jtextfielddemo.java

Swing入门必看 Swing Demo

package components;

import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextArea;
import javax.swing.JTextField;

public class JTextFieldDemo extends JFrame {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	private JTextArea textArea;

	private JTextField[] fields;

	private JPasswordField[] pwds;

	public JTextFieldDemo() {
		Container container = getContentPane();
		container.setLayout(new FlowLayout());

		JPanel textPanel = new JPanel();
		JPanel pwdPanel = new JPanel();

		fields = new JTextField[6];
		fields[0] = new JTextField();
		fields[1] = new JTextField("String");
		fields[2] = new JTextField(10);
		fields[3] = new JTextField("String", 10);
		
		fields[3].setBackground(Color.RED);
		fields[3].setActionCommand("i love you");
		pwds = new JPasswordField[6];

		pwds[0] = new JPasswordField();
		pwds[1] = new JPasswordField("String");
		pwds[2] = new JPasswordField(10);
		pwds[3] = new JPasswordField("String", 10);

		TextActionListener listener = new TextActionListener();
		for (int i = 0; i < 4; i++) {
			fields[i].addActionListener(listener);
			pwds[i].addActionListener(listener);
			textPanel.add(fields[i]);
			pwdPanel.add(pwds[i]);
		}
		container.add(textPanel);
		container.add(pwdPanel);
		textArea = new JTextArea(14, 22);
		container.add(textArea);

		setSize(400, 400);
		setVisible(true);

	}

	class TextActionListener implements ActionListener {

		public void actionPerformed(ActionEvent e) {
			if (e.getSource() == fields[0]) {
				textArea.setText("fields[0] :\n text: " + fields[0].getText()
						+ "\n selected text " + fields[0].getSelectedText());
			} else if (e.getSource() == fields[1]) {
				textArea.setText("fields[1] :\n text: " + fields[1].getText()
						+ "\n selected text " + fields[1].getSelectedText());
			} else if (e.getSource() == fields[2]) {
				textArea.setText("fields[2] :\n text: " + fields[2].getText()
						+ "\n selected text " + fields[2].getSelectedText());
			} else if (e.getSource() == fields[3]) {
				textArea.setText("fields[3] :\n text: " + e.getActionCommand()
						+ "\n selected text " + fields[3].getSelectedText());
			} else if (e.getSource() == pwds[0]) {
				textArea.setText("pwds[0] :\n text: " + new String(pwds[0].getPassword())
						+ "\n selected text " + pwds[0].getSelectedText());
			} else if (e.getSource() == pwds[1]) {
				textArea.setText("pwds[1] :\n text: " + new String(pwds[1].getPassword())
						+ "\n selected text " + pwds[1].getSelectedText());
			} else if (e.getSource() == pwds[2]) {
				textArea.setText("pwds[2] :\n text: " + new String(pwds[2].getPassword())
						+ "\n selected text " + pwds[2].getSelectedText());
			} else if (e.getSource() == pwds[3]) {
				textArea.setText("pwds[3] :\n text: " + e.getActionCommand()
						+ "\n selected text " + pwds[3].getSelectedText());
			}

		}

	}

	public static void main(String[] args) {
		JTextFieldDemo application = new JTextFieldDemo();
		application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

	}

}