How set set title to leftBarButtonItem - objective-c

I have root ViewController and detailed ViewController. When i push to detailedViewController i get leftBarButtonItem with the title from the root one. But i want the title to be just "Back", nothing more. So how to do that?
This doesn't help
self.navigationItem.leftBarButtonItem.title = #"Back";
To create my on type barButtonItem(for example 104 with left arrow) and to set it to leftBarButtonItem is terrible decision.
Is there other way than to change the title of the rootViewController manually before pushing?

From Apple's doc:
backBarButtonItem
The bar button item to use when a back button is needed on the
navigation bar.
#property(nonatomic, retain) UIBarButtonItem *backBarButtonItem
Discussion
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. When this property is nil,
the navigation item uses the value in its title property to create an
appropriate back button. If you want to specify a custom image or
title for the back button, you can assign a custom bar button item
(with your custom title or image) to this property instead. When
configuring your bar button item, do not assign a custom view to it;
the navigation item ignores custom views in the back bar button
anyway.
So, you can create create your barButtonItem (e.g. – initWithTitle:style:target:action:) and assign it to that property.
In addition, if you want to have a custom image for UIBarButtonItem (left or right) I suggest you to create a category extension like the following:
//UIBarButtonItem+Extension.h
+ (UIBarButtonItem*)barItemWithImage:(UIImage*)image title:(NSString*)title target:(id)target action:(SEL)action;
//UIBarButtonItem+Extension.m
+ (UIBarButtonItem*)barItemWithImage:(UIImage*)image title:(NSString*)title target:(id)target action:(SEL)action
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = CGRectMake(0.0, 0.0, image.size.width, image.size.height);
button.titleLabel.textAlignment = UITextAlignmentCenter;
[button setBackgroundImage:image forState:UIControlStateNormal];
[button setTitle:title forState:UIControlStateNormal];
[button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem* barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];
return [barButtonItem autorelease];
}
and then use it as
UIBarButtonItem* backBarButtonItem = [UIBarButtonItem barItemWithImage:[UIImage imageNamed:#"YoutImageName"] title:#"YourTitle" target:self action:#selector(doSomething:)];

I finally figured out all the wrinkles in this today, and it's simpler then above.
The child's back button text is based on values set in its parent. This is obvious behaviour, when you think about it: If a view controller can be reached from two parents, the back button's text should depend on which pushed it.
If the text is always the same:
Select the parent view controller's Navigation Item in the editor.
Put the text into the Back Button value.
And like that you're done. When this view controller is pushed aside by a new view controller, that new view controller will get this text as its title.
If the text is dynamic:
Select the parent view controller's Navigation Item in the editor.
Put some text into the Back Button value.
Set the title when it should change in the parent view controller: self.navigationItem.backBarButtonItem.title = dynamicText;
And, again, you're done.
To be clear, you can set this at any time in the parent view controller. It will only be shown when another view controller is pushed.
If you don't put the text in the Back Button in the designer, the process of instantiating the view controller won't create self.navigationItem.backBarButtonItem, and you can't set the title of a nil object. I believe this is where all of the confusion around this stems from.
Of course, you can create this at runtime, but if you're already doing most of your work in the storyboard/nib it's easier to let the decoder do it for you.
If you're more curious about this, I just wrote a blog post on the subject as well. It has some more details.

UIBarButtonItem *backButtonItem = [[UIBarButtonItem alloc] init];
backButtonItem.title = NSLocalizedString(#"Back", nil);
self.navigationItem.backBarButtonItem = backButtonItem;

It works for me:
[self.navigationItem.leftBarButtonItem setTitle:#"Back"];
(back arrow image and custom text)

Related

Common UIButton or UIbarbutton to navigationbar

How can we add common UIButton or UIBarButton or any UI object so that it appears in all navigationbars in the application.
The below code will work perfectly;
UIImage* image3 = [UIImage imageNamed:#"info.png"];
CGRect frameimg = CGRectMake(0, 0, image3.size.width*4, image3.size.height);
UIButton *someButton = [[UIButton alloc] initWithFrame:frameimg];
//[someButton setBackgroundImage:image3 forState:UIControlStateNormal];
[someButton setTitle:#"Category" forState:UIControlStateNormal];
[someButton addTarget:self action:#selector(popUpPicker:)
forControlEvents:UIControlEventTouchUpInside];
[someButton setShowsTouchWhenHighlighted:YES];
UIBarButtonItem *mailbutton =[[UIBarButtonItem alloc] initWithCustomView:someButton];
self.navigationItem.rightBarButtonItem=mailbutton;
self.navigationItem.leftBarButtonItem = nil;
For these, you have to use category and then you have to call it in your every view controller to have the one code for every navigationabr button action.
There is no magic formula. One way or another, you have to add the same "UIButton or UIBarButton or any UI object" to the navigationItem of every UIViewController whose view will appear under this navigation controller's navigation bar.
You can reduce the amount of repeated code by creating this object in a single place, but the act of saying
self.navigationItem.rightBarButtonItem = thisItem
or whatever it is you want to do with the bar button item, will have to be performed separately and explicitly for every view controller.

UIButton not showing up

I am trying to create a UIButton programmatically instead of using the interface builder. I initialize and set the button frame but the button doesn't seem to appear on the view. My code is as follows:
UIButton *showInfoButton = [[UIButton alloc] init];
CGRect buttonFrame = CGRectMake(0,0, 150, 150);
showInfoButton.frame = buttonFrame;
What am I missing? Please bear with me as I am new to iOS.
You forgot to add your UIButton as a subview to the UIView you want it to display on. Since you are building UI programmatically, you need to manually add the button as a subview to the container view.
You can do so by using this line of code:
[self.view addSubview:showInfoButton];
The button might not still appear as you are making a custom button which has a transparent background colour. In order to see the button, you can set the UIButton's backgroundColor property as follows:
[showInfoButton setBackgroundColor:[UIColor blackColor]];

Set title/icon etc to TabBarItem created in IB, through code?

I have a TabBar that I've created through IB, I chose "create new project" -> "Tab bar application". Is there a way for me to access one of the TabBarItems for customization through the code?
It seems to me that something like:
[[self.tabBarController.tabBar.items objectAtIndex:0] setTitle:#"Button one"];
should set the title of that item to "Button one", but it doesen't. The title itself is not a problem (I can set that through IB aswell), however adding an Icon seems to be.
So to sum up, what I really want to know is: Is there a way to add an Icon to a TabBarItem created through IB?
SOLUTION:
Adding in viewDidLoad in the first view, being loaded automatically upon starting the app:
UITabBarController *tb = [self tabBarController];
[[tb.tabBar.items objectAtIndex:1] setTitle:#"Title"];
Let me set the title of the second button (objectAtIndex: 1). I was also able to set the image the same way, which also worked for buttons one (objectAtIndex: 0) and three (objectAtIndex: 2).
Add this to your viewDidLoad: method of one of the tabBar viewControllers and it should work:
- (void)viewDidLoad
{
[super viewDidLoad];
//Get the tabBarItem
UITabBarItem *tbi = [self tabBarItem];
//Give it a lable
[tbi setTitle:#"Title A"];
//create a image from a file for the tabBar
UIImage *i = [UIImage imageNamed:#"NiceImage.png"];
//and put it on the tabBar
[tbi setImage:i];
}
You should be able to set the image and title properties on the TabBarItems:
UITabBarItem *item = (UITabBarItem *)[tabBarController.tabBar.items objectAtIndex:0];
item.image = [UIImage imageNamed:#"home.png"];
Don't forget that the UITabBar only uses the alpha values out of the image you set, so if you don't have an alpha channel in the image you may not see anything when you set an image on the tab bar item.
I've never created a tab bar through IB (always through code), however to set title and icon I use
controller.title = #"Controller";
controller.tabBarItem.image = [UIImage imageNamed:#"image.png"];
where controller is the UIViewController added to the viewControllers' array of the UITabBarController.

How to add a simple button to the middle of a navigation bar?

i found a lot of topics around placing buttons on navigation bar but none showed me how to place a button at the center of the bar.
I found an example with a segmented control but i don't need that.
Just a button instead of the title. Is that possible? ;-)
Edit:
That will do it:
UIButton *titleButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[titleButton setFrame:CGRectMake(0, 0, 170, 35)];
self.navigationItem.titleView = titleButton;
You can set any custom view (e.g. UIButton) as a titleView property to your current navigationItem - that should do the trick.

How to create backBarButtomItem with custom view for a UINavigationController

I have a UINavigationController into which I push several views. Inside viewDidLoad for one of these views I want to set the self.navigationItem.backBarButtonItem to a custom view (based on a custom image). I don't know why, but it doesn't seem to work. Instead, I get the standard "back" button.
UIButton *backButton = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 63, 30)];
[backButton setImage:[UIImage imageNamed:#"back_OFF.png"] forState:UIControlStateNormal];
[backButton setImage:[UIImage imageNamed:#"back_ON.png"] forState:UIControlStateSelected];
UIBarButtonItem *backButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
self.navigationItem.backBarButtonItem = backButtonItem;
[backButtonItem release];
[backButton release];
I tested with a standard title and it worked. What is wrong with the above code ?
self.navigationItem.backBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle:#"Prout" style:UIBarButtonItemStyleDone target:nil action:nil] autorelease];
Thanks for any help on this.
As of iOS5 we have an excellent new way of customizing the appearance of almost any control using the UIAppearance protocol, i.e. [UIBarButtonItem appearance]. The appearance proxy allows you to create application wide changes to the look of controls. Below is an example of a custom back button created with the appearance proxy.
Use the example code below to create a back button with custom images for normal and highlighted states. Call the following method from you appDelegate's application:didFinishLaunchingWithOptions:
- (void) customizeAppearance {
UIImage *i1 = [[UIImage imageNamed:#"custom_backButton_30px"]
resizableImageWithCapInsets:UIEdgeInsetsMake(0, 15, 0, 6)];
UIImage *i2 = [[UIImage imageNamed:#"custom_backButton_24px"]
resizableImageWithCapInsets:UIEdgeInsetsMake(0, 15, 0, 6)];
[[UIBarButtonItem appearance] setBackButtonBackgroundImage:i1
forState:UIControlStateNormal
barMetrics:UIBarMetricsDefault];
[[UIBarButtonItem appearance] setBackButtonBackgroundImage:i2
forState:UIControlStateNormal
barMetrics:UIBarMetricsLandscapePhone];
[[UIBarButtonItem appearance] setBackButtonBackgroundImage:i1
forState:UIControlStateHighlighted
barMetrics:UIBarMetricsDefault];
[[UIBarButtonItem appearance] setBackButtonBackgroundImage:i2
forState:UIControlStateHighlighted
barMetrics:UIBarMetricsLandscapePhone];
}
This is just a quick example. Normally you would want to have separate images for normal and highlighted (pressed) state.
If you are interested in customizing the appearance of other controls, some good examples can be found here: http://ios.biomsoft.com/2011/10/13/user-interface-customization-in-ios-5/
I'm fairly certain that the backBarButtonItem is a read-only property. Instead of modifying the backBarButtonItem, try setting a custom leftBarButtonItem and hide the backBarButtonItem:
self.navigationItem.leftBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle:#"Prout" style:UIBarButtonItemStyleDone target:nil action:nil] autorelease];
self.navigationItem.hidesBackButton = YES;
You will also need to make sure you hook up the custom button to call the back action on the UINavigationBar.
I never been able to create a proper UIBarButtonItem with custom view and setBackBarButtonItem.
Here's the solution i found : let net UINavigationControllerDelegate handles everything! The trick here is to call the popViewControllerAnimated: method of the viewController.navigationController so you don't have to create any custom method.
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
if([navigationController.viewControllers count ] > 1) {
UIView *backButtonView = [[UIView alloc] initWithFrame:CGRectMake(0,0,70,35)];
UIButton *myBackButton = [[UIButton buttonWithType:UIButtonTypeCustom] retain];
[myBackButton setFrame:CGRectMake(0,0,70,35)];
[myBackButton setImage:[UIImage imageNamed:#"back.png"] forState:UIControlStateNormal];
[myBackButton setEnabled:YES];
[myBackButton addTarget:viewController.navigationController action:#selector(popViewControllerAnimated:) forControlEvents:UIControlEventTouchUpInside];
[backButtonView addSubview:myBackButton];
[myBackButton release];
UIBarButtonItem* backButton = [[UIBarButtonItem alloc] initWithCustomView:backButtonView];
viewController.navigationItem.leftBarButtonItem = backButton;
[backButtonView release];
[backButton release];
}
}
If your end goal is to simply replace the image used for the back button, you can use a new method on UIBarButtonItem available in iOS 5.0:
setBackButtonBackgroundImage:forState:barMetrics:
Apple Docs:
http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIBarButtonItem_Class/Reference/Reference.html
Here's a simple example that sets a custom background image for all back buttons in your app:
UIImage *toolbarBackButtonBackgroundPortrait = [[UIImage imageNamed:#"toolbarBackButtonPortrait"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 17, 0, 6)];
UIImage *toolbarBackButtonBackgroundLandscape = [[UIImage imageNamed:#"toolbarBackButtonLandscape"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 17, 0, 6)];
[[UIBarButtonItem appearance] setBackButtonBackgroundImage:toolbarBackButtonBackgroundPortrait forState:UIControlStateNormal barMetrics:UIBarMetricsDefault];
[[UIBarButtonItem appearance] setBackButtonBackgroundImage:toolbarBackButtonBackgroundLandscape forState:UIControlStateNormal barMetrics:UIBarMetricsLandscapePhone];
I would be willing to bet that this is a bug on Apple's part as I am running into the exact same problem. The reason being is that I can get a custom UIBarButtonItem to appear, but only when I don't try to use the initWithCustomView: method. Per the API, the navigation controller checks the following things when a new view controller is pushed:
If the new top-level view controller has a custom left bar button item, that item is displayed. To specify a custom left bar button item, set the leftBarButtonItem property of the view controller’s navigation item.
If the top-level view controller does not have a custom left bar button item, but the navigation item of the previous view controller has a valid item in its backBarButtonItem property, the navigation bar displays that item.
If a custom bar button item is not specified by either of the view controllers, a default back button is used and its title is set to the value of the title property of the previous view controller—that is, the view controller one level down on the stack. (If there is only one view controller on the navigation stack, no back button is displayed.)
My case (as well as yours) is 2. I specify code exactly the same as yours (i.e., creating a UIButton, setting its image properties for various states, creating a UIBarButtonItem, initializing it with the UIButton, then setting my current view controller's backBarButtonItem property to the UIBarButtonItem); however, when I later push my view controller, nothing at all is displayed on the left-hand side of my navigation controller. Strangely, I can click where the "Back" button should be, and it pops the view controller.
Interestingly, if I create a UIBarButtonItem using the initWithTitle:style:target:action: method instead of the initWithCustomView: method, it does show a custom button with a custom title. Also, as Travis mentioned, using the leftBarButtonItem property instead works just fine. I'd rather adhere to the sanctioned logic, however, by specifying the "Back" button for the current view controller -- to be displayed later when a new view controller is pushed -- instead of creating a left button for the next view controller, which, arguably, should have no concern for anything pertaining to the view controller that came before it. :-\
Set the backBarButtonItem before pushing the viewController with the navigationController. Setting the backBarButtonItem in viewDidLoad doesn't work.
Say I have MyTableViewController. When the user taps a particular row I want to push AnotherViewController using the navigationController. The code looks something like this:
// in MyTableViewController's tableView:didSelectRowAtIndexPath method...
UIBarButtonItem *backButton = [[UIBarButtonItem alloc]
initWithImage:[UIImage imageNamed:#"yourImage.png"]
style:UIBarButtonItemStyleBordered
target:nil
action:nil];
self.navigationItem.backBarButtonItem = backButton;
[backButton release];
[self.navigationController pushViewController:anotherViewController];
When anotherViewController is displayed the back button in the navigation bar will have #"yourImage.png" and the default back button style (rectangular arrow). Also note it's fine to pass nil as target. The button behaves like the back button.
Even though is already answered this worked for me:
UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:#"backArrow.png"] style:UIBarButtonItemStyleBordered target:nil action:nil];
self.navigationItem.backBarButtonItem = backButton;
[backButton release];
BTW: even in iOS4 initializing my back button with initWithCustomView: didn't work for me. ;(
I too have been having problems with customView on a navigationItem.backBarButtonItem. I suspect it's probably just b0rked in the SDK.
While the workarounds outlined here do work, I've come up with a solution which is a little more elegant: it still uses navigationItem.leftBarButtonItem, but takes care of it for you automagically (no more need for 'child' view controllers to need to know anything about their 'parent' and/or to manually set navigationItem.leftBarButtonItem).
First up, have some class be a UINavigationControllerDelegate for the UINavigationController whose back button you're interested in. Then, in this class, set up something like the following willShowViewController delegate method:
-(void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated{
// reference to view controller stack
NSArray *viewControllers = [ navigationController viewControllers ];
if( [ viewControllers count ] > 1 ){
// the view controller we'll be linking to
UIViewController *backViewController = [ viewControllers objectAtIndex: [ viewControllers count ] - 2 ];
// create custom UIBarButtonItem
UIBarButtonItem *leftButton = [[ UIBarButtonItem alloc ] initWithCustomView: someCustomView ];
// set it as the leftBarButtonItem on the incoming viewcontroller
viewController.navigationItem.leftBarButtonItem = leftButton;
// tidy up
[ leftButton release ];
}
}
I had some further problems with this; it seems that UIBarButtonItem.action and UIBarButtonItem.target don't work when it's a navigationItem.leftBarButtonItem. So, you're left with a custom back button that doesn't actually go back. I'll leave responding to touches in your custom view as an exercise for the reader (I used a UIButton), but you'll need add this method to your delegate class:
-(void)onDummyBackButtonTapped{
[ someNavigationController popViewControllerAnimated: YES ];
}
and hook it up to fire when your custom view is tapped.
backBarButtonItem is not a read-only
property. I'm not sure why it behaves
so strangely, and the above is a valid
(if less-than-ideal) workaround.
It behaves strangely because setting a vc's backBarButtonItem doesn't change anything about the appearance of the vc's navigation item - instead, it changes the button that points BACK to the vc. See updating the navigation bar from Apple FMI.
That said I haven't had a whole lot of luck getting it to work myself. If you look around this site, you'll find some threads that suggest placing code very similar to what you already have immediately before the call to push a new view on the stack. I've had some luck there, but unfortunately not when it comes to using a custom image.
The navigationController's backBarButtonItem is set on the item whose title you're trying to affect.
i.e. in Page 1's view controller, say, viewdidLoad:
self.title = #"Page 1 of 4";
self.navigationItem.backBarButtonItem =
[[[UIBarButtonItem alloc] initWithTitle:#"Page 1"
style:UIBarButtonItemStyleBordered
target:nil
action:nil] autorelease];
You would not override this in Page 2.
Documentation for UINavigationItem : backBarButtonItem makes this clear:
When this item is the back item of the
navigation bar—when it is the next
item below the top item—it may be
represented as a back button on the
navigation bar. Use this property to
specify the back button. The target
and action of the back bar button item
you set should be nil. The default
value is a bar button item displaying
the navigation item’s title.
This is how I create a custom square back button with an arrow instead of the usual text.
I simply setup a delegate for my UINavigationController. I use the app delegate for that because the window root view controller is the UINavigationController i want to control.
So AppDelegate.m (ARC):
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
((UINavigationController*)_window.rootViewController).delegate = self;
return YES;
}
#pragma mark - UINavigationControllerDelegate
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
if(navigationController.viewControllers.count > 1) {
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setImage:[UIImage imageNamed:#"back-arrow.png"] forState:UIControlStateNormal];
[button setBackgroundColor:[UIColor grayColor]];
button.frame = CGRectMake(0, 0, 44, 44);
viewController.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];
[button addEventHandler:^(id sender) {
[navigationController popViewControllerAnimated:YES];
} forControlEvents:UIControlEventTouchUpInside];
}
}
I'm using BlocksKit to catch the button tap event. It's very convenient for stuff like this but you can also use the regular addTarget:action:forControlEvents: method
I think I found the solution for this.
Simply set the button on the navigation item on the previous controller (The one that you want to go back to)
So if I have for example a root controller
and I push a second controller and want to customize the back button then I should do the following:
self.navigationItem.backBarButtonItem = [[[UIBarButtonItem alloc]
initWithImage:[UIImage imageNamed:#"ico.png"] style:UIBarButtonItemStyleBordered
target:nil action:nil] autorelease];
Where self is the root view controller and not the second one.
My Logic:
Create a custom button (aka a custom view subclass)
Initialize a barbutton item with the custom button/view
Add an action that allows us to "go back" to our previous view controller
Set the left bar button item to this custom bar button item you created
Hide the back bar button item of the view controller you're pushing to
Step 3 was important. I figured the cleanest way to simulate the "go back" was to just utilize UINavigationController's method (popViewControllerAnimated:). So, I just add that action to the navigationController of the viewController I'm pushing (viewControllerToPush) like so:
[navItemButton addTarget:viewControllerToPush.navigationController action:#selector(popViewControllerAnimated:) forControlEvents:UIControlEventTouchUpInside];
Example:
UIViewController *viewControllerToPush = [[UIViewController alloc] init];
UIImage *navImage = [UIImage imageNamed:#"your_back_button_image"];
UIButton *navItemButton = [UIButton buttonWithType:UIButtonTypeCustom];
[navItemButton setImage:navImage forState:UIControlStateNormal];
[navItemButton setImage:navImage forState:UIControlStateHighlighted];
[navItemButton setFrame:CGRectMake(0, 0, navImage.size.width, navImage.size.height)];
[navItemButton addTarget:viewControllerToPush.navigationController action:#selector(popViewControllerAnimated:) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:navItemButton];
viewControllerToPush.navigationItem.leftBarButtonItem = barButtonItem;
viewControllerToPush.navigationItem.hidesBackButton = YES;
[self.navigationController pushViewController:viewControllerToPush animated:YES];
You can use leftBarButtonItem instead of back button item. And to remove the default back button item set it to nil like follows;
navigationController?.navigationBar.backIndicatorImage = nil
navigationController?.navigationBar.backIndicatorTransitionMaskImage = nil
let button = UIButton.init(type: .custom)
button.imageView?.contentMode = UIViewContentMode.scaleAspectFit
button.setImage(UIImage.init(named: "top_back"), for: UIControlState.normal)
button.frame = CGRect.init(x: 0, y: 0, width: 75, height: 50)
button.addTarget(self, action: #selector(handleBackButton), for: .touchUpInside)
let barButton = UIBarButtonItem.init(customView: button)
self.navigationItem.leftBarButtonItem = barButton