运用Java编写文本编辑器程序
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class EditorJFrame extends JFrame implements ActionListener, MouseListener
{
private JComboBox combox_name, combox_size; //字体、字号组合框
private JCheckBox checkb_bold, checkb_italic; //粗体、斜体复选框
private JRadioButton radiob_color[]; //颜色单选按钮
private JTextArea text; //文本区
private Color color; //text的当前文本色
private JPopupMenu popupmenu; //快捷菜单
public EditorJFrame()
{
super("文本编辑器"); //默认BorderLayout布局
Dimension dim = getToolkit().getScreenSize(); //获得屏幕分辨率
this.setBounds(dim.width/4,dim.height/4,dim.width/2,dim.height/2); //窗口居中
this.setDefaultCloseOperation(EXIT_ON_CLOSE); //窗口关闭时，程序结束
text = new JTextArea("Welcome 欢迎");
text.addMouseListener(this); //文本区注册鼠标事件监听器
this.getContentPane().add(new JScrollPane(text)); //文本区添加到滚动窗格，滚动窗格添加到框架内容窗格中部
JToolBar toolbar=new JToolBar(); //创建工具栏，默认水平方向
this.getContentPane().add(toolbar,"North"); //工具栏添加到框架内容窗格北部
GraphicsEnvironment ge=GraphicsEnvironment.getLocalGraphicsEnvironment();
String[] fontsName=ge.getAvailableFontFamilyNames(); //获得系统字体
combox_name = new JComboBox(fontsName); //组合框显示系统字体
combox_name.addActionListener(this); //组合框注册单击事件监听器
toolbar.add(combox_name);
String sizestr[]={"20","30","40","50","60","70"};
combox_size = new JComboBox(sizestr); //字号组合框
combox_size.setEditable(true); //设置组合框可编辑
combox_size.addActionListener(this); //组合框注册单击事件监听器
toolbar.add(combox_size);
checkb_bold = new JCheckBox("粗体"); //字形复选框
toolbar.add(checkb_bold);
checkb_bold.addActionListener(this); //复选框注册单击事件监听器
checkb_italic = new JCheckBox("斜体");
toolbar.add(checkb_italic);
checkb_italic.addActionListener(this);
String colorstr[]={"红","绿","蓝"};
ButtonGroup bgroup_color = new ButtonGroup(); //按钮组
radiob_color = new JRadioButton[colorstr.length]; //颜色单选按钮数组
for (int i=0; i<radiob_color.length; i++)
{
radiob_color[i]=new JRadioButton(colorstr[i]); //颜色单选按钮
radiob_color[i].addActionListener(this);
bgroup_color.add(radiob_color[i]); //单选按钮添加到按钮组
toolbar.add(radiob_color[i]); //单选按钮添加到工具栏
}
radiob_color[0].setSelected(true); //设置单选按钮的选中状态
this.addmyMenu(); //调用自定义方法，添加菜单
this.setVisible(true);
// String password = JOptionPane.showInputDialog(this, "密码");
// System.out.println(password); //单击"撤消"按钮返回null
}
private void addmyMenu() //添加主菜单、快捷菜单、对话框
{
JMenuBar menubar = new JMenuBar(); //菜单栏
this.setJMenuBar(menubar); //框架上添加菜单栏
String menustr[]={"文件","编辑","帮助"};
JMenu menu[]=new JMenu[menustr.length];
for (int i=0; i<menustr.length; i++)
{
menu[i] = new JMenu(menustr[i]); //菜单
menubar.add(menu[i]); //菜单栏中加入菜单
}
menu[0].add(new JMenuItem("打开")); //生成菜单项并加入到菜单
menu[0].add(new JMenuItem("保存"));
menu[0].addSeparator(); //加分隔线
JMenuItem menuitem_exit = new JMenuItem("退出");
menu[0].add(menuitem_exit);
menuitem_exit.addActionListener(this); //菜单项注册单击事件监听器
JMenu menu_style = new JMenu("字形");
menu_style.add(new JCheckBoxMenuItem("粗体"));
menu_style.add(new JCheckBoxMenuItem("斜体"));
/* String stylestr[]={"粗体", "斜体"};
JCheckBoxMenuItem cbmenuitem_style[]=new JCheckBoxMenuItem[stylestr.length];
for (int i=0; i<cbmenuitem_style.length; i++)
{
cbmenuitem_style[i] = new JCheckBoxMenuItem(stylestr[i]); //字形复选菜单项
cbmenuitem_style[i].addItemListener(this);
menu_style.add(cbmenuitem_style[i]);
}*/
menu[1].add(menu_style); //菜单加入到菜单中成为二级菜单
JMenu menu_color = new JMenu("颜色");
menu[1].add(menu_color);
ButtonGroup buttongroup = new ButtonGroup(); //按钮组
String colorstr[]={"红","绿","蓝"};
JRadioButtonMenuItem rbmi_color[]=new JRadioButtonMenuItem[colorstr.length];
for (int i=0; i<rbmi_color.length; i++)
{
rbmi_color[i] = new JRadioButtonMenuItem(colorstr[i]); //单选菜单项
buttongroup.add(rbmi_color[i]); //单选菜单项添加到按钮组
rbmi_color[i].addActionListener(this);
menu_color.add(rbmi_color[i]); //单选菜单项添加到菜单
}
popupmenu = new JPopupMenu(); //快捷菜单对象
String menuitemstr[]={"剪切","复制","粘贴"};
JMenuItem popmenuitem[] = new JMenuItem[menuitemstr.length];
for (int i=0; i<popmenuitem.length; i++)
{
popmenuitem[i] = new JMenuItem(menuitemstr[i]); //菜单项
popupmenu.add(popmenuitem[i]); //快捷菜单加入菜单项
popmenuitem[i].addActionListener(this);
}
popmenuitem[0].setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X, InputEvent.CTRL_MASK));//设置快捷键Ctrl+X
popmenuitem[1].setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C, InputEvent.CTRL_MASK));//设置快捷键Ctrl+C
popmenuitem[2].setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V, InputEvent.CTRL_MASK));//设置快捷键Ctrl+V
text.add(popupmenu); //文本区添加快捷菜单
}
public void actionPerformed(ActionEvent e) //单击事件处理方法
{
if (e.getSource() instanceof JRadioButton) //选择一个颜色复选框
{
if (e.getSource()==radiob_color[0])
color = new Color(255,0,0);
if (e.getSource()==radiob_color[1])
color = new Color(0,255,0);
if (e.getSource()==radiob_color[2])
color = new Color(0,0,255);
text.setForeground(color); //设置文本区颜色
return;
}
if (e.getSource() instanceof JMenuItem) //单击菜单项
{
if (e.getActionCommand()=="退出")
if (JOptionPane.showConfirmDialog(this, "终止当前程序运行？")==0)
System.exit(0); //单击确认对话框中的“是”按钮，结束程序运行
if (e.getActionCommand()=="剪切")
text.cut(); //将选中文本剪切送系统剪贴板
if (e.getActionCommand()=="复制")
text.copy(); //将选中文本复制送系统剪贴板
if (e.getActionCommand()=="粘贴")
text.paste(); //将剪贴板的文本粘贴在当前位置
return;
}
if (e.getSource() instanceof JComboBox || e.getSource() instanceof JCheckBox)
{ //组合框、复选框
int size=0;
try
{
String fontname = (String)combox_name.getSelectedItem();//获得字体名
size = Integer.parseInt((String)combox_size.getSelectedItem());//获得字号
if (size<4 || size>120) //字号超出指定范围时，抛出异常对象
throw new Exception("SizeException");
java.awt.Font font = text.getFont(); //获得文本区的当前字体对象
int style = font.getStyle(); //获得字形
if (e.getSource()==checkb_bold) //粗体
style = style ^ 1; //整数的位运算，异或^
if (e.getSource()==checkb_italic) //斜体
style = style ^ 2;
text.setFont(new Font(fontname, style, size)); //设置文本区字体
}
catch(NumberFormatException nfe)
{
JOptionPane.showMessageDialog(this, "\""+(String)combox_size.getSelectedItem()+"\" 不能转换成整数，请重新输入!");
}
catch(Exception ex)
{
if (ex.getMessage()=="SizeException") //捕获自己抛出的异常对象
JOptionPane.showMessageDialog(this, size+" 字号不合适，请重新输入!");
}
finally{}
}
if (e.getSource()==combox_size) //单击字号组合框
{ //将新输入的字号添加到组合框的下拉列表中，先要查找，不添加重复值
String size = (String)combox_size.getSelectedItem();//获得当前输入数据
int i=0, n=combox_size.getItemCount(); //n获得组合框的选项数
while (i<n && size.compareTo((String)combox_size.getItemAt(i))>=0)
{ //size与组合框的选项比较
if (size.compareTo((String)combox_size.getItemAt(i))==0)
return ; //相同，不插入
i++;
}
combox_size.insertItemAt(size, i); //将size插入在组合框的第i项
}
}
public void mouseClicked(MouseEvent mec) //鼠标事件处理方法，实现MouseListener接口
{
if (mec.getModifiers()==MouseEvent.BUTTON3_MASK) //单击的是鼠标右键
popupmenu.show(text,mec.getX(),mec.getY()); //在鼠标单击处显示快捷菜单
}
public void mousePressed(MouseEvent mep) {}
public void mouseReleased(MouseEvent mer) {}
public void mouseEntered(MouseEvent mee) {}
public void mouseExited(MouseEvent mex) {}
public void mouseDragged(MouseEvent med) {}
public static void main(String arg[])
{
new EditorJFrame();
}
}
