Transferring focus from new jFrame to previous jFrame

问题

I have two JFrames jFrame1 and jFrame2,in jFrame1 there's a textfield and a button,while clicking on button jFrame2 will appear. In jFrame2 there's also a textfield and a button.I will type a name in textfield of jFrame2 and by clicking the button in it that textfield value should appear on textfield of jFrame1. But I am not getting the focus transferred to jFrame1,i tried the code,

in jFrame1

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
        jFrame2 abc=new jFrame2();
        abc.setVisible(true);
    }   


public void inserting(String name){
   jTextField1.requestFocusInWindow();
   jTextField1.setText(name);

 }

in jFrame2,

 private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         

        jFrame1 abc1=new jFrame1();
       // abc1.transferFocus();  //not working

        abc1.inserting(jTextField1.getText());
        this.dispose();
    }

I am getting value to the method inserting(),but it's not getting set into the textfield. If I again give setVisible(true) for jFrame1 it works,but I dont want to do i in that way. Is there any other way to resolve this?

回答1:

To bring focus to the field, you should use requestFocusInWindow, however I don't think that will bring the window in question back into focus.

You could use a WindowListener to monitor changes that you could respond.

For example, in jFrame1's actionPerformed handler you could

Frame02 frame2 = new Frame02();
frame2.addWindowListener(new WindowAdapter() {

    @Override
    public void windowClosed(WindowEvent we) {

        Frame02 frame2 = (Frame02) we.getWindow();
        jTextField1.setText(frame2.getText());

        toFront();
        jTextField1.requestFocusInWindow();

    }

});

frame2.setVisible(true);
frame2.toFront();
frame2.requestFocus();

jFrame1 is requesting the text from jFrame2 cause jFrame2 doesn't know about jFrame1, there's no reference to it.

In jFrame2 you would need to add a WindowListener to handle the request for focus of the text field

addWindowListener(new WindowAdapter() {
    public void windowOpened(WindowEvent we) {
        jTextField1.requestFocus();
    }
});

回答2:

If you're using your second frame to just take a user's input, why not switch to using a JOptionPane.showInputDialog()? You can configure this to give you a TextField and a Button and returns a String? Use this value to set the value of the JTextField in your first frame.

So your first method would be something like this:

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    String inputString = JOptionPane.showInputDialog(this, "Enter Value: ");
    jTextField1.setText(inputString);
}

I think this one would be a simpler solution instead of working with a couple of frames and switching focus in between them.

This tutorial about "Getting the User's Input from a Dialog" might help you get a better picture about using Input Dialog.

来源：https://stackoverflow.com/questions/11982650/transferring-focus-from-new-jframe-to-previous-jframe

标签

java

swing

jframe