I am trying to use different Navigation Bar Button Items for a single View Controller.
The View Controller can be :
pushed inside a Navigation Controller
presented modally inside a navigation controller
If it's presented modally, I need a close left bar button to dismiss the modal.
Is there a way to know if the VC is presented modally in order to set a dismiss left bar button accordingly?
I solved this problem by implementing such a method on UIViewController category
and then using this method in viewDidLoad to determine, whether the current controller presented modally or by pushing into navigation controller:
- (BOOL)isModal {
if (self.viewController.navigationController && self.viewController.navigationController.viewControllers.firstObject == self.viewController) {
return YES;
}
return NO;
}
Related
Tab bar have three view controllers. and I want to start third view controller of navigation controller when opening the tab bar. When tapping back button on third view controller, move to second view controller.
How to start third view controllers and push first, second view controllers.
It has each segue.
just access your navigation controler and call setViewControllers
let nvc = (tabBarController?.viewControllers?[0] as? UINavigationController)
nvc?.setViewControllers([UIViewController1, UIViewController2, UIViewController3], animated: false)
I have the following in Interface Builder:
The top left is my main view controller where I have 2 buttons that have segue to two UIViewControllers. These two UIViewControllers are linked with the Tab Bar Controller. However, how could I make those 2 buttons to link to specifically to one/other views? Right now it's connected specifically, but it (or something else) causes the bar tab not show up.
Is it the problem that I don't have the Tab Bar Controller connected to the main view?
Yes, you're right that the problem occurs because the tab bar controller needs to be the destination of the segues. Fix it like this:
In IB, erase the segues from the two buttons and create two new ones, one from each button to the tab bar controller. Give each one an identifier, like buttonA from one button and buttonB from the other.
In the view controller, implement prepareForSegue for each segue understanding that the destination is a tab bar controller and that each segue requires a different tab selection...
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:#"buttonA"]) {
UITabBarController *tabBarController = (UITabBarController *)segue.destinationViewController;
tabBarController.selectedIndex = 0;
}
if ([segue.identifier isEqualToString:#"buttonB"]) {
UITabBarController *tabBarController = (UITabBarController *)segue.destinationViewController;
tabBarController.selectedIndex = 1;
}
}
That's not quite how the tabBarController works.
I can see your initial view controller is the one on the top left, and it pushes either of the other two on the right on to the navigation stack if you push a button. But in your current setup, at no point does the tab controller itself get pushed on to the stack.
Instead, you would want to have your initial view controller push the tab bar controller on to the stack, through a button or otherwise, and the tab bar controller will display your other two view controllers as its setup to do.
I have a view controller that has a navigation bar. It is the root view controller of the navigation controller. I have another view controller that can be segued from a button on the first controller. Up to this point, everything works fine; there are navigation bars on both view controllers.
However, from the second view controller, I want to be able to segue back to the first controller. When doing this, it removes the navigation bar from both of the view controllers.
How can I get the navigation bar on both view controllers with buttons as transitions? Thanks!
Implement below method in your both viewcontroller,
- (void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self.navigationController setNavigationBarHidden:NO animated:NO];
}
You may hiding navigationbar somewhere.
Try this in storyboard:
Select the navigation controller -> Attributes Inspector -> Under Navigation controller and Bar Visibility leave the "Show navigation bar" blank
I have a tab view controller with a navigation controller. In the first tab item I click on a button in a view that pops up a view with animated: YES.
Then when that view is done I hit another button that dismisses it. Like:
[self dismissViewControllerAnimated:NO completion:^{
ProfilesViewController *profile = [[ProfilesViewController alloc] init];
[self.navigationController pushViewController:profile animated:YES];
//SHOW YOUR NEW VIEW CONTROLLER HERE!
}];
But everytime this code runs, it dismisses the view, DOES NOT push the profiles controller, and shows the view from the first tab bar item.
How do I push the ProfilesViewController to the screen with a Back arrow?
If you are using dismissViewControllerAnimated to dismiss that means that the VC is presented modally. As such, it doesn't have a navigation controller (so self.navigationController is nil) and thus it can't push anything into the navigation controller.
You should really add a property to the controller which is a delegate or a completion block which can be used to push the controller from another controller (the one that presents it) to dismiss and push the controller.
A second option is to pass the navigation controller, it's a similar amount of code to using a block but not so good.
A crappy option is to use the parentViewController to find the appropriate navigation controller, but that sucks for many reasons.
I have a base nav controller which has a tab bar controller nested inside. inside that tab bar controller is another nav controller nested in it. If I'm in the child nav controller I can pop to root view in one of the views but it only takes me to the root view of the CHILD nav controller. Is there a way to pop back to the first nav controller?
If you are using storyboard then you can use Unwind segue approach which always works for me
Just Control + drag from "Pop to Main Screen" UIButton to Exit (green button at bottom of scene) select unwind method declared in first screen with title "Main" e.g.
-(IBAction)customUnwind:(UIStoryboardSegue *)sender
{
NSLog(#"Unwind successful");
}
Try this,
You can pop to root view from the child nav controller by
UITabBarController *tc = (UITabBarController *)self.navigationController.parentViewController;
[tc.navigationController popToRootViewControllerAnimated:YES];