Can't rename or set new backBarButtonItem in UINavigationBar - objective-c

I am using the XCode 4.3.2 and only want to set the text of my back button in my UINavigationBar.
Theh simple way is use
- (void)loadView {
[super loadView];
self.navigationItem.backBarButtonItem =
[[UIBarButtonItem alloc] initWithTitle:#"Back"
style: UIBarButtonItemStyleBordered
target:nil
action:nil];
}
But id don't work. I open my Storyboard and see this:
The back button is disable. So, I can't set the button or disable it. What can I do now?

The backBarButton is used to set what the back button will say on your next view controller that you push, i.e. what the back button will say to let the user know how to get back to the current view controller. It's not used to control what the back button says on the current view controller. That's a common source of confusion.
In terms of what appears in IB, I'm not at all sure about what you're doing there. If you have a navigation bar, and you're pushing view controllers as the user goes through the app, there's nothing you need to do in IB (other than making sure you've got your navigation controller set up in your initial view). But there's no need to set up the back button in IB.
If you're trying to do something else, let us know, but that's the standard flow.

Related

Adding an info button to a navigation bar

Currently my project consists of 5 tab bar controllers, each their own navigation controller, the setup is mainly done within the app delegate and all of this is done through code, not nib files. I have a class for every tabbar/nav controllers.
My goal in this problem is to code a UIBarButtonItem on the navbar within one of my tabbarcontrollers.
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:#"Info" style:UIBarButtonItemStyleBordered target:self action:#selector(pushToInfoController)];
I basically use that piece of code to display the button within my HomeView (tab bar 1).
Now, when the user presses the button, I want to push to a new view controller where I can display info on the use of the app and other instructions on how to use it, this isnt really important, what is, is getting the button to do what it needs to do.
I plan on creating a function -(void) pushToInfoController to be the selector function but i really dont know how to go about this.

Add some Operations to the back button of a NavigationViewController

I want to force the back button of my navigationViewController to call the dissmissmodalViewController to prevent the fact that the user tap the back button to fast and the app send a message to a deallocated instance... how can I solve?
Thanks
You question feels a bit odd because the back button typically does something like:
[self.navigationController popViewControllerAnimated:YES];
I'm not sure how that is impacting any modal view controllers. If you really need to change its functionality, then you would basically hide the built in back button and replace it with your own custom one kind of like this: (put this in viewDidLoad)
[self.navigationItem setHidesBackButton:YES]; //hide the built in button
//create your new button
UIBarButtonItem *b = [[UIBarButtonItem alloc]initWithTitle:#"new-back-button" style:UIBarButtonItemStyleDone target:self action:#selector(customBackButton:)];
//set the new button
self.navigationItem.leftBarButtonItem = b;
then setup your new method to handle the button push
- (IBAction)customBackButton:(id)sender {
[self.navigationController popViewControllerAnimated:YES];
}
good luck with your project.

Adding BarButtonItems to backButton in view controller

i have a view controller, which is standalone and has two left UIBarButtonItem, however when i push it, i want to have these two buttons + the back button
i tried
- (void)viewDidLoad
{
[super viewDidLoad];
// back
if (self.navigationController.navigationItem.backBarButtonItem) {
self.navigationItem.leftBarButtonItems = [NSArray arrayWithObjects:self.navigationController.navigationItem.backBarButtonItem, self.barButtonFilter, self.barButtonFilterContacts, nil];
} else {
self.navigationItem.leftBarButtonItems = [NSArray arrayWithObjects:self.barButtonFilter, self.barButtonFilterContacts, nil];
}
}
if there is a back button, than add, else replace
but i didnt work
I am not able to get your problem but according to your caption you want to replace you back button of UINavigationController with a bar button item, in that case you simply need to have a custom button in place of back Button:
UIBarButtonItem *backButton= [[UIBarButtonItem alloc] initWithTitle:#"yourTitle" style:UIBarButtonItemStylePlain target:self action:#selector(someFunction:)];
self.navigationItem.rightBarButtonItem = backButton;
[backButtonrelease];
If this is not your problem please elaborate.
So the issue here is that a UINavigationBar can only have one leftButtonItem and one rightButtonItem. But What you can do is in the center of the UINavigationBar you can have a UIView. You can use this to place the buttons on.
Someone has the code here: adding-buttons-to-the-titleview-of-navigationbar-without-having-to-repeat-code
From Apple's iOS Human Interface Guidelines:
Use a toolbar instead of a navigation bar if you need to offer a
larger set of controls, or you do not need to enable navigation.
Avoid crowding a navigation bar with additional controls, even if
there appears to be enough space. The navigation bar should contain no
more than a view’s current title, the back button, and one control
that manages the view’s contents. If, instead, you use a segmented
control in the navigation bar, the bar should not display a title and
it should not contain any controls other than the segmented control.
http://developer.apple.com/library/ios/#documentation/userexperience/conceptual/mobilehig/UIElementGuidelines/UIElementGuidelines.html

Is there a way to select a segue anchor programmatically?

Suppose I have a Storyboard containing a view that contains a button. When the user presses this button, a popover comes up.
Thus, I need to set an anchor by dragging the segue to the button using Xcode (and then do performSegueWithIdentifier:).
So, my question is: is there a way to set this "anchor" programmatically?
Thank you.
In my case I've added programmatically several UIBarButtonItem.
The problem of only using an invisible view as an archor is that, if like in my case, the size of the UIBarButtonItem is changing it's size, the arrow of the popover doesnt appear centered, and althought it works, looks a bit strange.
How to solve it.
Create a small view in storyboard ( the size doesnt really matter ), make it invisible, and link it.
In my case this is called invisibleViewAsArchor
Connect the UIBarbutton item with the follow action.
-(IBAction) showMyPopover:(id)sender {
if([self.popoverController isPopoverVisible])
{
[self.popoverController dismissPopoverAnimated:YES];
}else{
self.invisibleViewAsArchor.frame = CGRectMake([sender view].frame.origin.x,
[sender view].frame.origin.y-50,
[sender view].frame.size.width,
[sender view].frame.size.height);
[self performSegueWithIdentifier:#"segue_to_something" sender:self];
}
}
as you can see before it shows the popover (with performSegueWithIdentifier), I'm changing the frame
of the Archor with the values from the button that has fired the event.
Hope it helps.
In the storyboard anchor the popover to some arbitrary button. Don't worry too much about which one as it will get overridden in the code.
In the view controller method prepareForSegue, add the code:
let dest = segue.destinationViewController
dest.popoverPresentationController?.barButtonItem = <your bar button here>
or if you want to anchor to a view instead
dest.popoverPresentationController?.barButtonItem = nil
dest.popoverPresentationController?.sourceView = <your view here>
You can't programmatically create segue's as explained here: Creating a segue programmatically, however, you can configure which destination controller you want to display at run-time. This is explained in the apple documentation here: Configuring the Destination Controller When a Segue is Triggered.
Hopefully this helps!
I had the same problem where I was creating a BarButtonItem programmatically. You may also be able to get around it by creating an invisible, disabled button which you can set as the anchor in IB.

How do I add a navigation bar's Done button to a popover's passthroughViews?

I'm working in an iPad app that has a split view with a navigation controller in the detail view. The deepest view that can be in the navigation stack is an edit view where the user can edit data. I put an edit button as the rightBarButtonItem and when editing starts, change it to a done button.
When editing commences and the user touches on a particular field, I present a popoverview with a list of possible choices filtered by what they are typing - a form of autofill based on all the values of that field in all other objects.
This works fine, except if you try touching on the done button. The popover eats this touch and dismisses itself. So the user has to touch done again.
I tried using the uipopovercontroller's passthroughViews property, but UIBarButtonItem is not a view and there is no documented way to get the view for the done button or even the navigation bar. I can access the variable in gdb, but it isn't accessible via KVC.
Any ideas on how I can prevent the need to tap done twice?
I've thought about a gesture recognizer on the window, but that seems messy and I'd have to handle rotation.
In case anyone gets here from google, copypaste from other question:
The only solution I found for now is to create UIBarButtonItem with custom UIButton using
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
//code for styling button
UIBarButtonItem *b = [[[UIBarButtonItem alloc]
initWithCustomView:button]
autorelease]
and then
popoverController.passthroughViews = [NSArray arrayWithObject:b.customView];
But be prepared - you cannot create UIButton that looks like UIBarButtoItem. I ended up with creating image that reassembled UIBarButtonItem.