Back button of Navigation Controller does not work! - iphone

For some reason, if I try to go back to the main menu using the back button on the upper left corner, only the title returns to the previous menu, but not the view controller. View controller would return to the previous menu only if I explicitly call popViewControllerAnimated using some other button.
Is there anyway to solve this? I think I've coded something wrong. Tried googling but couldn't find any cases like mine.

I'm getting the exact same problem. Here is my code:
- (IBAction) showGameView:(id) sender {
gameView = [[TCGameViewController alloc] initWithNibName:#"TCGameViewController" bundle:[NSBundle mainBundle]];
[self.navigationController pushViewController:gameView animated:YES];
[gameView release];
}
And when I am done with gameView, I do this:
[self.navigationController setNavigationBarHidden:NO animated:YES];
But all it does when I push the 'back' button is cycle through the navigation bar, but never pops the view. I don't even know how to debug it.
In my other view, "infoView" I call the same code as before except the NavBar is never hidden, but it works just fine.
helps!

This problem can occur when you override the following method in your custom view controller:
- (UINavigationItem*)navigationItem
But you don't specify a UIBarButtonItem for the leftBarButtonItem property of the returned UINavigationItem.
If you use a custom navigationItem, and want the standard back button functionality, you could add a method as follows (remember that every UIViewController has a reference to the navigationController that containts it):
- (void)backButtonTapped
{
[self.navigationController popViewControllerAnimated:YES];
}
And then setup part of the custom navigationItem as follows:
- (UINavigationItem*)navigationItem
{
UIBarButtonItem* newLeftBarButton = [[UIBarButtonItem alloc] initWithTitle:#"Back"
style:UIBarButtonItemStyleBordered
target:self
action:#selector(backButtonTapped)];
UINavigationItem* navigationItem = [[[UINavigationItem alloc] init] autorelease];
Hope this helps.

Related

"Back" button doesn't show up in UINavigationController

I'm using the following code to try to make a "back" button for my app, the view that this code is located is in a modal view (if that has any bearing?):
navBar = [[UINavigationController alloc] initWithRootViewController:tvController];
[navBar.view setFrame:CGRectMake(0, 0, 320, 460)];
self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle: #"Back"
style: self.navigationController.navigationItem.leftBarButtonItem.style
target: self
action: #selector(backAction)];
navBar.navigationItem.backBarButtonItem.enabled = YES;
[self.view addSubview:navBar.view];
The view does not show at all, thank you for any tips!
EDIT: Even if I use a leftBarButtonItem, it still does not show up, I think there is some problem with the self.navigationItem bit of my code?
You need to make sure that when you present the modal view that you wrap it in a UINavigationController, then you'll have a valid navigation bar to manipulate. Otherwise you'll change the navigationItem all you want but it won't show up because you're not in a navigationController.
So when you go to present the view controller you're probably doing something like this.
SomeViewController *someViewController = [[[SomeViewController alloc] init] autorelease];
[self presentModalViewController:someViewController animated:YES];
What you want to do is present it like this
SomeViewController *someViewController = [[[SomeViewController alloc] init] autorelease];
UINavigationController *navigationController = [[[UINavigationController alloc] initWithRootViewController:someViewController] autorelease]
[self presentModalViewController:navigationController animated:YES];
Then when you're in the modal view you'll have a valid navigation bar that you can manipulate. Altering the leftBarButtonItem at that point will actually do something and be visible.
If you're trying to make this show a back button though you're probably "doing it wrong" typically if you're presenting something modally like this you'd show a "done" button. However by wrapping this with a navigation controller like this it does allow the modal view to then push and pop view controllers and operate as a normal navigation stack. But the root of it should probably have a "done" button not a back to return back to its previous state.
The backBarButtonItem property needs to be defined on the previous item in your stack, i.e. on the view controller you are going back to, not the current one.
EDIT:
OK, I see now you are adding your own custom navigation bar. In that case, you cannot use the view controller's navigation item. You must instead push your own navigation items on to the navigation bar and access those instead. For example:
UINavigationItem *item = [[UINavigationItem alloc] initWithTitle:#"Back"];
item.leftBarButtonItem = ...;
[navBar pushNavigationItem:item animated:NO];

UINavigationItem BackBarButtonItem not replaced

I'm having a curious issue with backBarButtonItem. I want to replace its title in the entire application for "Back" and replacing the back button works in most of -viewDidLoad event but in other views it's not working and show the name of the previous view. Has someone has the same problem?
P.S. The way to replace the backBarButtonItem is the standard one instantiating an UIBarButtonItem and setting it to viewController.navigationIten.backBarButtonItem property.
The backBarButtonItem does not set the back button that is shown in the current view, it sets the back button that navigates to the current view, i.e. the back button in the next view.
This makes sense because the back button's title is usually the title of the previous view controller.
If you want to set the left button in the navigation bar directly, use self.navigationItem.leftBarButtonItem.
when you push the view from your current view at that time after allocate your next viewcontroller object ,just put bellow line
YourViewController *objView = [[YourViewController alloc] initWithNibName:#"YourViewController" bundle:nil];
self.navigationItem.title=#"Back";
[self.navigationController pushViewController:objView animated:YES];
your Next View will Appear with Back Button....
:)
Well, at last I've found the solution to this issue.
If you want that any backBarButtonItem of your application has the same title a good approach is to subclass UINavigationController and override - (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated to replace the back button.
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
UIBarButtonItem *_backButton = [[UIBarButtonItem alloc] initWithTitle:NSLocalizedString(#"BackButtonLabel", "")
style:UIBarButtonItemStyleDone
target:nil
action:nil];
viewController.navigationItem.backBarButtonItem = _backButton;
_backButton = nil;
[_backButton release];
[super pushViewController:viewController animated:animated];
}
By this way every back button in your application will have the same title.
I hope this will be helpful for anyone else.

iPhone: Navigate to another view with transition style and Back button set

I have following code which add BackButton on my view's navigation item's tabbar. It works fine.
// Add back button
UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:#"Back" style:UIBarButtonItemStylePlain target:nil action:nil];
[view.navigationController setNavigationBarHidden:NO animated:YES];
view.navigationItem.backBarButtonItem = backButton;
view.navigationController.navigationBar.barStyle = UIBarStyleBlack;
[backButton release];
I use following line to navigate to my new view controller but it gets presented with default animation.
[view.navigationController pushViewController:viewController2 animated:YES];
I want to change the way it gets presented so I tried to do it following way.
[viewController2 setModalTransitionStyle:UIModalTransitionStyleFlipHorizontal];
[view.navigationController presentModalViewController:viewController2 animated:YES];
This works fine but I lost my BackButton..!! Is there anyway to present my new view controller with specific transition style and also keep my back button as is?
Thanks.
I found the answer to your question. Put a navigation bar on your viewController2 and add a bar button to it using either interface builder or using code. Then in the action of button press
In your viewController2.m write this function and link it up with the button press if you have added the bar button through interface builder.
-(void) backButtonPressed : (id) sender
{
[self dismissModalViewControllerAnimated:YES];
}
This should solve your problem.
Doing a pushViewController will carry forward the navigationBar and all for you but in your case presenting a viewController as modalViewController will not give you the navigationBar by default so you have to add it manually in your modalViewController which is viewController2 in your case.
Please let me know if you are still facing problems. We can fix it soon and save you some time and frustration.
Cheers!!!

Back button on UINavigationController

I know that it could seem strange but i need to add a back button on the navigation Bar of the first navigationController's view. I tried like this:
UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:#"Foo" style:UIBarButtonItemStyleBordered target:self action:#selector(foo:)];
self.navigationItem.backBarButtonItem=backButton;
if instead of backBarButtonItem i write leftBarButtonItem the button is showed. My problem is that i need an arrow button as the normal back button. Is this possible?
Usually this works out of the box, but sometimes with modal views / action sheets you may need this. Just before you instantiate your viewcontroller and push it onto navigationcontroller stack, try
UIBarButtonItem *newBackButton = [[UIBarButtonItem alloc] initWithTitle: #"Back" style: UIBarButtonItemStyleBordered target: nil action: nil];
[[self navigationItem] setBackBarButtonItem: newBackButton];
[newBackButton release];
DetailViewController *detailVC = [[DetailViewController alloc]init];
[self.navigationController pushViewController:detailVC animated:YES];
[detailVC release];
I don't think you can do that on the first NavigationController view, because you need to set the backBarButtonItem property in the parent controller, before the child controller is pushed. Also, according the to the Apple docs, the target & action of the backBarButtonItem must be nil.
This question about creating a left-arrow button on a UIToolbar may give you some ideas of how you could work around this using a custom image (for the leftBarButtonItem).
or you could also do the following - I prefer this method. I got this from a different post.
Use following psd that I derived from http://www.teehanlax.com/blog/?p=447
http://www.chrisandtennille.com/pictures/backbutton.psd
Then I just create a custom UIView that I use in the customView property of the toolbar item.
Works well for me.
Hope that helps a little
Of course you can do this. You just need to change the leftBarButtonItem's title to back
then you will get a nice left arrow button with the title back. Then you just change the selector to actually perform a method when the button is clicked. So #selector(foo:)
Here some code on how to achieve the above:
self.navigationItem.leftBarButtonItem.style = UIBarButtonItemStyleDone;
self.navigationItem.leftBarButtonItem.title = #"Back";
self.navigationItem.leftBarButtonItem.target = self;
self.navigationItem.leftBarButtonItem.action = #selector(endTextEnteringButtonAction:);
Let me know if that helps.
Apple Document says:
When this navigation item is immediately below the top item in the stack, the navigation controller derives the back button for the navigation bar from this navigation item.
So If your navigation item is the top of the Stack (as we are talking here) you can't add the back button to the navigation controller, simply because no place he can navigate back to it because it's the top item in the stack.
Updated Answer :
After I searched I found work a round to make a back button in your root view controller in Navigation controller in these link
It's very simple :)
[self.navigationItem setHidesBackButton:YES animated:YES];
UIBarButtonItem* backButton = [[UIBarButtonItem alloc] initWithTitle:#"Start" style:UIBarButtonItemStyleBordered target:self action:#selector(initializeStuff)];
self.navigationItem.leftBarButtonItem = backButton;

Unwanted Edit button in my navigation bar?

I've got the following code in my app to display a modal view:
InfoTableViewController *infoTableViewController = [[[InfoTableViewController alloc] initWithNibName:nil bundle:nil] autorelease];
infoTableViewController.title = #"Pirateometer";
infoTableViewController.navigationItem.rightBarButtonItem =
[[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone
target:self action:#selector(dismissInfo)] autorelease];
navController = [[UINavigationController alloc] initWithRootViewController:infoTableViewController];
[self presentModalViewController:navController animated:YES];
[navController retain];
However when I run, instead of the Done button on the right of my navigation bar I have an Edit button. If I change .rightBarButton to .leftBarButton my Done button appears on the left as expected, but the Edit button is again there on the right.
Am I supposed to specially remove this unwanted Edit button in code, or am I doing something wrong that is making it appear in the first place? If I have to remove it, how do I go about doing so?
Make sure in your -viewDidLoad method of InfoTableViewController that you're not setting the right button to the edit button.
In the default UITableViewController subclass stub code, there is a commented out line which does this. Perhaps you've accidentally uncommented it?
Setting it in -viewDidLoad will execute after you've already set it in your included code here, as the method doesn't run until the viewController is actually loaded (ie when you present it modally).