The following illustrates use of TextListener with AWT TextField. TextListener listens to TextEvent which is generated when the text in a text component (a TextField or TextArea) changes.
The
TextFieldTextEvent(): This contains code illustrating the use of TextListener with AWT TextField.
new TextFieldTextEvent(): This creates object for the class.
Next: Using MouseListener for AWT Frame
import java.awt.*;
import java.awt.event.*;
class TextFieldTextEvent extends Frame implements TextListener
{
TextField t;
public TextFieldTextEvent()
{
createAndShowGUI();
}
private void createAndShowGUI()
{
setTitle("TextListener for TextField");
setLayout(new FlowLayout());
// Create textfield that shows upto 20 chars
t=new TextField(20);
// This object is object of TextListener since
// it implements TextListener
t.addTextListener(this);
add(t);
setSize(400,400);
setVisible(true);
}
// Called whenever the text in a text component (here t) changes
public void textValueChanged(TextEvent te)
{
// Update the frame title
setTitle(t.getText());
}
public static void main(String args[])
{
new TextFieldTextEvent();
}
}
The
TextEvent
class doesn't contain methods to get the text because you have them in the TextField
class. This event is fired only when there is a change in the text (either deletion,addition). This is much similar to DocumentEvent in swing but unlike in DocumentListener
, TextListener doesn't have separate methods (handlers) for insertion and deletion.TextFieldTextEvent(): This contains code illustrating the use of TextListener with AWT TextField.
new TextFieldTextEvent(): This creates object for the class.
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