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Extending variable scope from one frame to another frame

I have two JFrame based windows: SeatLayout and BillSummary. I need to get the seatnumber from the SeatLayout frame and display it in BillSummary but the variable scope is limited to the first frame.
How can I do this?

Using multiple JFrame is a bad practice and it should be avoided.
Reason being, it will add more problems in the future and it will be nightmare to maintain.
To answer your question , how to pass variable from your parent(JFrame) to a child(JDialog) .This can achive by using JDialog.
I am going to run through an example.
lets say, your BillSummary.java is ....
//BillSummary Class
public class billSummary {
JFrame frame;
billSummary(JFrame frame) {
this.frame = frame;
}
public void launchbillSummary(int seatNumber) {
// Create a dialog that suits your ui , you can use JPanel as your layout container
JDialog dialog = new JDialog(frame, "Bill Summary", true);
dialog.setLayout(new BorderLayout());
dialog.setSize(100, 100);
dialog.add(new JLabel(Integer.toString(seatNumber)), BorderLayout.CENTER);
dialog.setVisible(true);
}
}
Your seatLayout.java
public class seatLayout {
seatLayout(){
//Lets say you have seleted seat number 10
int defaultSeatNumber = 10;
//Lets say you have a button and when it is clicked , you pass the data to billsummary page
JButton enter = new JButton("Enter");
//Your seatLayout GUI
JFrame frame = new JFrame("seat layout");
frame.setSize(300,300);
frame.add(enter);
enter.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
//Do your passing of data/ price of calculation here
//You pass the data that to your custom dialog -> Bill summary
new billSummary(frame).launchbillSummary(defaultSeatNumber);
}
});
frame.setVisible(true);
}
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new seatLayout();
}
});
}
}
I hope this help and answers your question. Good luck :)

Displaying an image in a JFrame

I am currently learning Java, and I am stuck with something at the moment.
I was looking for a way to add an image to my JFrame.
I found this on the internet:
ImageIcon image = new ImageIcon("path & name & extension");
JLabel imageLabel = new JLabel(image);
And after implementing it to my own code, it looks like this (this is only the relevant part):
class Game1 extends JFrame
{
public static Display f = new Display();
public Game1()
{
Game1.f.setSize(1000, 750);
Game1.f.setResizable(false);
Game1.f.setVisible(true);
Game1.f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Game1.f.setTitle("Online First Person Shooter");
ImageIcon image = new ImageIcon("C:\\Users\\Meneer\\Pictures\\image.png");
JLabel imageLabel = new JLabel(image);
add(imageLabel);
}
}
class Display extends JFrame
{
}
When running this code, it doesn't give me any errors, but it also doesn't show the picture. I saw some questions and people having the same problem, but their code was completely different from mine, they used other ways to display the image.

You don't need to use another JFrame instance inside the Game JFrame:
Calling setVisible(flag) from the constructor is not preferable. Rather initialize your JFrame from outside and put your setVisible(true) inside event dispatch thread to maintain Swing's GUI rendering rules using SwingUtilities.invokeLater(Runnable)
Do not give size hint by setSize(Dimension) of the JFrame. Rather use proper layout with your component, call pack() after adding all of your relevant component to the JFrame.
Try using JScrollPane with JLabel for a better user experience with image larger than the label's size can be.
All of the above description is made in the following example:
class Game1 extends JFrame
{
public Game1()
{
// setSize(1000, 750); <---- do not do it
// setResizable(false); <----- do not do it either, unless any good reason
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("Online First Person Shooter");
ImageIcon image = new ImageIcon("C:\\Users\\Meneer\\Pictures\\image.png");
JLabel label = new JLabel(image);
JScrollPane scrollPane = new JScrollPane(label);
scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
add(scrollPane, BorderLayout.CENTER);
pack();
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Game1().setVisible(true);
}
});
}
}

do this after creating Jlabel
imageLabel.setBounds(10, 10, 400, 400);
imageLabel.setVisible(true);
also set the layout to JFrame
Game.f.setLayout(new FlowLayout);

You are adding the label to the wrong JFrame. Also, move the setVisible() to the end.
import javax.swing.*;
class Game1 extends JFrame
{
public static Display f = new Display();
public Game1()
{
// ....
Game1.f.add(imageLabel);
Game1.f.setVisible(true);
}
}

Also try to use image from resources, and not from hardcoded path from your PC
You can look in here, where sombody asked similar question about images in Jframe:
How to add an ImageIcon to a JFrame?

Your problem in next you add your JLabel to Game1 but you display another Frame(Display f). Change add(imageLabel); to Game1.f.add(imageLabel);.
Recommendations:
1)according to your problem: Game1 extends JFrame seems that Display is also a frame, use only one frame to display content.
2) use pack() method instead of setSize(1000, 750);
3)call setVisible(true); at the end of construction.
4)use LayoutManager to layout components.

How can I minimize/iconify a JWindow in Java?

My app has a JWindow that needs to be minimized when the custom minimizer button clicked.
Please reply if anyone knows how to minimize a JWindow. I have searched a lot but couldn't find any suitable method to minimize.
I know how to minimize a JFrame. So please don't bother answering regarding JFrame.
Thanks.

I know you don't want to hear this, but the terrible truth is that there is no big difference between undecorated jframes (with setstate methods) and jwindows... :)
JFrame f = new JFrame("Frame");
f.setUndecorated(true);

Due to the fact that a JWindow is not decorated with any control icons, no setState method is provided. One workaround is to allow your custom minimizer button to set the window visible as required:
public class JWindowTest extends JFrame {
JWindow window = new JWindow();
JButton maxMinButton = new JButton("Minimize Window");
public JWindowTest() {
setSize(300, 200);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
maxMinButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (window.isVisible()) {
maxMinButton.setText("Restore Window");
} else {
maxMinButton.setText("Minimize Window");
}
window.setVisible(!window.isVisible());
}
});
add(maxMinButton);
window.setBounds(30, 30, 300, 220);
window.setLocationRelativeTo(this);
window.add(new JLabel("Test JWindow", JLabel.CENTER));
window.setVisible(true);
}
public static void main(String[] args) {
new JWindowTest().setVisible(true);
}
}

JFrame image display at frame resize

I have this JFrame containing a children of JPanel wherein it displays the image which is declared in this manner.
BufferedImage image = ImageIO.read(filename);
The program displays the image properly. But the only thing is, it requires to resize the frame to display the image.
Is there a possible way to display the image once the frame appears?

You should override paintComponent(Graphics g) and draw the image therein. In this case, you should do this for the JPanel component (I think? If not, do this for the JComponent(s) you're referring to). Also, since Swing is not thread-safe, ensure these modifications are performed in the EDT.
EXAMPLE
public class Demo{
private static BufferedImage bi;
public static void main(String[] args){
try{
loadImage();
SwingUtilities.invokeLater(new Runnable(){
#Override
public void run(){
createAndShowGUI();
}
});
}
catch (IOException e){
// handle exception
}
}
private static void loadImage() throws IOException{
bi = ImageIO.read(new File("src/resource/braveheart.PNG"));
}
private static void createAndShowGUI(){
final JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final JPanel panel = new JPanel(){
#Override
protected void paintComponent(Graphics g){
Graphics g2 = g.create();
g2.drawImage(bi, 0, 0, getWidth(), getHeight(), null);
g2.dispose();
}
#Override
public Dimension getPreferredSize(){
return new Dimension(bi.getWidth(), bi.getHeight());
}
};
frame.add(panel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
OUTPUT
It's important to keep in mind that this example ignores rendering hints, so when you maximize the JFrame, the image quality will be very poor. :)
EDIT
When answering this question, I assumed you had a basic understanding of Swing. I suppose I assumed too much. It is important to mention that all components should be added to the top-level container before it's been realized (i.e. made visible). This will ensure that everything is rendered without having to resize your frame. As others have suggested, you could have simply used a JLabel to render the image, and then added it to your JPanel. Instead, I promoted custom painting, which is perfectly acceptable, and to me, cleaner.

for dispaly Image or ImageIcon is better look for JLabel (basic stuff)

Opening a new jframe with the same properties as the closed one

How can I have the newly open jframe have the same properties like Size and position on screen. Thanks

If you are only interested in size and position JFrame.getBounds returns these properties:
newFrame.setBounds(oldFrame.getBounds());
public static void main(String args[]) throws Exception {
final JFrame oldFrame = new JFrame("Test");
oldFrame.addWindowListener(new WindowAdapter() {
#Override
public void windowClosing(WindowEvent e) {
JFrame newFrame = new JFrame("Test");
newFrame.setBounds(oldFrame.getBounds());
newFrame.setVisible(true);
}
});
oldFrame.setSize(400, 300);
oldFrame.setVisible(true);
}

#Sam that not good idea to create new TopLevelContainer on fly, better would be reuse exist JFrame and just replace/switch its contents JPanel and if you need/want to display more TopLevelContainers then others would by JDialog(s)
please check how to LayoutManagers works (with examples there) and tons of example about Swing on Java2s.com