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java - How to detect backspace in a keyTypedEvent

I'm using Netbeans' bean form to create my GUI.
I've added a keyTyped event to a JTextArea and I want to detect if the typed key is a Backspace.

I'm using keyTyped event for other reasons so I cannot just use the keyPressed event.

This is the generated code (and my if check):

private void langArea1KeyTyped(java.awt.event.KeyEvent evt) {   

    if(evt.getChar()== backspace) //how can I make this check?   
}     

evt.getKeyCode() always returns 0 independent of the typed key.
evt.getKeyChar() simply deletes the last character printed when printed so I can't use System.out.print(evt.getKeyChar()) to detect its value and check for it.

How can I detect if the typed key is Backspace (or Delete)?

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1 Answer

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You cannot use keyTyped, you need to use either keyPressed or keyReleased to determine if backspace character has been typed. The keyTyped event only picks up non-escape characters (only characters that can be displayed).

The backspace character can be checked with KeyEvent.VK_BACK_SPACE.

Try adding this listener to the keyPressed event:

import java.awt.event.KeyEvent;

private void langArea1KeyPressed(KeyEvent evt) {   
    if (evt.getKeyCode() == KeyEvent.VK_BACK_SPACE) {
        // Do something...
    }
}

Additional Reading

You can check out the official Java tutorial on How to Write a Key Listener.


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