]init]]
] animated:YES];
}
-(void)flushViewControllerStackForIndex:(NSUInteger )index {
[[self.viewControllers objectAtIndex:index] popToRootViewControllerAnimated:NO];
}
Here is screenshot in sequence for the sample I ran.
Here is the Sample code.
That should solve your purpose & is the right approach.
Now you may need to fine tune your own logic in flushViewControllerStackForIndex to check if there is just only controller being pushed on stack or a combination of push & modal. So better try to navigate on the Stack & do-a-dismiss-if-a-modal or do-a-pop-if-a-push.
Hope that helps.
You can directly set the view controllers currently on the navigation stack. All you have to is directly set the viewControllers property of the navigation controllers when switch tabs in the tabbar controller.
Set NavigationController1.viewcontrollers = #[tableView1] when you switch to tab1

Pushing ViewController from app delegate

I am using a storyboard in Xcode 5, which appears as so:
My requirement is to push a ViewController (VIEW1 or VIEW2) into view from the app delegate. Essentially it should not matter what view is presently on the screen -- I would just like to make a ViewController appear when the app delegate picks up an external event.
In order to try and achieve this, I have property references to both the TabBarCtrl-Products and NavCtrl-ProductA in my app delegate.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
_tabBarProducts = [[UIStoryboard storyboardWithName:#"Main" bundle:nil] instantiateViewControllerWithIdentifier:#"sidTabBarProducts"];
NSArray *tabvcs = _tabBarProducts.viewControllers;
for (id controller in tabvcs){
if ([controller isKindOfClass:[VCNavControl_ProductA class]]) {
_navControllerProductA = controller;
break;
}
}
return YES;
}
The app delegate method to push VIEW2 is:
-(void)showVCVIEW2
{
VC_V2 *targetvc = nil;
targetvc = [[UIStoryboard storyboardWithName:#"Main" bundle:nil] instantiateViewControllerWithIdentifier:#"sidView2"];
[[AppDelegate sharedInstance].navControllerProductA pushViewController:targetvc animated:NO];
}
This works OK when VIEW1 is showing at the time showVCVIEW2 is called, however it does not work when ViewCtrl-ProductB is showing. I can see that the new instance of targetvc has been added to the AppDelegate _navControllerProductA's stack, however it does not display.
(Regarding the setting of the the app delegate's rootViewController, I set this to _tabBarProducts after the VC-Splash and VC-Setup ViewCtrls have finished).
I would appreciate very much if anyone can give me an idea on how to achieve this. I suspect my problems stem from having a NavCtrl in a TabBarCtrl, but I do not know a way around this.
Your problem is that the navigation controller you are pushing on is not in the view hierarchy.
You instead could try setting the tabBarController's selected index like this:
[self.tabBarController setSelectedIndex:1];

iOS State restoration and UINavigationController modal views

I am trying to incorporate State Restoration in my app. I have it working fine for the most part, but presenting a navigation controller for a modal view on top of another navigation controller seems challenging.
For testing, I created a new split-view app on the iPad, with navigation controllers for both sides of the split view, and a Master and Detail view controller for each side, the roots of their respective navcontrollers. In the master view, you can click on a button to push a new TestViewController onto the navController stack programatically. I hook up the splitView in the storyboard, add restorationIDs to everything, opt-in to the delegate, provide a restoration class and adhere to the UIViewControllerRestoration protocol for TestViewController (since it's created programmatically) and everything works fine. If I close the app and retort it, it will start the TestViewController pushed onto the master's navcontroller. So far so good.
I then change the button handler to present the TestViewController inside a new UINavigationController, present it onto the master's navigation controller, to show a modal view (instead of pushing it on the nav stack). Now, when I relaunch the app, there is no modal view there anymore. TestModalViewController's viewControllerWithRestorationIdentifierPath:coder: is actually called correctly as before, but the modal view is never presented for some reason.
Here is the code for what I'm talking about
MasterViewController.h:
- (void)pushButton:(id)sender
{
TestModalViewController *test = [[TestModalViewController alloc] initWithNibName:#"TestViewController" bundle:nil];
test.restorationIdentifier = #"testid";
test.restorationClass = [TestModalViewController class];
UINavigationController *modal = [[UINavigationController alloc] initWithRootViewController:test];
modal.modalPresentationStyle = UIModalPresentationFormSheet;
modal.restorationIdentifier = #"ModalTestID";
[self.navigationController presentViewController:modal animated:YES completion:nil];
return;
}
TestModalViewController.m:
+ (UIViewController *) viewControllerWithRestorationIdentifierPath:(NSArray *)identifierComponents coder:(NSCoder *)coder {
TestModalViewController *test = [[TestModalViewController alloc] initWithNibName:#"TestViewController" bundle:nil];
test.restorationClass = [TestModalViewController class];
test.restorationIdentifier = [identifierComponents lastObject];
return test;
}
Perhaps the UINavigationController that is created to display modally is never preserved? Not sure why, because it does have a restorationIdentifier.
Edit:
After further testing, it turns out if I remove the UINavigationController from the the pushButton: code, and present the TestModalViewController instance directly, it gets restored correctly. So something about the UINavigationController being presented from another UINavigationController?
This works (though not what I really want):
- (void)pushButton:(id)sender
{
TestModalViewController *test = [[TestModalViewController alloc] initWithNibName:#"TestViewController" bundle:nil];
test.restorationIdentifier = #"testid";
test.restorationClass = [TestModalViewController class];
//UINavigationController *modal = [[UINavigationController alloc] initWithRootViewController:test];
//modal.modalPresentationStyle = UIModalPresentationFormSheet;
//modal.restorationIdentifier = #"ModalTestID";
[self.navigationController presentViewController:test animated:YES completion:nil];
return;
}
EDIT:
Attached link to test project: dropbox.com/sh/w8herpy2djjl1kw/vw_ZWqimgt
It's basically the Core Data master-detail template; run it on the iPad simulator. The + button in Master invokes the TestModalVC; if you then press the Home button, then kill debugger and launch again, you see the snapshot contains the TestModalVC but when the app is launched, it doesn't get restored
You can either create your own restoration class to handle this, or add the following to your app delegate:
- (UIViewController *)application:(UIApplication *)application viewControllerWithRestorationIdentifierPath:(NSArray *)identifierComponents
coder:(NSCoder *)coder
{
NSString *lastIdentifier = [identifierComponents lastObject];
if ([lastIdentifier isEqualToString:#"ModalTestID"])
{
UINavigationController *nc = [[UINavigationController alloc] init];
nc.restorationIdentifier = #"ModalTestID";
return nc;
}
else if(...) //Other navigation controllers
{
}
return nil;
}
More information in the documentation.

Instantiate UINavigationController on button action

I have simple application with only one main view, which has 'Settings' button, and settings are tree-grouped, so I wand to present them in navigation controller. And I don't want navigationController in main view, because I don't want navigation bar there.
That's why I don't instantiate navigationController in application: didFinishLaunchingWithOptions:. And when I check self.navigationController in 'Settings' button handler, it returns nil.
So I wrote this: (I use ARC)
- (void)doSettings
{
NSLog(#"%#", self.navigationController); // prints nothing
SettingsViewController *settingsViewController = [SettingsViewController alloc] initWithStyle:UITableViewStyleGrouped];
UINavigationController *navigationController = [[UINavigationController alloc] init];
[self.view.window setRootViewController:navigationController];
[navigationController pushViewController:settingsViewController animated:YES];
}
This works, although it pushes settingsViewController without animation (don't know why).
Is this generally the correct way to do - to change rootViewController in the middle of running app?
And if yes - than when I'm done with Settings, I probably need to set rootViewController back to current viewController, as it was before I tapped 'Settings'?
I think you want to create a navigation controller that you will present modally; the following will do:
SettingsViewController* settingsViewController = [[SettingsViewController alloc] initWithStyle:UITableViewStyleGrouped];
UINavigationController *navigationController = [[UINavigationController alloc] init];
[navigationController pushViewController:settingsViewController animated:YES];
[self presentViewController: navigationController animated: YES completion:nil];
where self here is the view controller you want to trigger the modal view controller from.
since you present modally the navigation controller you can dismiss it within the code source of your settingsViewController by accessing its navigation controller:
[self.navigationController dismissViewControllerAnimated:YES completion: nil];
To answer your question setting the rootViewController is not the correct way. Present the new vc modally through the presentViewController method.
A better way is to build the navigation vc and present it over your main vc (not replace your main vc).
- (void)doSettings
{
NSLog(#"%#", self.navigationController); // prints nothing
SettingsViewController *settingsViewController = [SettingsViewController alloc] initWithStyle:UITableViewStyleGrouped];
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController: settingsViewController];
[self presentViewController: navigationController animated:YES completion:^{}];
}
Your main vc might realize (maybe as a delegate) that the settings flow is complete. It can then dismiss the presented navigation controller with:
- (void)dismissViewControllerAnimated:(BOOL)flag completion:(void (^)(void))completion
Alternatively, the setting flow could dismiss itself...
// somewhere in the settings vc or a vc it pushes, when we decide settings are done
self.navigationController dismissViewControllerAnimated:YES completion:^{}];
Have navigation in main view and have below line (which will hide navigation bar)
[[self navigationController] setNavigationBarHidden:YES animated:YES];
(I would say have this in viewWillAppear and viewDidLoad both, BUT in viewWillAppear is MUST).
Now in second view, to show navigation bar
[[self navigationController] setNavigationBarHidden:NO animated:YES];
Hope this will solve your problem...

Setting up a UINavigation Controller on a UIViewController as rootView

I had a tabBarApplication that I have as a template which has a UINavigation template on each tab.
I want to use that sample (sort of) and convert it into a single UIViewController in a nother application. I have presented 2 pieces of code, the first one is my template and the latter is what I am trying to make. Could anyone please give me some hints or help with how to that right? I keep getting errors, but they do not make sense to me as the tabBarApp does not need it a viewController declared.
First Code (the example):
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[self setupFetchedResultsController];
if (![[self.fetchedResultsController fetchedObjects] count] > 0 ) {
NSLog(#"!!!!! ~~> There's nothing in the database so defaults will be inserted");
[self importCoreDataDefaultRoles];
}
else {
NSLog(#"There's stuff in the database so skipping the import of default data");
}
// The Tab Bar
UITabBarController *tabBarController = (UITabBarController *)self.window.rootViewController;
// The Two Navigation Controllers attached to the Tab Bar (At Tab Bar Indexes 0 and 1)
UINavigationController *personsTVCnav = [[tabBarController viewControllers] objectAtIndex:0];
UINavigationController *rolesTVCnav = [[tabBarController viewControllers] objectAtIndex:1];
return YES;
}
Second Code (what I am trying to make):
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[self setupFetchedResultsController];
if (![[self.fetchedResultsController fetchedObjects] count] > 0 ) {
NSLog(#"!!!!! ~~> There's nothing in the database so defaults will be inserted");
[self importCoreDataDefaultRoles];
}
else {
UIViewController *mainViewController = (UIViewController *)self.window.rootViewController;
UINavigationController *readingsTVCnav = [[mainViewController viewController] objectAtIndex:0];
// Override point for customization after application launch.
return YES;
}
The fetching parts of the code are related to Core Data which already set up and working.
The reason for this change is that I want to have a plain view controller set up as the initial screen rather than the tabBarConfiguration.
Cheers Jeff
EDIT: I have added an image for clarity
From what you describe and depict in your image, you have the navigation controller set up as your app's root view controller. So you can access it (if you need to) in your app delegate's didFinishLaunchingWithOptions: method as follows:
UINavigationController *navController = (UINavigationController *)self.window.rootViewController;
Although for your app I don't think there's any reason you need to reference the nav controller from your app delegate. All the setup you need (with the exception of your code data code, which you say is already working) can be handled through the storyboard.
In your nagivationController's root viewController (the one with all the buttons) you should set up a segue from each button to the approperiate viewController in your storyboard. Bure sure to set then up as "push" segues so that it will push the view controller onto your navigationController's navigation stack. If there is any particular setup you need to do for the child view controller when the segue happens, you can implement the prepareForSegue: method like this:
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([segue.identifier isEqualToString:#"ShowMyViewController"]) {
MyViewController *vc = (MyViewController*)segue.destinationViewController;
vc.title = #"My Title";
vc.someProperty = #"Some Value";
}
}
You can (and should) identify each of your segues in the storyboard with a unique identifier so that you can identify them when this method is called.

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