A UINavigationController can be added to simple IPhone window application, to create a navigation bar on top of the view as shown in the diagram in the right. The following steps show how UINavigationController can be added to a simple IPhone window application:
1. Add the UINavigationController object in the header file for the
Eg. in ApplicationDelegate.h @interface section:
2. Add the following codes to the applicationDelegate.m main class in
the didFinishedLaunchingWithOptions method.
uiNavCtrl=[[UINavigationController alloc] init];
[window addSubView: uiNavCtrl.view];
3. After adding the above codes, UINavigationController has to be release in the dealloc method in the applicationDelegate.m main class.
An UINavigationController can have multiple UIViewControllers class pushed into it. If more than one
UIViewController are pushed into the UINavigationController, the last one that is pushed will be
displayed, when the application is first launched. A Back button will be automatically created if there are
more than one UIViewController class are pushed. Steps below outline how to add new
UIViewController to UINavigationController:
4. If back button is needed in all subsequence pushed viewController (to return to parent view),
the backBarButtonItem is needed to add to the root navigationController. If the title of the backBarButtonItem is not set, the default behaviour is that the back button will be created with
the title of the parent view. **Note: For default behaviour to work, all the viewController must be set with a title.
a) In XCode, under Groups & Files,
expand current project. Higfhlight Class, right
click Add->New File... Refer to the
diagram in the left.
A new file selection menu will be poped up.
b) In the new File windows, select UIViewController sub-class.
Also select with XIB for users interface option. This option
will generate the XIB file automatically. This XIB is to be used in
the interface builder, to simplify the creation of visual control in the
UIView. If this option is not selected, the XIB file has to be created
manually later after the class file is generated. This option will
save two steps of manual work to create the XIB file.
After that click on the Next button, to proceed to next step of the
c) In the following new File window, specify the name for the
UIViewController sub-class that to be created. After that click the finish button to generate the class, header and XIB files.
* Note: As part of the programming convension the class name
typically start with uppercase character and follow with lowercase
Uppercase first character is also usually used for all the following
words in the class name.
Eg. FirstView , SecondView
6. Once the UIViewController sub-class is being generated, the view can be customized according to
the requirement in the interface builder by clicking the newly created XIB file. The UI control (eg.
UISlider, UIButton, UILabel... etc) can be added to the view in interface builder.
7. To use the newly created UIViewController in the window application, it has to be pushed to the
UINavigationController. The best way is to push through the didFinishedLaunchingWithOptions
method in the applicationDelegate.m main class. Eg: add the following code to didFinishedLaunchingWithOptions in ApplicationDelegate.m, assume that FirstView is newly
FirstView *fv = [[UIViewController alloc] init]; fv.title = @"Title"; // To add a title to the UIViewController
[uiNavCtrl pushViewController: fv animated: NO];
*Note: If the animated option is set to YES, the UIView will be shown in a animated way.
Typically, if it is push through the didFinishedLaunchingWithOptions method, the animation will not show.
8. The newly created UIViewController can also be pushed through any UI controller such as UIButton ...
etc. IBAction method can be used to push the UIViewController. Eg. The following code show how this
can be done:
a) Add IBAction in the FirstView.h
-(IBAction) getSecondView: (id) sender;
b) Add IBAction in the FirstView.m in the @interface section: