1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
| import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TextDemo extends JPanel implements ActionListener {
private JTextField textField;
private JTextArea textArea;
private final static String newline = "\n";
public TextDemo() {
super(new GridBagLayout());
textField = new JTextField(40);
textField.addActionListener(this);
textArea = new JTextArea(15, 40);
textArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(textArea);
//Add Components to this panel.
GridBagConstraints c = new GridBagConstraints();
c.gridwidth = GridBagConstraints.REMAINDER;
c.fill = GridBagConstraints.BOTH;
c.weightx = 1.0;
c.weighty = 1.0;
add(scrollPane, c);
c.fill = GridBagConstraints.HORIZONTAL;
add(textField, c);
}
public void actionPerformed(ActionEvent evt) {
String text = textField.getText();
textArea.append(text + newline);
textField.selectAll();
//Make sure the new text is visible, even if there
//was a selection in the text area.
textArea.setCaretPosition(textArea.getDocument().getLength());
}
public void addText(String text) {
textArea.setText(text);
textArea.setCaretPosition(textArea.getDocument().getLength());
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event dispatch thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("TextDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Add contents to the window.
frame.add(new TextDemo());
//Display the window.
frame.pack();
frame.setVisible(true);
}
public void run() {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
} |
