你没把ta加到Frame中去。应该加上这句:f.add(ta);
import java.awt.*;
import java.awt.event.*;
public class FileDialogExample implements ActionListener{
Frame f;
Button b;
TextArea ta;
FileDialog fd;
static public void main(String args[]){
FileDialogExample fde=new FileDialogExample();
fde.go();
}
public void go(){
f=new Frame("FileDialog Example");
b=new Button("show filedialog");
b.addActionListener(this);
f.add("South",b);
ta=new TextArea();
f.add(ta); //
fd=new FileDialog(f,"FileDialog");
f.setSize(350,150);
f.setVisible(true);
}
public void actionPerformed(ActionEvent e){
fd.setVisible(true);
ta.append("Directory: "+fd.getDirectory());
ta.append("\nFilename: "+fd.getFile());
}
}
import java.awt.*;
import java.awt.event.*;
public class FileDialogExample implements ActionListener{
Frame f;
Button b;
TextArea ta;
FileDialog fd;
static public void main(String args[]){
FileDialogExample fde=new FileDialogExample();
fde.go();
}
public void go(){
f=new Frame("FileDialog Example");
b=new Button("show filedialog");
b.addActionListener(this);
f.add("South",b);
ta=new TextArea();
f.add(ta); //
fd=new FileDialog(f,"FileDialog");
f.setSize(350,150);
f.setVisible(true);
}
public void actionPerformed(ActionEvent e){
fd.setVisible(true);
ta.append("Directory: "+fd.getDirectory());
ta.append("\nFilename: "+fd.getFile());
}
}
import java.awt.*;
import java.awt.event.*;
public class FileDialogExample implements ActionListener{
Frame f;
Button b;
TextArea ta;
FileDialog fd;
static public void main(String args[]){
FileDialogExample fde=new FileDialogExample();
fde.go();
}
public void go(){
f=new Frame("FileDialog Example");
b=new Button("show filedialog");
b.addActionListener(this);
f.add("South",b);
ta=new TextArea();
f.add("Center",ta);//note this
fd=new FileDialog(f,"FileDialog");
f.setSize(350,150);
f.setVisible(true);
}
public void actionPerformed(ActionEvent e){
fd.setVisible(true);
ta.append("Directory: "+fd.getDirectory());
ta.append("\nFilename: "+fd.getFile());
}
}