i created a navigation based application for my project.. i replaced the launch class from a UITableView subclass to UIViewController subclass without replacing the default tableView in it. Now when i navigate to other classes from this class no back button is displayed. i even tried the following code but got no results.. how can i enable the backbutton in my navigation bar?? in btw i just updated my iPhone to iOS 4.2.1 just want to confirm if it has some bug due to which back button is not displayed??
UIBarButtonItem *_backButton = [[UIBarButtonItem alloc] initWithTitle:#"Back" style:UIBarButtonItemStyleDone target:nil action:nil];
self.navigationItem.backBarButtonItem = _backButton;
There's a hideBackButton property on UINavigationItem. You could set that to false, perhaps?
http://developer.apple.com/library/ios/#DOCUMENTATION/UIKit/Reference/UINavigationItem_Class/Reference/UINavigationItem.html#//apple_ref/occ/instp/UINavigationItem/hidesBackButton
However, it sounds like there's some reason why it's not showing up, like you're jumping around on the navigation stack manually or something.
Related
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.
I have added uitoolbar in uinavigationcontroller using IB (by selecting the check box - "show toolbar"). I used IB since this was easy to add flexible spacing bar buttons (I did not want to deal with spacing code programmatically).
My issue is that I want to invoke the built-in edit and add functionality for the 2 toolbar buttons I added. I know that in the navigation bar I can use the following code and it will invoke this functionality
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:nil];
Above code takes care of the "Edit view", where the table view items are shown with a delete button next to them.
How can I achieve the same for the buttons that I added to the toolbar? I am using Xcode 4. Please point me to some code examples.
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:#selector(callEdit)];
In callEdit method.
-(void)callEdit {
[self.tableView setEditing:YES];
}
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];
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.