Build Hierarchy in Tabbarcontroller with Navigationcontroller - ios

I have a Tabbarcontroller filled with 5 Viewcontrollers and Navigationcontrollers as I did here:
[self addChildViewController:VC1];
[self addChildViewController:NavigationController;
[self addChildViewController:VC2];
[self addChildViewController:VC3];
[self addChildViewController:VC4];
Now the thing is, that pressing a button on my Tabbar gets me to every ViewController easily, where I can present Xib-Files etc.
But now I want to have a Navigationcontroller, which is shown when pressing a button on my Tabbar. This Navigationcontroller itself has several Viewcontrollers.
I tried this to present my first Viewcontroller inside my Navigationcontroller (this code is from the Navigationcontroller.m):
- (void)viewDidLoad {
[super viewDidLoad];
[self addChildViewController:VC5];
[self presentViewController:VC5];
}
This expectedly did not work and gave me: Application tried to present modally an active controller.
Is there a good way to achieve such a specific goal? I'm struggling with this problem. Thanks in advance!
edit: This is how I set it up in my storyboard. In my programmatic approach the first view controller is not shown.

Instead of adding the VC5 view controller to the NavigationController as a child (unless it's meant to be a child?) add it as the root view controller when you add the NavigationController to the tab bar.
For example in your tab bar code:
[self addChildViewController:VC1];
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:VC5];
[self addChildViewController:navigationController];
[self addChildViewController:VC2];
[self addChildViewController:VC3];
[self addChildViewController:VC4];
Apple docs on UINavigationController are here: https://developer.apple.com/library/ios/documentation/UIKit/Reference/UINavigationController_Class/#//apple_ref/occ/instm/UINavigationController/initWithRootViewController:

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

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];

Adding child view to UITabBarController not call viewWillAppear

I have tab bar based application (iOS 7.1 SDK). When user start app at first time, I want show some login screen. I decided to use view controller containment (this is called in first view controller of tab bar controller):
LoginViewController *vc = [LoginViewController new];
[self.tabBarController addChildViewController:vc];
[vc didMoveToParentViewController:self.tabBarController];
[self.tabBarController.view addSubview:vc.view];
But there are some problems. View is normally visible, but in LoginViewController viewWillAppear and viewDidAppear are never called. I try to use this piece of code in all view lifecycle methods (viewDidLoad, viewWillAppear, viewDidAppear), but with no luck. I know there are some other ways to achieve what i'm trying to do. For example add child controller to first view controller of tab bar controller and hide tab bar, which works great and viewWillAppear and viewDidAppear are normally called. But because of this I get even more curious - why adding child view controller to tab bar controller don't work as expected?
You need to present or push the viewcontroller in order for the methods to get called. Just adding the view as a subview will not work.
In your case, you can explicitly call the viewWillAppear, viewDidAppear methods.
LoginViewController *vc = [LoginViewController new];
[self.tabBarController addChildViewController:vc];
[vc didMoveToParentViewController:self.tabBarController];
[self.tabBarController.view addSubview:vc.view];
[vc viewWillAppear];
[vc viewDidAppear];
It's working!
dispatch_async(dispatch_get_main_queue(), ^{
[self.tabBarController setSelectedIndex:0];
[self.tabBarController setSelectedIndex:1];
[self.tabBarController setSelectedIndex:0];
});

UITabBar disappears after pushed to new view controller

I have an UITabBarController that has 3 buttons. The second button points to ViewController1 which is connected to another view called ViewController2. After I tap a button in ViewController2 I programmatically present ViewController1 again, that works perfect except one thing. After I "arrived" to ViewController1 the tab bar disappears.
I'm using this method to navigate back to ViewController1. (exactly I navigate to its navigation controller, but already tried with the view)
- (void)presentViewControllerAnimated:(BOOL)animated {
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"storyboard" bundle:nil];
UINavigationController *firstViewNavigationController = [storyboard instantiateViewControllerWithIdentifier:#"destination"];
[self presentViewController:firstViewNavigationController animated:animated completion:nil];
}
I call here the first method
- (void)didTapButton:(id)sender {
UIButton *button = (UIButton *)sender;
CGPoint pointInSuperview = [button.superview convertPoint:button.center toView:self.tableView];
[self presentViewControllerAnimated:YES];
}
This method hides the tab bar in the ViewController2, I already tried without it, therefore there is no problem with it.
-(BOOL)hidesBottomBarWhenPushed
{
return YES;
}
I can't figure out why this thing happens, I think it's a fair solution, that worked well for a several times when I needed to present views. I've read it can happen with segues, but I'm doing it with code without segues.
Actually your code works right. There should not be tab bar when you present FirstViewController from SecondViewController. Because when you call instantiateViewControllerWithIdentifier its basically creates a new instance of that view controller, and of course, there is no tab bar.
The right way to go back to your first view controller is to pop SecondViewController (or dismiss it, if it presented modally). So your final code should be like this
- (void)didTapButton:(id)sender {
// If this view controller (i.e. SecondViewController) was pushed, like in your case, then
[self.navigationController popViewControllerAnimated:YES];
// If this view controller was presented modally, then
// [self dismissViewControllerAnimated:YES completion:nil];
}
And of course, your view controller hierarchy in storyboard must be like this:
-- UINavigationController -> FirstViewController -> SecondViewController
|
->UITabBarController____|
-...
-...
I've tried the same and got the same result.
My solution was simple, on the push do this :
UINavigationController *firstViewNavigationController = [storyboard instantiateViewControllerWithIdentifier:#"destination"];
firstViewNavigationController.hidesBottomBarWhenPushed = true; // Insert this and set it to what you want to do
[self presentViewController:firstViewNavigationController animated:animated completion:nil];
and then remove your
-(BOOL)hidesBottomBarWhenPushed
{
return YES;
}

How to create ViewController in my situation? ios7

I got first ViewController with out navigation controller, I go from it to second ViewController via
if (!self.mapViewController)
{
self.mapViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"MapViewController"];
}
[self presentViewController:self.mapViewController animated:YES completion:nil];
I send some data with prepareForSegue to it, but I need that it also be with navigation controller.
I embed in a navigation controller in storyboard but my code still called second ViewController with out navigation.
I am not a professional with the way of the storyboard, however i believe that instead of presentViewController
you should be using the following function to present a storyboard VC based on segues.
[self performSegueWithIdentifier:#"SegueIdentifierHere" sender:nil];
Make sure that in your storyboard you have incorporated a UINavigationControllerVC as well.
Give an identifier to the navigation controller in storyboard. Instantiate and present that.
UINavigationController *navVC = [self.storyboard
instantiateViewControllerWithIdentifier:#"TheNavVCWhoseRootIsMyMapViewController"];
self.mapViewController = navVC.viewControllers[0]; // your map vc is at the root
[self presentViewController:navVC animated:YES completion:nil];
You are using presentViewController:animated:completion which will indeed display a UIViewController without the UINavigationController the previous UIViewController was embedded in.
Try using the following:
[self.navigationController pushViewController:self.mapViewController animated:YES]

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