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JFrame appears blank after swapping JFrames twice (using Intellij GUI designer)

I'm relatively new to Java Swing in general and decided to use Intellij's GUI Designer. For those not familiar with it, Intellij creates 2 files for each GUI "screen". One is the "design" in the form of a .form file where you drag and drop UI components, and one is the "controller".
Anyway, I'm doing a 5-step questionnaire implemented on Java Swing. The first part asks the user what is their favourite fruit, and when a choice button is clicked, the choice is saved and the next JFrame appears with the next question and so on. JFrame1 transitioning to JFrame2 worked fine, and all UI components were shown. However, when I tried to transition from JFrame2 to JFrame3, JFrame3 showed up blank instead.
I've tried to call .pack() before setVisible(true), and then calling .toFront() after that, but that didn't help.
Below shows a section of my code. JFrame1, 2, and 3 all use the same exact code in its constructors and calling of the next JFrame. JFrame1 only differs by a single line which will be stated later in the code.
JFrame1.java
public class Frame1 extends JFrame {
private JPanel mainPanel;
private JLabel narrationLabel;
private JButton option1_btn;
private JButton option2_btn;
private JButton option3_btn;
public Frame1()
{
setTitle("Questionnaire");
setSize(1000, 1000);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Frame2 nextScreen = new Frame2 (); //declare the next screen to show
add(mainPanel); //this is only for the first starting JFrame
//JFrame2 and JFrame3 do not have this
//repeat this for buttons option2_btn and option3_btn
option1_btn.addActionListener(new ActionListener()
{
#Override
public void actionPerformed(ActionEvent e)
{
//swap screens to the next main filler selection screen
mainPanel.setVisible(false);
nextScreen.pack();
add(nextScreen.getPanel());
nextScreen.getPanel().setVisible(true);
}
});
}
public JPanel getPanel()
{
return mainPanel;
}
}
Main.java
public class Main
{
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame1 frame1 = new JFrame1(); //create start screen GUI
frame1.setVisible(true); //display GUI
}
});
}
}
My hunch tells me it might a concurrency issue, but I'm not sure if I am right, or where is the issue and how to resolve it. If a .form file is needed, I would gladly upload the code for it. Any help appreciated.

Passing an object from one JFrame to another [duplicate]

I have two Jframes where frame1 has some text fields and when a button on frame1 is clicked, I open another JFrame which contains a search box and a JTable containing search results.
When I click on a result row on JTable, I want that particular values to be reflected in the frame1 text fields.
I tried passing the JFrame1's object as a parameter but I have no clear idea on how to achieve this.
Any help would be highly appreciated.
Thanks

First of all, your program design seems a bit off, as if you are using a JFrame for one of your windows where you should in fact be using a JDialog since it sounds as if one window should be dependent upon the other.
But regardless, you pass references of GUI objects the same as you would standard non-GUI Java code. If one window opens the other (the second often being the dialog), then the first window usually already holds a reference to the second window and can call methods off of it. The key often is when to have the first window call the second's methods to get its state. If the second is a modal dialog, then the when is easy -- immediately after the dialog returns which will be in the code immediately after you set the second dialog visible. If it is not a modal dialog, then you probably want to use a listener of some sort to know when to extract the information.
Having said this, the details will all depend on your program structure, and you'll need to tell us more about this if you want more specific help.
For a simple example that has one window open another, allows the user to enter text into the dialog windows JTextField, and then places the text in the first window's JTextField, please have a look at this:
import java.awt.Window;
import java.awt.Dialog.ModalityType;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class WindowCommunication {
private static void createAndShowUI() {
JFrame frame = new JFrame("WindowCommunication");
frame.getContentPane().add(new MyFramePanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
// let's be sure to start Swing on the Swing event thread
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
class MyFramePanel extends JPanel {
private JTextField field = new JTextField(10);
private JButton openDialogeBtn = new JButton("Open Dialog");
// here my main gui has a reference to the JDialog and to the
// MyDialogPanel which is displayed in the JDialog
private MyDialogPanel dialogPanel = new MyDialogPanel();
private JDialog dialog;
public MyFramePanel() {
openDialogeBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
openTableAction();
}
});
field.setEditable(false);
field.setFocusable(false);
add(field);
add(openDialogeBtn);
}
private void openTableAction() {
// lazy creation of the JDialog
if (dialog == null) {
Window win = SwingUtilities.getWindowAncestor(this);
if (win != null) {
dialog = new JDialog(win, "My Dialog",
ModalityType.APPLICATION_MODAL);
dialog.getContentPane().add(dialogPanel);
dialog.pack();
dialog.setLocationRelativeTo(null);
}
}
dialog.setVisible(true); // here the modal dialog takes over
// this line starts *after* the modal dialog has been disposed
// **** here's the key where I get the String from JTextField in the GUI held
// by the JDialog and put it into this GUI's JTextField.
field.setText(dialogPanel.getFieldText());
}
}
class MyDialogPanel extends JPanel {
private JTextField field = new JTextField(10);
private JButton okButton = new JButton("OK");
public MyDialogPanel() {
okButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
okButtonAction();
}
});
add(field);
add(okButton);
}
// to allow outside classes to get the text held by the JTextField
public String getFieldText() {
return field.getText();
}
// This button's action is simply to dispose of the JDialog.
private void okButtonAction() {
// win is here the JDialog that holds this JPanel, but it could be a JFrame or
// any other top-level container that is holding this JPanel
Window win = SwingUtilities.getWindowAncestor(this);
if (win != null) {
win.dispose();
}
}
}
You'd do a very similar technique to get information out of a JTable.
And again, if this information doesn't help you, then please tell us more about your program including showing us some of your code. The best code to show is a small compilable example, an SSCCE similar to what I've posted above.

Disable JFrame minimize button

I am developing a tool for my laptop. I want to disable minimize button in the JFrame. I have already disabled maximize and close button.
Here is the code to disable maximize and close button:
JFrame frame = new JFrame();
frame.setResizable(false); //Disable the Resize Button
// Disable the Close button
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
Please, tell me how to disable minimize button.

Generally, you can't, what you can do is use a JDialog instead of JFrame

As #MadProgrammer said (+1 to him), this is definitely not a good idea you'd rather want to
use a JDialog and call setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE); to make sure it cannot be closed.
You could also use a JWindow (+1 to #M. M.) or call setUndecorated(true); on your JFrame instance.
Alternatively you may want to add your own WindowAdapater to make the JFrame un-minimizable etc by overriding windowIconified(..) and calling setState(JFrame.NORMAL); from within the method:
//necessary imports
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
public class Test {
/**
* Default constructor for Test.class
*/
public Test() {
initComponents();
}
public static void main(String[] args) {
/**
* Create GUI and components on Event-Dispatch-Thread
*/
javax.swing.SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
Test test = new Test();
}
});
}
private final JFrame frame = new JFrame();
/**
* Initialize GUI and components (including ActionListeners etc)
*/
private void initComponents() {
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.setResizable(false);
frame.addWindowListener(getWindowAdapter());
//pack frame (size JFrame to match preferred sizes of added components and set visible
frame.pack();
frame.setVisible(true);
}
private WindowAdapter getWindowAdapter() {
return new WindowAdapter() {
#Override
public void windowClosing(WindowEvent we) {//overrode to show message
super.windowClosing(we);
JOptionPane.showMessageDialog(frame, "Cant Exit");
}
#Override
public void windowIconified(WindowEvent we) {
frame.setState(JFrame.NORMAL);
JOptionPane.showMessageDialog(frame, "Cant Minimize");
}
};
}
}

If you don't want to allow any user action use JWindow.

You may try to change your JFrame type to UTILITY. Then you will not see both minimize btn and maximize btn in your program.

I would recommend you to use jframe.setUndecorated(true) as you are not using any of the window events and do not want the application to be resized. Use the MotionPanel that I've made, if you would like to move the panel.

One JFrame opening another

I have a JFrame and JPanel full of Jsomethings with an actionlistener. When the user clicks an object I want to open another JFrame. Here is what I did:
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source == rejectionbutton){
RejectApp ra = new RejectApp();
ra.main(null);
}
}
(RejectApp calls a new JFrame.) So another JFrame opens on the screen with more options. It works OK (so far), but I want to know is this standard? I mean calling the main method like this?
Another question is, without using a cardlayout (which I don't want to use), is the best way to handle multiple panels, by doing this sort of thing?

I would change a few things. First off, usually an application has one JFrame and then if it needs to show another window does so as a modal or non-modal dialog such as can be obtained with a JDialog or JOptionPane. Having said that, it's even more common to have one JFrame and swap "views" in the JFrame -- swap contentPanes or other large panels via a CardLayout as this would mimic the behavior of many gui programs we all currently use.
Personally, I also try to gear my GUI creation towards creating a JPanel or JComponent rather than towards creating a top-level window. This way if I want to display the GUI as a stand alone app, a dialog, or an applet I can pop it into the contentPane of a JFrame or JDialog or JApplet respectively, or if as an inner panel of a more complex GUI, then insert it there, or in an application with a swapping view, then as a card in a CardLayout as noted above. The bottom line is I feel that this structure gives you the developer a lot more options in how you can use this GUI.
Also, I would avoid calling another class's main as you're doing (assuming this is the public static void main method) as you lose all benefits of OOPs. You also seem to be trying to call a static method in a non-static way (assuming I understand your program structure correctly).
For your second question, it begs a question of my own: why do you not want to use CardLayout?
edit: an example of what I meant is as follows:
import java.awt.Dimension;
import java.awt.Window;
import java.awt.Dialog.ModalityType;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class SwingEg {
private static void createAndShowUI() {
JFrame frame = new JFrame("Main JFrame");
frame.getContentPane().add(new MainGUI().getMainPanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
class MainGUI {
private static final Dimension MAIN_PANEL_SIZE = new Dimension(450, 300);
private JPanel mainPanel = new JPanel();
private JDialog modalDialog;
private JDialog nonModalDialog;
public MainGUI() {
JButton openModalDialogBtn = new JButton("Open Modal Dialog Window");
openModalDialogBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
openModalDialogBtnActionPerformed(e);
}
});
JButton openNonModalDialogBtn = new JButton("Open Non-Modal Dialog Window");
openNonModalDialogBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
openNonModalDialogBtnActionPerformed(e);
}
});
mainPanel.setPreferredSize(MAIN_PANEL_SIZE);
mainPanel.add(openModalDialogBtn);
mainPanel.add(openNonModalDialogBtn);
}
private void openModalDialogBtnActionPerformed(ActionEvent e) {
if (modalDialog == null) {
Window topWindow = SwingUtilities.getWindowAncestor(mainPanel);
modalDialog = new JDialog(topWindow, "Modal Dialog", ModalityType.APPLICATION_MODAL);
modalDialog.getContentPane().add(new DialogPanel().getMainPanel());
modalDialog.pack();
modalDialog.setLocationRelativeTo(topWindow);
modalDialog.setVisible(true);
} else {
modalDialog.setVisible(true);
}
}
private void openNonModalDialogBtnActionPerformed(ActionEvent e) {
if (nonModalDialog == null) {
Window topWindow = SwingUtilities.getWindowAncestor(mainPanel);
nonModalDialog = new JDialog(topWindow, "Non-Modal Dialog", ModalityType.MODELESS);
nonModalDialog.getContentPane().add(new DialogPanel().getMainPanel());
nonModalDialog.pack();
nonModalDialog.setLocationRelativeTo(topWindow);
nonModalDialog.setVisible(true);
} else {
nonModalDialog.setVisible(true);
}
}
public JPanel getMainPanel() {
return mainPanel;
}
}
class DialogPanel {
private static final Dimension DIALOG_SIZE = new Dimension(300, 200);
private JPanel dialogPanel = new JPanel();
public DialogPanel() {
dialogPanel.add(new JLabel("Hello from a dialog", SwingConstants.CENTER));
dialogPanel.setPreferredSize(DIALOG_SIZE);
}
public JPanel getMainPanel() {
return dialogPanel;
}
}

I would rather make a new instance of JFrame or a subclass, or call a new method who makes a new JFrame:
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source == rejectionbutton){
JFrame frame = new JFrame("New Frame");
//or
makeNewFrame();
}
}
Another simple Layout-Manager is the BorderLayout, it´s the default Layout-Manager of the JFrame class.

new YourJFrameNameHere().setVisible(true);
Replace YourJFrameNameHere with the JFrame name.
Simple, no?

Text in Label not displaying correctly with setText method

I'm trying to set the text in a label dynamically by calling the setText method whenever a button is clicked. Here is my code:
import java.awt.*;
import java.awt.event.*;
class Date {
public static void main(String[] args) {
new MainWindow();
}
}
class MainWindow {
static Label month = new Label();
static Label day = new Label();
static Button submit = new Button("Submit");
MainWindow() {
Frame myFrame = new Frame("Date Window");
myFrame.setLayout(new FlowLayout());
myFrame.add(month);
myFrame.add(day);
myFrame.add(submit);
submit.addActionListener(new ButtonListener());
myFrame.addWindowListener(new WindowListener());
myFrame.setSize(200, 200);
myFrame.setVisible(true);
}
}
class WindowListener extends WindowAdapter {
#Override
public void windowClosing(WindowEvent e) {
System.exit(0);
}
}
class ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
if (event.getSource() == MainWindow.submit) {
MainWindow.month.setText("12");
MainWindow.day.setText("31");
}
}
}
When I initialize the two Label objects without any arguments, the strings "12" and "31" that are passed to the setText method aren't visible on the screen when the submit button is clicked until I click on the window and drag to resize it. I've noticed this on a Mac only. On a PC, the strings are are visible but obscured until I resize the window. However, if I initialize the labels like this:
static Label month = new Label("0");
static Label day = new Label("0");
On the Mac, the strings appear as intended, however, they're obscured until the window is resized. What am I missing?

Calling validate() on the Frame as mentioned here solved the problem.

Try repainting the frame or/and set enough space(setPreferredSize, setMininumSize)

Well, most of your posting are over a year old so I'll give you the benefit of the doubt. I never use AWT so I don't know what the problem is, but I'll suggest:
1) Name you classes properly. "Date" is already a class in the JDK. Choose a better name.
2) Try using Swing components instead of AWT.
3) Get rid of static variables from your class.
4) Get rid of the WindowListener to close the frame.
The code example you posted here is 10-15 years old. Try something newer. Start with the Swing tutorial for more recent examples.