Скачать или смотреть Programmatically Change Button Size in Swift

Learn how to effortlessly change the size of a button during runtime in your iOS app using Swift, Auto Layout, and Storyboards.
---
This video is based on the question https://stackoverflow.com/q/69050285/ asked by the user 'jayb98' ( https://stackoverflow.com/u/3813375/ ) and on the answer https://stackoverflow.com/a/69051468/ provided by the user 'Vadim Belyaev' ( https://stackoverflow.com/u/426320/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Swift: Programmatically change size of a button in runtime

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Programmatically Change Button Size in Swift: A Simple Guide

When developing iOS applications, you might encounter situations where you want to dynamically adjust the size of a button during runtime based on user interactions or app states. For example, in a camera application, you may want to change the size of a zoom control button when the zoom level changes. This guide explains how to programmatically change the size of a button in Swift, particularly when working with Auto Layout and Storyboards.

The Problem

You may find yourself in a situation where you attempt to resize a button using code like:

[[See Video to Reveal this Text or Code Snippet]]

However, this approach may not yield any results. The button may not change size because it's managed by Auto Layout, which overrides your directly-set frame values based on constraints set in your storyboard.

For example, a user in a forum mentioned they were attempting to resize their buttons in an app but were unsuccessful, despite trying various code snippets. Similarly, they struggled with resizing buttons nested in a UIStackView, which adds another layer to the problem.

Understanding Auto Layout and UIStackView

Auto Layout is a powerful tool used in iOS development to define the layout of your app's user interface. It allows you to specify constraints that determine the size and position of UI elements. When Auto Layout recalculates frames during layout passes, any manual changes to the button's frame will revert, making them ineffective.

When using a UIStackView, the situation gets even more complicated. UIStackViews take care of arranging their subviews based on their constraints and intrinsic content sizes. This means that you cannot simply set the frame of a button to a desired size; you must adjust the constraints instead.

The Solution: Adjusting Constraints

To effectively change the size of a button during runtime in your camera app, follow these steps:

1. Setup Constraints in Storyboard

Open your storyboard in Xcode.

Select the button you want to resize.

Create Width and Height constraints for the button. This defines the button's size dynamically.

2. Create IBOutlet for Constraints

In your View Controller file, create IBOutlet properties for each of the constraints. For instance:

[[See Video to Reveal this Text or Code Snippet]]

3. Change the Size Dynamically

Whenever you want to change the button size (for example, when switching zoom levels), simply adjust the constraints like this:

[[See Video to Reveal this Text or Code Snippet]]

4. Trigger Layout Updates

After changing the constraint constants, you might want to call layoutIfNeeded() on the relevant view to ensure the layout updates occur immediately:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following these steps, you can successfully adjust the size of a button programmatically in your iOS app. Using Auto Layout and properly modifying constraints allows you to maintain control over your layout, ensuring that your UI behaves as expected regardless of the user's actions.

With this method, your button size can reflect the functionalities you want to provide in your application, enhancing the user experience significantly. Repeat these steps for any other buttons or UI elements that may need dynamic resizing in your app.

Happy coding!