Passed as an argument to this method is a segue object from which a reference to the destination view controller may be obtained and subsequently used to transfer data. To see this in action, begin by selecting Scene2ViewController. Finally, select the ViewController. All this method does is obtain a reference to the destination view controller and then assigns a string to the labelText property of the object so that it appears on the label.
Compile and run the application once again and note that when scene 2 is displayed the new label text appears. We have, albeit using a very simple example, transferred data from one scene to the next.
The next step is to configure the button on scene 2 to return to scene 1. It might seem as though the obvious choice is to simply implement a segue from the button on scene 2 to scene 1.
Instead of returning to the original instance of scene 1, however, this would create an entirely new instance of the ViewController class. If a user were to perform this transition repeatedly the application would continue to use more memory and would eventually be terminated by the operating system.
The application should instead make use of the Storyboard unwind feature. This involves implementing a method in the view controller of the scene to which the user is to be returned and then connecting a segue to that method from the source view controller.
This enables an unwind action to be performed across multiple levels of scene. To implement this in our example application, begin by selecting the ViewController. All that is required of this method for this example is that it set some new text on the label object of scene 1. Once the method has been added, it is important to save the ViewController.
Once again, run the application and note that the button on scene 2 now returns to scene 1 and, in the process, calls the returned method resulting in the label on scene 1 changing. In addition to wiring up controls in scenes to trigger a segue, it is also possible to initiate a preconfigured segue from within the application code. This can be achieved by assigning an identifier to the segue and then making a call to the performSegue withIdentifier: method of the view controller from which the segue is to be triggered.
Assuming a segue with the identifier of SegueToScene1, this could be triggered from within code as follows:. The Storyboard feature of Xcode allows for the navigational flow between the various views in an iOS application to be visually constructed without the need to write code. In this chapter we have covered the basic concepts behind storyboarding and worked through the creation of an example iOS application using storyboards and, in doing so, also explored the storyboard unwind feature.
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All Rights Reserved. Another great thing about writing your UI in code is its reusability. Just like with XIBs, you can reuse similar elements over and over again. Code makes it much easier to fix bugs and conflicts.
And this makes the UI harder to understand for new members of your development team. Our UI will contain two equal-sized square images placed side by side at the center of the screen. There will also be a label with a description below the images.
All UI elements and layout can be implemented without any code. For the left image:. For the right image:. For the label:. After we make our images the same size, we need to align them in the parent view in order to center them. Why use storyboards? Firstly, for prototyping and visualization. From our experience, the best way to use storyboards is alongside both XIBs and code. Each of these methods is good in different situations, and each helps you achieve different goals effectively.
You just need to know, when to use these tools in building the UI for your mobile app. Our website uses cookies to ensure you get the best experience. By browsing the website you consent to our Privacy and Cookies Policy. Pros and Cons of Working with Storyboards 5. Jul 27, Sveta Cherednichenko. Introduction When it comes to a new mobile app development project and user interface design , each iOS developer basically has to choose among these options for developing the UI: Write it in code from scratch Use XIBs Use storyboards Custom code is the classic approach to UI development, where everything from animations to positioning is handled in code.
What new features for developers did the iOS 13 update bring? What will change for users? Read in our review. Ecommerce development services. Are you planning to expand your business online? We will translate your ideas into intelligent and powerful ecommerce solutions.
Get a Free Consultation! Learn how to adapt your app for different markets. Subscribe to our newsletter. Rate the article! Latest articles. Nov 10, Nov 01, Oct 28, More articles. Share your project with us. Do experienced iOS developers use them?
Are any mainstream apps built with Storyboards? The short answer is yes, mainstream apps use Storyboards. Do all experienced developers use them? Another benefit to using Storyboards over creating views programmatically is that you get to see what your view will look like at runtime without having to run your app. And a third benefit is that you can create static table views in Storyboards.
So if you have a Settings screen, for example, with tappable rows of static text, Storyboards allow you to quickly and easily create them — no code required. If the benefits sound nice, consider the cons, too, before making a decision about whether to build your app with Storyboards.
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