Hiding the Cancel Button in ABPersonViewController

Overview

In this article, we’ll explore how to hide the cancel button from ABPersonViewController. This control is commonly used for selecting contacts or people in an iOS application. The provided code snippet and solution will guide you through the process of modifying the default behavior of this view controller.

Background

ABPersonViewController is a part of the Address Book framework, which allows developers to interact with contact information on an iPhone or iPad device. When using this view controller, it displays a table-based interface where users can select, edit, and delete contacts. By default, ABPersonViewController includes a “Cancel” button in its right button bar position.

Understanding the Problem

The question posed at Stack Overflow aims to eliminate this default cancel behavior from appearing when interacting with the ABPersonViewController. This is particularly useful in scenarios where the user should not be allowed to cancel or discard any contacts.

Solution Overview

To hide the “Cancel” button, we need to subclass ABPersonViewController and override its viewDidLoad method. Within this overridden method, we’ll set the rightBarButtonItem property of the navigation item to nil, effectively removing it from the view controller’s interface.

Subclassing ABPersonViewController

First, let’s create a new class that inherits from ABPersonViewController. We’ll call this subclass PersonViewController.

@interface PersonViewController : ABPersonViewController

@end

This is a straightforward step; we’re creating a new class that will serve as the base for our modified view controller.

Overriding viewDidLoad

Next, we’ll override the viewDidLoad method to achieve the desired behavior. This method is called when the view controller’s view is loaded into memory, providing an ideal opportunity to perform any necessary setup or customization.

@implementation PersonViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.navigationItem.rightBarButtonItem = nil;
}

@end

By calling [super viewDidLoad], we ensure that the default implementation of viewDidLoad from ABPersonViewController is executed first. Then, we set the rightBarButtonItem property to nil, effectively removing it from the view controller’s interface.

Verifying the Solution

To verify our solution, let’s create a new project in Xcode and add this code snippet:

Create a new iOS Single View App project.
Open the main.storyboard file and drag a “View Controller” object onto the canvas.
Select the newly created view controller and open its Identity Inspector (right-hand sidebar).
Set the Class to PersonViewController.
Run the app on a simulator or device.

Observe that, when you navigate to the contact selection screen, the cancel button should be absent. This indicates that our solution has successfully removed the default cancel behavior from ABPersonViewController.

Additional Considerations

While this approach is effective for removing the “Cancel” button, it may also inadvertently remove any other right-aligned buttons that were added programmatically.

If you need to preserve specific buttons while removing the default cancel button, consider creating a custom view controller subclass instead of modifying an existing one. This will give you more flexibility in designing your application’s UI.

Conclusion

In this article, we’ve explored how to hide the “Cancel” button from ABPersonViewController using subclassing and overriding its viewDidLoad method. By doing so, we can provide a custom interface that allows users to select and edit contacts without the possibility of canceling their actions.

By understanding the underlying mechanics of ABPersonViewController and how to modify its behavior through subclassing and overriding, you can create more tailored user interfaces for your iOS applications.

Code References

References

[1] - “Address Book Framework” (Apple Developer Documentation). [2] - “ABPersonViewController Class Reference” (Apple Developer Documentation).

Note: The references provided in the article are subject to change and may not remain accurate over time. For the most up-to-date information, please consult the Apple Developer Documentation website.

Last modified on 2023-08-11