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Learn how to solve the issue of using two keys with `Scaffold` and `ScaffoldMessenger` in Flutter to successfully show a snackbar.
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How to Use Scaffold and ScaffoldMessenger Together in Flutter

When developing applications using Flutter, you may encounter a scenario where you want to utilize both Scaffold and ScaffoldMessenger. A common issue is prompting a snackbar to show up using showSnackBar() method while correctly managing the state with two distinct keys: _scaffoldStateKey for Scaffold and _scaffoldMessengerKey for ScaffoldMessenger.

In this guide, we will explore how to effectively implement both keys so that you can successfully display a snackbar in your Flutter app. Let’s dive into the solution!

Understanding the Problem

The initial attempt to show a snackbar may resemble this code snippet:

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

In this case, you are trying to use _scaffoldMessengerKey to call showSnackBar(), but the method fails because ScaffoldMessenger needs to wrap the Scaffold. Without properly organizing these components, the snackbar won’t appear, leading to confusion and frustration.

The Solution: Properly Nesting the Widgets

To resolve this issue, you need to correctly nest the ScaffoldMessenger within the build method while making sure it establishes the necessary relationship among your keys.

Here’s an improved version of the code:

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

Key Adjustments Made:

Wrapping the Scaffold: The Scaffold widget is now wrapped inside a ScaffoldMessenger, which allows it to manage the snackbar correctly.

Using GlobalKey: The _scaffoldMessengerKey provides a context for the ScaffoldMessenger to track changes and display the snackbar as expected.

Clear Structure: This structure maintains a clean separation between the drawer and the snackbar functionality, allowing both to work simultaneously.

Conclusion

In Flutter, effectively using Scaffold and ScaffoldMessenger simultaneously requires proper alignment and nesting. By ensuring that the Scaffold is wrapped in the ScaffoldMessenger, you can manage both the drawer and snackbar effortlessly.

Now, you can enhance your Flutter applications with interactive features without worrying about unexpected behaviors. Happy coding!