What is the TextEditingController?
Why Interviewers Ask This
Interviewers use this question to quickly assess whether a candidate has the foundational knowledge required for Flutter development. It reveals whether you understand the building blocks that more complex concepts rely on.
Answer
TextEditingController is used to read, write, and listen to changes in a TextField. Assign it to the controller property of the TextField. Read the current text with controller.text, set text with controller.text = "new value", and listen for changes by adding a listener: controller.addListener(() { ... }). Always call controller.dispose() in the widget's dispose() method to free resources and prevent memory leaks.
Pro Tip
Before answering, structure your response: one-line definition → real-world analogy → concrete example from a project. This makes even complex Flutter answers easy to follow.