How to Effectively Create a GlobalKey List Using list.generate Method in Flutter

---

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---

Creating multiple widgets in Flutter and needing to reference them can bring challenges, especially when it comes to maintaining their states and accessing their coordinates. One robust way to do this is by utilizing GlobalKey. However, if misconfigured, you may encounter issues like a stack overflow error. In this post, we will walk through a common scenario where you might want to generate a list of GlobalKeys and show you how to do it correctly.

The Problem

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

What Went Wrong?

The code causes a stack overflow because you are trying to reference keyCap while the list is still being constructed. You're creating a circular dependency as each item tries to assign itself within the list while it’s still being defined.

To create a list of GlobalKeys without errors, you'll want to avoid trying to assign a key to itself during its creation. Instead, you can directly instantiate a new GlobalKey for each element of the list. Here’s how you can do it correctly:

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

Breakdown of the Solution

Avoid Circular Reference: Instead of trying to assign keyCap[index], directly instantiate a new GlobalKey for each index.

Debug Label: Adding a debugLabel helps in identifying keys during debugging, making it easier to track each key.

Growable: Setting growable: false makes the list static, which is often a good practice when you don’t plan to change the size of the list after creation.

Updated Home Page Example

With the corrected list, you can now integrate these keys into your widgets seamlessly. A simple Flutter page using this updated method might look like this:

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

Conclusion

Remember, the goal is to not only solve the problem but also to understand the mechanics behind it to prevent similar issues in the future. Happy coding!