一般类的成员变量都应设成private的。
所以你只需要在 class aa这么写
class aa{
JTextArea text = new JTextArea; public void setText(String strText) {
text.setText(strText) ;
}}再class bb 里写个函数调用他。class bb{
public void f() { aa obja = new aa() ;
obja.setText("test"); }}
所以你只需要在 class aa这么写
class aa{
JTextArea text = new JTextArea; public void setText(String strText) {
text.setText(strText) ;
}}再class bb 里写个函数调用他。class bb{
public void f() { aa obja = new aa() ;
obja.setText("test"); }}
如果是的public,
类b就通过a的对象来访问,
如果是private,
就在a中写个方法setA()来访问,
在类b中掉用对像a的setA()的方法来访问!
不过建议把成员变量设成private,这样才有安全性
java里大都是把成员变量设成private
然后提供 Getter函数和setter 函数访问他们
import javax.swing.*;
import java.awt.event.*;
import javax.swing.border.*;
import java.util.*;private class TJFrame extends JFrame
{
Container container = null;
JTextArea textarea; public TJFrame (String title)
{
super(title);
container = this.getContentPane();
container.setBackground(Color.white);
container.setForeground(Color.blue);
JLabel label = new JLabel("this is a swing frame",JLabel.CENTER);
label.setFont(new Font("Sans",Font.PLAIN,22));
container.add(label); JMenuBar menubar = new JMenuBar();
menubar.setBorder(new BevelBorder(BevelBorder.RAISED));
container.add(menubar,BorderLayout.NORTH);
JMenu filemenu = new JMenu("File");
JMenu newfilemenu = new JMenu("New");
JMenu editmenu = new JMenu("Edit");
JMenu formatmenu = new JMenu("View");
JMenu searchmenu = new JMenu("Search");
JMenu windowmenu = new JMenu("Window");
JMenu optionsmenu = new JMenu("Option");
JMenu helpmenu = new JMenu("Help"); textarea = new JTextArea();
container.add(textarea);
textarea.setText("niaho");
JMenuItem txt = new JMenuItem("Text");
Action php = new phpAction(container);
JMenuItem java = new JMenuItem("Java");
JMenuItem open = new JMenuItem("Open");
JMenuItem save = new JMenuItem("Save");
JMenuItem close = new JMenuItem("Close");
Action quit = new QuitAction(); filemenu.add(newfilemenu);
newfilemenu.add(txt);
newfilemenu.add(php);
newfilemenu.add(java);
filemenu.add(open);
filemenu.add(save);
filemenu.add(close);
filemenu.add(quit);
menubar.add(filemenu);
menubar.add(editmenu);
menubar.add(formatmenu);
menubar.add(searchmenu);
menubar.add(windowmenu);
menubar.add(optionsmenu);
menubar.add(helpmenu); addWindowListener(new WindowEventHandler());
setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
setSize(650,500);
show();
} public static void main(String[] args)
{
TJFrame frame = new TJFrame("Swing frame");
} public void setText(String strText) {
textarea.setText(strText) ;
}
}class WindowEventHandler extends WindowAdapter
{
public void windowClosing(WindowEvent evt)
{
System.exit(0);
}
}class QuitAction extends AbstractAction
{
public QuitAction()
{
super("Quit");
}
public void actionPerformed(ActionEvent e)
{
System.out.print(e.getActionCommand());
System.exit(0);
}
}class phpAction extends AbstractAction
{
public phpAction(Container container)
{
super("PHP");
}
public void actionPerformed(ActionEvent e)
{
//JFrame n = new JFrame("test");
//n.addWindowListener(new WindowEventHandler());
//n.setSize(300,150);
//n.show();
f();
}
public void f()
{
TJFrame obja = new TJFrame() ;
obja.setText("test");
}
}