Java课上的笔记，基础部分

一、菜单 1、菜单栏：JMenuBar 2、菜单:JMenu 3、菜单项:JMenuItem 将菜单项加入到菜单中；将菜单加入到菜单栏中； 将菜单栏加入到顶层容器中。 二、中间容器 JPanel：可以做容器，以分隔组件。 package cn.edu.jxau.soft; import java.awt.BorderLayout; import java.awt.FlowLayout; import java.awt.GridLayout; import java.awt.Image; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.ImageIcon; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JOptionPane; import javax.swing.JPanel; public class FirstFrame extends JFrame implements ActionListener{ private JPanel panel; private JButton[] button; private String[] strings = {"流式左", "流式右", "流式居中", "网格", "边界"}; private String[] BorderStrings = {"North", "South", "West", "East", "Center"}; private JMenuBar menuBar; private JMenu[] menu; private JMenuItem[] menuItems; public FirstFrame(){ this.setBounds(100, 100, 800, 600); setDefaultCloseOperation(HIDE_ON_CLOSE); setLayout(null); // setLayout(new FlowLayout(FlowLayout.LEFT)); // setLayout(new GridLayout(2, 3)); initCom(); initMenu(); setVisible(true); } /** * 初始化菜单 */ public void initMenu(){ menuBar = new JMenuBar(); menu = new JMenu[2]; menu[0]= new JMenu("操作"); menu[1]= new JMenu("帮助"); menuItems = new JMenuItem[5]; for (int i = 0; i < menuItems.length; i++) { menuItems[i] = new JMenuItem(strings[i]); menu[0].add(menuItems[i]); menuItems[i].addActionListener(this); } menuBar.add(menu[0]); menuBar.add(menu[1]); this.add(menuBar); menuBar.setBounds(0, 0, 800, 30); } public JButton[] getButton() { return button; } public void initCom(){ panel = new JPanel(); panel.setBounds(0, 30, 800, 530); this.add(panel); button = new JButton[5]; for (int i = 0; i < button.length; i++) { button[i] = new JButton(strings[i]); panel.add(button[i], BorderStrings[i]); button[i].addActionListener(this); //组件上加监听器，参数为监听器对象 } } public void addBorder(){ for (int i = 0; i < 5; i++) { panel.add(button[i], BorderStrings[i]); } } @Override /** * 当发生了点击事件，就会自动调用此方法 * arg0:事件 */ public void actionPerformed(ActionEvent arg0) { // TODO Auto-generated method stub if(arg0.getSource() == button[0] || arg0.getSource() == menuItems[0]){//getSource获取事件源 panel.setLayout(new FlowLayout(FlowLayout.LEFT)); }else{ if(arg0.getSource() == button[1] || arg0.getSource() == menuItems[1]){ panel.setLayout(new FlowLayout(FlowLayout.RIGHT)); }else{ if(arg0.getSource() == button[2] || arg0.getSource() == menuItems[2]){ panel.setLayout(new FlowLayout(FlowLayout.CENTER)); }else{ if(arg0.getSource() == button[3] || arg0.getSource() == menuItems[3]){ panel.setLayout(new GridLayout(2, 3)); }else{ if(arg0.getSource() == button[4] || arg0.getSource() == menuItems[4]){ panel.setLayout(new BorderLayout()); addBorder(); } } } } } validate();//让当前界面无效 } } 三、工具栏 1、工具栏：JToolBar; 2、图形按钮:JButton; 将图形按钮加入到工具栏，将工具栏加入到顶 层容器 package cn.edu.jxau.soft; import java.awt.BorderLayout; import java.awt.FlowLayout; import java.awt.GridLayout; import java.awt.Image; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.ImageIcon; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JToolBar; public class FirstFrame extends JFrame implements ActionListener{ private JPanel panel; private JButton[] button; private String[] strings = {"流式左", "流式右", "流式居中", "网格", "边界"}; private String[] BorderStrings = {"North" , "South", "West", "East", "Center"}; private JMenuBar menuBar; private JMenu[] menu; private JMenuItem[] menuItems; private JToolBar toolBar; private JButton[] imgButtons; private ImageIcon[] imgs = { new ImageIcon("copy.jpg"), new ImageIcon("cut.jpg") , new ImageIcon("find.jpg"), new ImageIcon("help.jpg") , new ImageIcon("new.jpg") }; public FirstFrame(){ this.setBounds(100, 100, 800, 600); setDefaultCloseOperation(HIDE_ON_CLOSE); setLayout(null); // setLayout(new FlowLayout(FlowLayout.LEFT)); // setLayout(new GridLayout(2, 3)); initCom(); initMenu(); initToolBar(); setVisible(true); } /** * 初始化菜单 */ public void initMenu(){ menuBar = new JMenuBar(); menu = new JMenu[2]; menu[0]= new JMenu("操作"); menu[1]= new JMenu("帮助"); menuItems = new JMenuItem[5]; for (int i = 0; i < menuItems.length; i++) { menuItems[i] = new JMenuItem(strings[i]); menu[0].add(menuItems[i]); menuItems[i].addActionListener(this); } menuBar.add(menu[0]); menuBar.add(menu[1]); this.add(menuBar); menuBar.setBounds(0, 0, 800, 30); } /** * 初始化工具栏 * */ public void initToolBar(){ toolBar = new JToolBar(); toolBar.setBounds(0, 30, 800, 30); this.add(toolBar); imgButtons = new JButton[5]; for (int i = 0; i < imgButtons.length; i++) { imgButtons[i] = new JButton(imgs[i]); imgButtons[i].addActionListener(this); imgButtons[i].setToolTipText(strings[i]); toolBar.add(imgButtons[i]); } } public JButton[] getButton() { return button; } public void initCom(){ panel = new JPanel(); panel.setBounds(0, 60, 800, 500); this.add(panel); button = new JButton[5]; for (int i = 0; i < button.length; i++) { button[i] = new JButton(strings[i]); panel.add(button[i], BorderStrings[i]); button[i].addActionListener(this); //组件上加监听器，参数为监听器对象 } } public void addBorder(){ for (int i = 0; i < 5; i++) { panel.add(button[i], BorderStrings[i]); } } @Override /** * 当发生了点击事件，就会自动调用此方法 * arg0:事件 */ public void actionPerformed(ActionEvent arg0) { // TODO Auto-generated method stub if(arg0.getSource() == button[0] || arg0.getSource() == menuItems[0] || arg0.getSource() == imgButtons[0]){//getSource获取事件源 panel.setLayout(new FlowLayout(FlowLayout.LEFT)); }else{ if(arg0.getSource() == button[1] || arg0.getSource() == menuItems[1] || arg0.getSource() == imgButtons[1]){ panel.setLayout(new FlowLayout(FlowLayout.RIGHT)); }else{ if(arg0.getSource() == button[2] || arg0.getSource() == menuItems[2] || arg0.getSource() == imgButtons[2]){ panel.setLayout(new FlowLayout(FlowLayout.CENTER)); }else{ if(arg0.getSource() == button[3] || arg0.getSource() == menuItems[3] || arg0.getSource() == imgButtons[3]){ panel.setLayout(new GridLayout(2, 3)); }else{ if(arg0.getSource() == button[4] || arg0.getSource() == menuItems[4] || arg0.getSource() == imgButtons[4]){ panel.setLayout(new BorderLayout()); addBorder(); } } } } } validate();//让当前界面无效 } }