I'm trying to change the text of the back button from within Interface Builder, but when I select the Navigation Bar and go into the Attributes Inspector and set the Back Button text to "Close" it still shows up with the title of the previous view.
How do I get this to work?
The back button will always show the previous UIViewController title or backBarButtonItem defined.
So if you have "view1" and move to "view2" you need to set the backButton in "view1" so it's displayed correctly while "view2" is presented.
(In other word "view1" is responsible to provide what should be displayed in a back button that point to it)
In this way if "view1" is follow by any views all those will have the correct back button.
Try this in -(void)viewDidload, as this method is fired after the nib has loaded:
UIBarButtonItem *backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Close" style:UIBarButtonItemStylePlain target:nil action:nil];
self.navigationItem.backBarButtonItem = backBarButtonItem;
[backBarButtonItem release];
A quick and dirty trick is to set the "title" to what name you want in the button in the willDisappear override in the view controller. Make sure to set the "title" back to the correct name on the willAppear override view controller. One drawback with this technique is that on slower units you can see it change. On iPhone 4 and later it's hardly noticeable.
Hope this helps.
Related
Well, figuring such thing was easy, I decided to get a custom action executed by my UIBarButtonItem once it's pressed. Here's the code:
UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:#"GET BACK!!!" style:UIBarButtonItemStylePlain target:self action:#selector(test)];
self.navigationItem.backBarButtonItem = backButton;
[backButton release];
[self.navigationController pushViewController:appsViewController animated:YES];
Yet, even without adding any custom views, -test isn't called at all (although the title change is applied).
As you can see, I'm applying these changes to the item right before I push the new view controller (else the title change wouldn't even work).
I've searched a lot for an answer to this, but the only trouble people seem to be having is it not replying to an action once it has a custom view. So; what am I doing wrong?
You can't set custom actions on back buttons. (Or, rather the action of the back button item is set to a internal one that does the back-behaviour.) If you want to do something when the user comes back to your view controller, consider doing it in viewWillAppear:. You might need to keep track of whether you're appearing after pushing a child view controller or appearing the first time, etc.
The back bar button item just allows you to configure the title to appear in the back button - it isn't stated in the docs but I think that, like a custom view, a custom action is ignored. It just pops the view controller.
Any button that looks like a back button and is in the left of the navigation bar should pop the top view controller from the stack. If you want to do anything else, use the left button item of the top view, or hook into the view will appear / disappear methods or the navigation controller delegate.
How can set self.navigationItem.backBarButtonItem of my RootViewController, so that the back button is rectangular instead of having a back arrow? I want to do this because I'm using a custom backBarButtonItem with an image of a grid of four squares (like the nine-square-gird image that the Facebook iPhone app uses for its home button).
Currently, in -[RootViewController initWitNibName:bundle:], I do:
self.navigationItem.backBarButtonItem =
[[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:#"go-home.png"]
style:UIBarButtonItemStylePlain
target:nil action:NULL];
Note: This does not cause a memory leak as I'm using ARC.
But, this makes the button have a left arrow. Is there a simple fix to make the button rectangular on all sides?
I know I could set the leftBarButtonItem for all of the view controllers that can get pushed from the RootViewController, but there are like five different options, so that'd be a lot of repetition. I guess I could make a method, e.g., +[Utils homeBarButtonItem], that creates the button above and then call self.navigationItem.leftBarButtonItem = [Utils homeBarButtonItem]; in each of the five view controllers' -viewDidLoad methods, but I'm wondering if there's a simple fix I'm missing.
Sadly the only way, as you suggest, is to use a leftBarButtonItem and use a button builder utility class.
Set the action of your leftBarButtonItem to pop the view controller and you're done.
[self.navigationController popViewControllerAnimated:YES];
Here is what I did, this is a dynamic questionary application;
-Created a UINavigationBased application
-Created some new UIVIewController subclasses with their xib's and designed them.
-I opened mainwindow.xib and set the navigationcontroller to has a navigation bar and a toolbar in black.
-So now when I switch back and forth between views by pushing them with the navigation controller I can see that shared toolbar and a navigationbar in every page with a backbutton, which is cool.
some of my uiviews are tableviews and some are textboxes
What I want is I want to put a "next" button on that toolbar and be able to go through my views but not with getting the row tap. With each next click I will decide which view to push.
How can I put this "shared" button? and in which class can I define its functionality? also I want to make it sometimes invisible for instance on first page and on last page of questionary.
In every page that you want to have a next button add this in the init or viewDidLoad
UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithTitle:#"Next"
style:UIBarButtonItemStylePlain
target:self
action:#selector(pushNextView)];
self.navigationItem.rightBarButtonItem = rightButton;
[rightButton release];
Now just implement pushNextView method to push what ever view you want
-(void)pushNextView{
//push next view
}
Edit
By specifying the target of your rightButton to AppDelegate (right now it points to self) you can setup the pushNextView method in your AppDelegate and manage all your views there.
I came across a very subtle issue.
Usually things are okay, but occasionally the current UIviewController has no title. When I call another viewcontroller called via
[[fruitDB navigationController] pushViewController:fruitc animated:YES];
there is no "back" button. The area on the top left of the navigation bar is still active though and I can go back.
How can I make sure the back button is still active, even if there is no title?
you can set the backBarButtonItem of the navigation item of the view controller.
Specifically, somewhere in viewController1 before pushing viewController2, do the following...
self.navigationItem.backBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle:#"Back" style:UIBarButtonItemStylePlain target:nil action:nil] autorelease];
When you push viewController2, the back button shown will be the backBarButtonItem of viewController1.
Note: Technically, apple recommends overriding the navigationItem method in your view controller, and adding buttons there, but it's really not an issue in your case.
Just before you push the next view controller why don't you try:
self.title = #"Back";??
I have a reference to a "UIBarButtonItem", is there a way I can add a custom "Back Navigation Button" to that item when it is not part of a Navigation based view?
I can add a left button:
UIBarButtonItem *backButton = [[UIBarButtonItem alloc]
initWithTitle:#"Custom Back"
style:UIBarButtonItemStylePlain target:self
action:#selector(backAction:)];
menuItem.backBarButtonItem = backButton; //This doesn't seem to work.
menuItem.popOverNavigationItem.leftBarButtonItem = backButton; //This shows a normal button
So how could I make the leftmost button look like a back navigation button?
UPDATE: This other question answered the root of my problem that was leading me to try and do this non-standard UI setup:
iPad: Merge concept of SplitViewController and NavigationController in RootView?
I think the correct way to set the back button is to set it for the view controller that you would be going back to. For example:
RootViewController > DetailViewController
If you want the back button to say "Custom Back" whilst you're on DetailViewController, you have to actually set RootViewController's back button to "Custom Back".
Hope that makes sense.
Having just struggled with this: I think the answer is “no.” You'll need a controller hierarchy.