UITabBar disappears after pushed to new view controller - ios

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;
}

Related

Build Hierarchy in Tabbarcontroller with Navigationcontroller

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:

How to set custom segue actions through navigation controllers for viewControllers

I would like to have my application have custom buttons in the CameraViewController; one pushes to Rustles ViewController (Top VC in photo below) and the other transitions to ViewController (Bottom VC).
Right now my application can properly segue to the viewControllers by using the following method:
-(void)segueToRustlesTableViewController{
if (debug==1) {NSLog(#"Running %# '%#'", self.class, NSStringFromSelector(_cmd));} // simple debug statement, can ignore
// Instantiate nav controller which segues to table view
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPhone" bundle:nil]; // must assume only IPhone
RustlesTableViewController *rustlesTVC = (RustlesTableViewController *)[storyboard instantiateViewControllerWithIdentifier:#"RustlesView"];
[self performSegueWithIdentifier:#"tableSegue" sender:self];
[self.PickerController presentViewController:rustlesTVC animated:NO completion:nil];
}
However when I get to the UIViewControllers I can't transition back to the old UIViewControllers, presumably because I have no Navigation Controllers embedded in each UIViewControllers.
My code right now wouldn't work for a NavigationController but I don't really know how to transition to the NavigationController and then the UIViewControllers after the Navigation Controller.
How do I transition from CameraViewController to aNavigationController and then to the RustlesViewController?
If you aren't making use of a navigation controller, I would make a custom button in the spawned view controller (Rustles, View) and call
[self.presentingViewController dismissViewControllerAnimated:YES completion:nil];
I believe this should work.

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];

How do I instantiate a storyboard with a given root viewcontroller and initial viewcontroller?

I have a storyboard in my application with a navigation controller and several views. This automatically puts a navigation bar with a back button into any views that are not the root view.
However, sometimes I navigate away from this storyboard to an individual nib. I want to navigate back to the storyboard, but not necessarily to the original root view. I currently use this method to do so:
+(void) TransitionOnStoryboard:(NSString*)storyboard to:(NSString*)identifier withViewController:(UIViewController*)viewController
{
UIStoryboard *sb = [UIStoryboard storyboardWithName:storyboard bundle:nil];
UIViewController *vc = [sb instantiateViewControllerWithIdentifier:identifier];
vc.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[viewController presentViewController:vc animated:YES completion:NULL];
}
This shows the view I want but without the navigation bar. How do I specify my navigation controller or root view, such that the app knows to put a navigation bar with a back button in?
Thanks
The answer is to leave your navigation controller underneath the view controller you add from a nib.
Present the nib as a full0-screen modal. That gets rid if your navigation bar, as desired. From that new view controller, you can push more modals, add a navigation controller, or whatever.
Note that you could do all of this and stay inside your storyboard as well.
Once you are done, dismiss the modal to reveal your navigation controller, and you are back in business with your storyboard. You can push a new view controller onto your navigation controller without animation and it should appear as the front-most VC when you pop the modal that came from a nib.
I'm sure that this isn't the ideal way to solve this problem, but it did work very nicely for me.
Essentially, I removed all the views from the view controller that had been generated since I navigated away from the storyboard, but before the current view and popped the current view. In this case, these views were of one class (CheckboxListViewController) and so could be removed quite simply as below:
+(void) navigateToMainMenu:(UINavigationController*)navigationController
{
[QuickView removeFromNavigationController:navigationController allOfViewControllerWithClass:[CheckboxListViewController class]];
[navigationController popViewControllerAnimated:YES];
}
+(void) removeFromNavigationController:(UINavigationController *)navigationController allOfViewControllerWithClass:(Class)viewControllerClass
{
NSMutableArray *keptViewControllers = [[NSMutableArray alloc]init];
for (UIViewController *viewController in navigationController.viewControllers)
if (![viewController isKindOfClass:viewControllerClass])
[keptViewControllers addObject:viewController];
navigationController.viewControllers = keptViewControllers;
}
(note- QuickView is the name of the class that contains these methods.).
Any other classes that you do not want your pop to navigate back to can be removed by calling:
[QuickView removeFromNavigationController:navigationController allOfViewControllerWithClass:[YourClassName class]];
In the navigateToMenu method.

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