jFrame jumps in middle if the screen after jFrame.setLocation(Point p)

Question

Iám facing a litte problem here.

I tried to save the actual position of an jFrame, and restore this position after creating this frame again.

Heres the "save"-procedure:

private void formWindowClosing(java.awt.event.WindowEvent evt) {                                   
    Parent.Throttle_vorhanden = 0;
    root.Hauptfenster.LastPositionThrottlePlate=this.getLocation();
    this.dispose();
} 

And here I try to set the old location again:

public Throttle(Hauptfenster parent, root.rs232.rs232Connection Conn, Integer throttlePosition) {
    super();
    Parent = parent;
    conn = Conn;
    actualThrottlePosition = throttlePosition;
    initComponents();

    jScrollBar2.setValue(root.Hauptfenster.MPR);
    this.setTitle("Throttle");

    this.setVisible(true);
    if (root.Hauptfenster.LastPositionThrottlePlate!=null) {
        this.setLocation(root.Hauptfenster.LastPositionThrottlePlate); 
    }

For a very little bit a secound, I see the Frame on its old position, but then it "jumps" in the middle of the screen...

Can anyone imagine why jFrame behavior like this? sorry for my english...

Answer 1

Set the JFrame as visible after you have correctly positioned it.

It is just a matter of inverting the order of your lastoperations:

if (root.Hauptfenster.LastPositionThrottlePlate!=null) {
    this.setLocation(root.Hauptfenster.LastPositionThrottlePlate); 
}

this.setVisible(true);

Answer 2

It's probably because you're displaying your window before moving the JFrame.

Your code says:

this.setVisible(true);
if (root.Hauptfenster.LastPositionThrottlePlate!=null) {
    this.setLocation(root.Hauptfenster.LastPositionThrottlePlate); 
}

I would suggest reversing the order:

if (root.Hauptfenster.LastPositionThrottlePlate!=null) {
    this.setLocation(root.Hauptfenster.LastPositionThrottlePlate); 
}
this.setVisible(true);

This will set it to it's "final" position before showing it.

Answer 3

Why don't you just setLocationRelativeTo(parent) instead of trying to set the location manually.

---

Side Notes:

• Use Java naming convention. variable names start with lowecase letters. I see you have Parent and parent. That's where this comes in handy

  this.parent = parent
  

  instead of

  Parent = parent
  

• It looks like you're trying to use two JFrame. Why? There other more user friendly options like a model JDialog or a CardLayout. See The Use of Multiple JFrames, Good/Bad Practice?

---

UPDATE

Though I'm against the use of multiple frames, I will still give you an answer, Only because I took my time to actually test this out. Here are the steps I took in GUI Builder, which it looks like that's what you're using.

1. I made two JFrame forms FrameOne and FrameTwo.
2. I changed the defaultCloseOperation of FrameOne to DISPOSE
3. In FrameTwo I deleted the main method because the application is already running from the FrameOne class. I kept the look and feel code though. Just cop and pasted it to the constructor.

4. I Did this, set the location relative to the first frame

   FrameOne frameOne;
   
   public FrameTwo(FrameOne frameOne) {
       initComponents();
       this.frameOne = frameOne;
       // look and feel code here
       setLocationRelativeTo(frameOne);
       setVisible(true);
   }
   

5. Added a WindowListener to the FrameOne

   public FrameOne() {
       initComponents();
   
       addWindowListener(new WindowAdapter(){
           @Override
           public void windowClosing(WindowEvent e) {
               new FrameTwo(FrameOne.this);
               FrameOne.this.dispose();
          }
       });
   }
   

It works fine.

---

FrameOne.java

UPATE with code from GU Builder

I added no components to FrameOne, just close the frame. The only things I did was what I mentioned in the steps above

import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.GroupLayout;
import javax.swing.WindowConstants;

public class FrameOne extends javax.swing.JFrame {

    public FrameOne() {
        initComponents();

        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                new FrameTwo(FrameOne.this);
                FrameOne.this.dispose();
            }
        });
    }

    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);

        GroupLayout layout = new GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(GroupLayout.Alignment.LEADING)
            .addGap(0, 400, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(GroupLayout.Alignment.LEADING)
            .addGap(0, 300, Short.MAX_VALUE)
        );

        pack();
    }// </editor-fold>                        

    public static void main(String args[]) {

        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(FrameOne.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(FrameOne.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(FrameOne.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(FrameOne.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new FrameOne().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    // End of variables declaration                   
}

FrameTwo.java

import java.awt.Font;
import javax.swing.GroupLayout;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import javax.swing.WindowConstants;


public class FrameTwo extends javax.swing.JFrame {

    private FrameOne frameOne;

    public FrameTwo(final FrameOne frameOne) {
        initComponents();
        this.frameOne = frameOne;
        setLocationRelativeTo(frameOne);
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(FrameTwo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(FrameTwo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(FrameTwo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(FrameTwo.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        setVisible(true);
    }

    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jLabel1 = new JLabel();

        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        jLabel1.setFont(new Font("Impact", 0, 36)); // NOI18N
        jLabel1.setHorizontalAlignment(SwingConstants.CENTER);
        jLabel1.setText("frame two");

        GroupLayout layout = new GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(118, 118, 118)
                .addComponent(jLabel1, GroupLayout.PREFERRED_SIZE, 161, GroupLayout.PREFERRED_SIZE)
                .addContainerGap(121, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(90, 90, 90)
                .addComponent(jLabel1, GroupLayout.PREFERRED_SIZE, 89, GroupLayout.PREFERRED_SIZE)
                .addContainerGap(121, Short.MAX_VALUE))
        );

        pack();
    }// </editor-fold>                        



        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */

        //</editor-fold>



    // Variables declaration - do not modify                     
    private JLabel jLabel1;
    // End of variables declaration                   
}