Duplicate globalkey detected in widget tree.

The error message “duplicate global key detected in widget tree” indicates that there are multiple instances of a widget with the same global key in your Flutter application’s widget tree. Each widget in Flutter can be identified by a unique key, and using the same key for multiple widgets causes conflicts and leads to this error.

To fix this issue, you need to ensure that each widget in your widget tree has a unique global key. The global key is typically used to identify widgets that maintain state, such as Form, TextField, or PageView. It allows Flutter to keep track of the state changes and rebuild only specific parts of the widget tree when necessary.

Example:

Let’s consider a scenario where you have a ListView widget that displays a list of items using ListTile widgets. Each ListTile represents a unique item and should have a unique key:

        
            ListView(
              children: [
                ListTile(
                  key: Key('item_1'),
                  title: Text('Item 1'),
                ),
                ListTile(
                  key: Key('item_2'),
                  title: Text('Item 2'),
                ),
                ListTile(
                  key: Key('item_3'),
                  title: Text('Item 3'),
                ),
              ],
            )
        
    

In the above example, each ListTile has a unique key defined using the Key class, such as Key(‘item_1’), Key(‘item_2’), and Key(‘item_3’). This ensures that each ListTile is treated separately by Flutter and avoids the “duplicate global key” error.