Скачать или смотреть Troubleshooting Your Android RecyclerView: Why Your Items Are Not Showing Up!

Learn how to fix common issues with your Android RecyclerView when items are not displaying. Discover the simple mistake that can result in empty lists and how to resolve it quickly!
---
This video is based on the question https://stackoverflow.com/q/69868666/ asked by the user 'johneggo' ( https://stackoverflow.com/u/17346191/ ) and on the answer https://stackoverflow.com/a/69869002/ provided by the user 'avalerio' ( https://stackoverflow.com/u/2398000/ ) 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: RecyclerView Item not showing

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.
---
Troubleshooting Your Android RecyclerView: Why Your Items Are Not Showing Up!

If you're developing an Android application using RecyclerView, you might encounter situations where your items do not show up on the screen, even after you've set everything up correctly. This can be frustrating, especially after spending time crafting your RecyclerView and its adapter. In this guide, we'll explore a common cause of this issue and how to resolve it with clear, actionable steps.

Understanding the Problem

You may have set up your RecyclerView and its adapter, populated it with data, yet nothing shows up when you run your app. This problem typically arises not from the layout itself but from how your data is being handled in the adapter.

The Solution: Binding Data Correctly

The main reason why items in the RecyclerView may not appear is that the adapter's getItemCount() method is returning zero. This method tells the RecyclerView how many items it needs to display. If it returns zero, the RecyclerView will reflect that by showing nothing.

Steps to Fix the Issue

Locate the Adapter: Open your adapter class (NotificationPanelRecViewAdapter in this case) and check the implementation of the getItemCount() method.

Here's the original, incorrect implementation:

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

Update the Method: Change getItemCount() to return the size of your data list (notificationPanel). This will allow the RecyclerView to know how many items exist.

Update the method to look like this:

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

Verify Data Population: Ensure that the data is actually being populated in your RecyclerView. In MainActivity, when you create instances of NotificationPanel, you're already doing this correctly with:

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

Set the Adapter: Confirm that you have set the adapter for the RecyclerView after populating it with data, which you seem to have done correctly:

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

Run Your App: After making the above changes, re-run your application to check if your items appear in the RecyclerView.

Conclusion

When dealing with RecyclerView in Android development, it’s crucial to properly implement data binding through the adapter. A common oversight is forgetting to return the correct item count, leading to an empty display. By ensuring getItemCount() reflects the actual size of your data set, you'll allow the RecyclerView to function as intended.

By following the steps outlined in this guide, you should be able to fix the issue of RecyclerView items not appearing in your app. Happy coding, and may your lists be ever populated!