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Discover how to effectively manage view visibility in your Android app, overcoming problems with `View.GONE` and ensuring your layouts behave as expected.
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This video is based on the question https://stackoverflow.com/q/69716781/ asked by the user 'Seth Harlaar' ( https://stackoverflow.com/u/7304712/ ) and on the answer https://stackoverflow.com/a/69804690/ provided by the user 'Jeevanandhan' ( https://stackoverflow.com/u/1501864/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

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How to Recover a View from View.GONE: Fixing Visibility Issues in Android

When developing Android applications, managing the visibility of views can sometimes lead to confusion, especially when working with the View.GONE attribute defined in XML. Many developers encounter situations where attempts to make a view visible using setVisibility(View.VISIBLE) fail despite the view being non-null. This guide addresses a common problem faced by developers and provides an in-depth solution to bring your views back to life after they’ve gone ‘gone’.

The Problem

You may find that after setting the visibility of your layout in XML to gone, your attempts to make it visible again in your adapter's onClick event do not yield any results. Specifically, the view you want to show doesn’t display despite your code seemingly indicating it should. A user named Seth faced this specific issue, prompting him to look for an effective solution to get his assess_list_layout to appear after clicking on the relevant parent layout.

Issue Explanation:

In Seth’s scenario, the layout tagged with android:id="@ + id/assess_list_layout" had its visibility initially set to gone. Though efforts were made to change its visibility to View.VISIBLE within the list item click event of the adapter, nothing happened. The layout worked perfectly when it was set to invisible, leading to the conclusion that the initial rendering was problematic when using gone.

The Solution

Step 1: Adjust Your XML Layout

Remove the android:visibility="gone" line from your XML file. By doing this, you allow the view to be rendered even when it is not displayed. You will control the visibility entirely through your code.

Here’s how your assess_list_layout should look:

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Step 2: Hardcode Layout Height

Ensure the layout height is hardcoded (for example, 300dp), this provides the layout with initial size, allowing it to be rendered. As the ListView is managed separately, you can handle its display in the adapter itself, which facilitates smooth transitions.

Step 3: Manage Visibility Using a Model Class

Introduce a boolean property to your Course class that will help manage the selected state of the courses. By setting isSelected to false by default, you can determine whether to show the assess layout when a particular item is clicked.

Here’s an example of how the Course class should look:

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Step 4: Modify the Adapter Class

In your CourseListAdapter, you need to implement logic in the getView method to check the selection status of each item. Here’s an excerpt of the changes that need to be made:

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

Key Takeaways

Begin with Clear Visibility Control: Don’t rely on XML to set initial visibility when dynamic interaction is required. Control all relevant changes programmatically within your adapter.

Model State Management: Implement boolean properties within your model classes to help track which views should currently be displayed or hidden.

Ensure Proper Layout Rendering: Make sure layouts are appropriately sized and configured to display as needed when activated programmatically.

By following these steps, you should be able to smoothly recover views from being gone and ensure both UI integrity and a pleasant user experience!

If you need further assistance or have other suggestions for handling view visibility during Android development, don’t hesitate to ask. Happy coding!