lop jmenu trong java swing

http://vietjack.com/java_swing/index.jsp Copyright © vietjack.com Lớp JMenu Java Swing Mỗi cửa sổ window có trình đơn (menu bar) liên kết với Thanh trình đơn gồm lựa chọn có sẵn tới người dùng cuối Các điều khiển Menu MenuItem lớp lớp MenuComponent Lớp JMenu biểu diễn thành phần pull-down menu mà triển khai từ trình đơn Cú pháp khai báo cho lớp javax.swing.JMenu là: public class JMenu extends JMenuItem implements Accessible, MenuElement Lớp kế thừa phương thức từ lớp sau:  javax.swing.JAbstractButton  javax.swing.JComponent  java.awt.Container  java.awt.Component  java.lang.Object Lớp JMenu có trường protected JMenu.WinListener popupListener Các constructor lớp JMenu JMenu(): Xây dựng JMenu khơng có text JMenu(Action a): Xây dựng menu có thuộc tính nhận từ Action cho JMenu(String s): Xây dựng JMenu với chuỗi s cho (như text nó) JMenu(String s, boolean b): Xây dựng JMenu với chuỗi s cho (như text nó) giá trị boolean để xác định có hay khơng tear-off menu Chương trình ví dụ lớp JMenu SwingMenuDemo.java http://vietjack.com/ Trang chia sẻ học online miễn phí Page http://vietjack.com/java_swing/index.jsp Copyright © vietjack.com package com.vietjack.gui; import java.awt.*; import java.awt.event.*; public class SwingMenuDemo { private JFrame mainFrame; private JLabel headerLabel; private JLabel statusLabel; private JPanel controlPanel; public SwingMenuDemo(){ prepareGUI(); } public static void main(String[] args){ SwingMenuDemo swingMenuDemo = new SwingMenuDemo(); swingMenuDemo.showMenuDemo(); } private void prepareGUI(){ mainFrame = new JFrame("Vi du Java Swing"); mainFrame.setSize(400,400); mainFrame.setLayout(new GridLayout(3, 1)); headerLabel = new JLabel("",JLabel.CENTER ); statusLabel = new JLabel("",JLabel.CENTER); statusLabel.setSize(350,100); mainFrame.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent windowEvent){ System.exit(0); http://vietjack.com/ Trang chia sẻ học online miễn phí Page http://vietjack.com/java_swing/index.jsp Copyright © vietjack.com } }); controlPanel = new JPanel(); controlPanel.setLayout(new FlowLayout()); mainFrame.add(headerLabel); mainFrame.add(controlPanel); mainFrame.add(statusLabel); mainFrame.setVisible(true); } private void showMenuDemo(){ //tao mot menu bar final JMenuBar menuBar = new JMenuBar(); //tao cac menu JMenu fileMenu = new JMenu("File"); JMenu editMenu = new JMenu("Edit"); final JMenu aboutMenu = new JMenu("About"); final JMenu linkMenu = new JMenu("Links"); //tao cac item JMenuItem newMenuItem = new JMenuItem("New"); newMenuItem.setMnemonic(KeyEvent.VK_N); newMenuItem.setActionCommand("New"); JMenuItem openMenuItem = new JMenuItem("Open"); openMenuItem.setActionCommand("Open"); JMenuItem saveMenuItem = new JMenuItem("Save"); saveMenuItem.setActionCommand("Save"); http://vietjack.com/ Trang chia sẻ học online miễn phí Page http://vietjack.com/java_swing/index.jsp Copyright © vietjack.com JMenuItem exitMenuItem = new JMenuItem("Exit"); exitMenuItem.setActionCommand("Exit"); JMenuItem cutMenuItem = new JMenuItem("Cut"); cutMenuItem.setActionCommand("Cut"); JMenuItem copyMenuItem = new JMenuItem("Copy"); copyMenuItem.setActionCommand("Copy"); JMenuItem pasteMenuItem = new JMenuItem("Paste"); pasteMenuItem.setActionCommand("Paste"); MenuItemListener menuItemListener = new MenuItemListener(); newMenuItem.addActionListener(menuItemListener); openMenuItem.addActionListener(menuItemListener); saveMenuItem.addActionListener(menuItemListener); exitMenuItem.addActionListener(menuItemListener); cutMenuItem.addActionListener(menuItemListener); copyMenuItem.addActionListener(menuItemListener); pasteMenuItem.addActionListener(menuItemListener); final JCheckBoxMenuItem showWindowMenu = new JCheckBoxMenuItem("Show About", true); showWindowMenu.addItemListener(new ItemListener() { public void itemStateChanged(ItemEvent e) { if(showWindowMenu.getState()){ menuBar.add(aboutMenu); }else{ menuBar.remove(aboutMenu); } } http://vietjack.com/ Trang chia sẻ học online miễn phí Page http://vietjack.com/java_swing/index.jsp Copyright © vietjack.com }); final JRadioButtonMenuItem showLinksMenu = new JRadioButtonMenuItem("Show Links", true); showLinksMenu.addItemListener(new ItemListener() { public void itemStateChanged(ItemEvent e) { if(menuBar.getMenu(3)!= null){ menuBar.remove(linkMenu); mainFrame.repaint(); }else{ menuBar.add(linkMenu); mainFrame.repaint(); } } }); //them cac item toi cac menu fileMenu.add(newMenuItem); fileMenu.add(openMenuItem); fileMenu.add(saveMenuItem); fileMenu.addSeparator(); fileMenu.add(showWindowMenu); fileMenu.addSeparator(); fileMenu.add(showLinksMenu); fileMenu.addSeparator(); fileMenu.add(exitMenuItem); editMenu.add(cutMenuItem); editMenu.add(copyMenuItem); editMenu.add(pasteMenuItem); //them menu toi menubar menuBar.add(fileMenu); http://vietjack.com/ Trang chia sẻ học online miễn phí Page http://vietjack.com/java_swing/index.jsp Copyright © vietjack.com menuBar.add(editMenu); menuBar.add(aboutMenu); menuBar.add(linkMenu); //them menubar toi frame mainFrame.setJMenuBar(menuBar); mainFrame.setVisible(true); } class MenuItemListener implements ActionListener { public void actionPerformed(ActionEvent e) { statusLabel.setText(e.getActionCommand() + " JMenuItem clicked."); } } } http://vietjack.com/ Trang chia sẻ học online miễn phí Page ... bar final JMenuBar menuBar = new JMenuBar(); //tao cac menu JMenu fileMenu = new JMenu( "File"); JMenu editMenu = new JMenu( "Edit"); final JMenu aboutMenu = new JMenu( "About"); final JMenu linkMenu... private JPanel controlPanel; public SwingMenuDemo(){ prepareGUI(); } public static void main(String[] args){ SwingMenuDemo swingMenuDemo = new SwingMenuDemo(); swingMenuDemo.showMenuDemo(); } private...http://vietjack.com /java_ swing/ index.jsp Copyright © vietjack.com package com.vietjack.gui; import java. awt.*; import java. awt.event.*; public class SwingMenuDemo { private JFrame