Java EventHandler for a TexBox that Acts Whenever any Letter is Pressed?

I have a variable that I want to write to from a textbox, but I want it to be written to automatically when the user types the text into it... Is the开发者_如何学编程re an EventHandler to do this, or do I have to do something different?

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I believe you can use a Key Listener for that:

Key Listener

Go ahead and add a key listener to your textfield.