我想知道
requestFocusInWindow()
和grabFocus()
方法之间的区别。在这个程序中,它们都可以很好地抓取焦点。因此,我不明白它们之间的区别。import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class Focus extends JFrame
{
JButton jb;
public Focus()
{
createAndShowGUI();
}
private void createAndShowGUI()
{
setTitle("grabFocus() vs requestFocusInWindow()");
setLayout(new FlowLayout());
setSize(400,400);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jb=new JButton("Open Dialog");
jb.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent ae)
{
showDialog();
}
});
add(jb);
}
private void showDialog()
{
JDialog jd=new JDialog();
jd.setLayout(new GridLayout(2,2));
jd.setVisible(true);
JLabel l1=new JLabel("Label 1");
JLabel l2=new JLabel("Label 2");
JTextField jt1=new JTextField(20);
JTextField jt2=new JTextField(20);
jd.add(l1);
jd.add(jt1);
jd.add(l2);
jd.add(jt2);
// Both of them are doing the thing
//jt2.grabFocus();
jt2.requestFocus();
jd.pack();
}
public static void main(String args[])
{
SwingUtilities.invokeLater(new Runnable(){
public void run()
{
new Focus();
}
});
}
}
requestFocusInWindow()
和grabFocus()
之间的区别,OP从未问过是否不应使用grabFocus()
。这是额外的信息。在StackOverflow上,没有附加信息的答案会被投票否决吗?我只是想知道!;) - JavaTechnical