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Swing - Get to the next "page" when pressing a button [duplicate]

To put it simple, there's a simple java swing app that consists of JFrame with some components in it. One of the components is a JPanel that is meant to be replaced by another JPanel on user action.
So, what's the correct way of doing such a thing? I've tried
panel = new CustomJPanelWithComponentsOnIt();
parentFrameJPanelBelongsTo.pack();
but this won't work. What would you suggest?

Your use case, seems perfect for CardLayout.
In card layout you can add multiple panels in the same place, but then show or hide, one panel at a time.

1) Setting the first Panel:
JFrame frame=new JFrame();
frame.getContentPane().add(new JPanel());
2)Replacing the panel:
frame.getContentPane().removeAll();
frame.getContentPane().add(new JPanel());
Also notice that you must do this in the Event's Thread, to ensure this use the SwingUtilities.invokeLater or the SwingWorker

frame.setContentPane(newContents());
frame.revalidate(); // frame.pack() if you want to resize.
Remember, Java use 'copy reference by value' argument passing. So changing a variable wont change copies of the reference passed to other methods.
Also note JFrame is very confusing in the name of usability. Adding a component or setting a layout (usually) performs the operation on the content pane. Oddly enough, getting the layout really does give you the frame's layout manager.

Hope this piece of code give you an idea of changing jPanels inside a JFrame.
public class PanelTest extends JFrame {
Container contentPane;
public PanelTest() {
super("Changing JPanel inside a JFrame");
contentPane=getContentPane();
}
public void createChangePanel() {
contentPane.removeAll();
JPanel newPanel=new JPanel();
contentPane.add(newPanel);
System.out.println("new panel created");//for debugging purposes
validate();
setVisible(true);
}
}

On the user action:
// you have to do something along the lines of
myJFrame.getContentPane().removeAll()
myJFrame.getContentPane().invalidate()
myJFrame.getContentPane().add(newContentPanel)
myJFrame.getContentPane().revalidate()
Then you can resize your wndow as needed.

Game game = new Game();
getContentPane().removeAll();
setContentPane(game);
getContentPane().revalidate(); //IMPORTANT
getContentPane().repaint(); //IMPORTANT

It all depends on how its going to be used. If you will want to switch back and forth between these two panels then use a CardLayout. If you are only switching from the first to the second once and (and not going back) then I would use telcontars suggestion and just replace it. Though if the JPanel isn't the only thing in your frame I would use
remove(java.awt.Component) instead of removeAll.
If you are somewhere in between these two cases its basically a time-space tradeoff. The CardLayout will save you time but take up more memory by having to keep this whole other panel in memory at all times. But if you just replace the panel when needed and construct it on demand, you don't have to keep that meory around but it takes more time to switch.
Also you can try a JTabbedPane to use tabs instead (its even easier than CardLayout because it handles the showing/hiding automitically)

The other individuals answered the question. I want to suggest you use a JTabbedPane instead of replacing content. As a general rule, it is bad to have visual elements of your application disappear or be replaced by other content. Certainly there are exceptions to every rule, and only you and your user community can decide the best approach.

Problem: My component does not appear after I have added it to the container.
You need to invoke revalidate and repaint after adding a component before it will show up in your container.
Source: http://docs.oracle.com/javase/tutorial/uiswing/layout/problems.html

I was having exactly the same problem!! Increadible!! The solution I found was:
Adding all the components (JPanels) to the container;
Using the setVisible(false) method to all of them;
On user action, setting setVisible(true) to the panel I wanted to
show.
// Hiding all components (JPanels) added to a container (ex: another JPanel)
for (Component component : this.container.getComponents()) {
component.setVisible(false);
}
// Showing only the selected JPanel, the one user wants to see
panel.setVisible(true);
No revalidate(), no validate(), no CardLayout needed.

The layout.replace() answer only exists/works on the GroupLayout Manager.
Other LayoutManagers (CardLayout, BoxLayout etc) do NOT support this feature, but require you to first RemoveLayoutComponent( and then AddLayoutComponent( back again. :-) [Just setting the record straight]

I suggest you to add both panel at frame creation, then change the visible panel by calling setVisible(true/false) on both.
When calling setVisible, the parent will be notified and asked to repaint itself.

class Frame1 extends javax.swing.JFrame {
remove(previouspanel); //or getContentPane().removeAll();
add(newpanel); //or setContentPane(newpanel);
invalidate(); validate(); // or ((JComponent) getContentPane()).revalidate();
repaint(); //DO NOT FORGET REPAINT
}
Sometimes you can do the work without using the revalidation and sometimes without using the repaint.My advise use both.

Just call the method pack() after setting the ContentPane, (java 1.7, maybe older) like this:
JFrame frame = new JFrame();
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
....
frame.setContentPane(panel1);
frame.pack();
...
frame.setContentPane(panel2);
frame.pack();
...

I can't to get Label and Buttons components in created window

I tryed to learn about GUI and tryed to create the window with two buttons and jne Label on the screen. But I don't understand why I can't see these elements simultaneously. When I comment out lines for buttons I can see the Label element.
Here is my code:
import java.awt.*;
import javax.swing.*;
public class MyWin {
public static void main(String[] args) {
JFrame w = new JFrame("My Window");
w.setSize(1000,800);
w.setVisible(true);
JButton b = new JButton("My button");
b.setVisible(true);
b.setSize(150, 100);
b.setLocation(500, 20);
JButton b2 = new JButton("Second button");
b2.setVisible(true);
b2.setSize(150,100);
b2.setLocation(500, 600);
JLabel l = new JLabel("My label");
l.setVisible(true);
w.getContentPane().add(b);
w.getContentPane().add(b2);
w.getContentPane().add(l);
}
}

The default layout for the JFrame is BorderLayout and when you add your JLabel through single parameter add method you add it with a BorderLayour.CENTER constraint as a default, this causes to fill all the available space. So you might want to use layout manager suitable for your needs, then the components won't overlay themselves.
Visual Guide to Layour Managers

First of all, JFrame uses BorderLayout as a default layout and just adding the components (w.getContentPane().add(b)) sets them in BorderLayout.CENTER; where they occupy the whole JFrame to fill the empty space. Thus, is recommended to add components in a JPanel. So, you should create first a JPanel, add the components to the JPanel and finally add it to the JFrame.
The setSize(...); statement is not applied due to the default layout (FlowLayout) in JPanels and also is discouraged. (Because it won't work properly in different computers with different screen resolutions)
If you want to change the size of the components you should change the default layout and use instead a customLayout, borderLayout, gridLayout...
If you want to understand deeply how layouts work and all the available layouts in Java check this

older jPanel vanish when jFrame is refreshed

I am coding an intense game and have an important question. In this game, thanks to searching and finding the revalidate() method and the repaint() method I have managed to successfully remove a JPanel and place another JPanel in it's place.
However... this is where the problems begin. I am able to do this, but there are multiple (can range from 9 to 729) such JPanels that need to be changed. I am able to do this in the JFrame no problem... however the issue I am currently facing is that although one JPanel is replaced properly, when I do the next one it is also replaced properly. However, after multiple tests I found that when the JFrame is refreshed by dragging it off and back on screen or any other such change the older changed JPanels vanish.
Is there any way that I can make the newly added JPanel's permanently there rather than vanishing if and only if the JFrame is refreshed??
Here is the code:
int a = f%27;
int b = g%27;
int c = a%9;
int d = b%9;
winningletter.setFont(new Font("Times New Roman", Font.BOLD, 17));
miniwin.add(winningletter);
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).removeAll();
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).setLayout(new GridLayout(1,1));
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).add(miniwin);
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).repaint();
metametametaminiminiwincheck[f/3][g/3]=winningletter.getText();
boardChanger(f, g, 4);
WinChecker(s, f,g,3,4,metametametaminiminiwincheck,x);

You should be using CardLayout: The CardLayout class manages two or more components (usually JPanel instances) that share the same display space.
It enables you to flip between panels the pro way. Each JPanel has an ID and you can display it using it.
link:
http://docs.oracle.com/javase/tutorial/uiswing/layout/card.html
Code:
//Where instance variables are declared:
JPanel cards;
final static String BUTTONPANEL = "BUTTONPANEL";
final static String TEXTPANEL = "TEXTPANEL";
//Where the components controlled by the CardLayout are initialized:
//Create the "cards".
JPanel card1 = new JPanel();
JPanel card2 = new JPanel();
//Create the panel that contains the "cards".
cards = new JPanel(new CardLayout());
cards.add(card1, BUTTONPANEL);
cards.add(card2, TEXTPANEL);
Calling the JPanel to display:
CardLayout cl = (CardLayout)(cards.getLayout());
cl.show(cards, BUTTONPANEL);

I found that when the JFrame is refreshed by dragging it off and back
on screen or any other such change the older changed JPanels vanish
Emm... it seems naturally that UI repaint() method is being invoked authomatically after you re-size JFrame etc :)
thanks to searching and finding the revalidate() method and the
repaint() method I have managed to successfully remove a JPanel
It is quite strange you point your code strategy for the graphics2d only :S If you don't need to paint a new UI every time but keep them , as I could get it, inited in the heap not to re-init to set into your JPanel (?which is acting as a canvas)...
Actually, if you want all JPanel(s) be inited at the same time and just get them one by one by some event you can simply use some kind of storage as a Map or List etc, add them all (invisible) to your 'canvas' preferrably FlowLayout manager and make a needed one visible/invisible by an event for example...
Still the major task you trying to achieve is not pretty clear because you do accent Graphics2D so maybe you trying to achieve some another effect ? :S
P.S.
Anyway, it would be better you to show the problem code snippet because your current question contains too less information as for now...
EDIT
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).removeAll();
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).setLayout(new GridLayout(1,1));
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).add(miniwin);
((JPanel)((JPanel)newDossier.Board.metametametaboard[f/27][g/27].getComponent((a/9)*3+b/9)).getComponent((c/3)*3+d/3)).repaint();
Ok... so that is how you add component to your canvas... As I can see, the array in Board is static object... I may suggest, you have more than one canvas object(s)? If yes, it is naturally the miniwin(s) vanish because static array cannot have shared access by two invokers at a time; so I may recommend not to use static field in your case... Please read The Java Language Specification for more detailed information
If you have additional question details please comment
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only JLabel not showing up

I am writting a simple application which has a button that opens a new window then display a simple GUI/Text to acccept inputs from a user. but for some reason, I can get JLabel to be displayed on the new window. The application has following structure:
+mainFrame - JFrame
+newFrame - JFrame
-+newPanel - JPanel
----title - JLabel
----submitButton -JButton
...
Buttons and textfields all display fine, but Jlabels won't show up at all. I have tried using different layouts and all but I still can't get it shown. JLabels inside mainFrame tree, works fine.. so it seems like the problem is due to newFrame declaration or something, but then button should not be displayed either. Well, I am kindda lost and can someone suggest me what I should check?
Thanks : )

Make sure you do frame.pack() before you make it visible.
It can also help to set borders on different components (in different colours) for debugging just to see which components are/aren't turning out with size 0, in order to narrow down your problem. Logging, or breakpointing the component's setSize method, can help too.
Apart from that, maybe post some sample code? At the moment, you're question is fairly vague to answer.

Firstly, do you know about JDialog, and JOptionPane - these classes are often a better way of showing another popup window. It is quite rare to use 2 JFrames, (though sometimes a sensible thing to do).
Secondly have you done pack() and setVisible(true)?
The code below works fine for me. Either this breaks for you and it is something about your Java implementation, or you must be doing something different, in which case can you tell us what it is:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class JLabelShower {
public static void main(String [] args) {
JFrame mainFrame = new JFrame("main frame");
JButton popup = new JButton("start new frame");
mainFrame.getContentPane().add(popup);
mainFrame.pack();
mainFrame.setVisible(true);
popup.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JFrame newFrame = new JFrame("new frame");
JPanel newPanel = new JPanel();
JLabel title = new JLabel("title");
newPanel.add(title);
newFrame.setContentPane(newPanel);
newFrame.pack();
newFrame.setVisible(true);
}
});
}
}

In case you are using the JLabel as a placeholder, i.e. initialize it with an empty string and set the text later:
Since the JLabel's size gets calculated when the panel gets layed out (i.e. early on) and is based on the contained text, you'll probably end up with a label thinking it has a preferred size of (0, 0).
In this case you should tell the label what size it should ask for by calling setPreferredSize with an appropriate value.
And another cause might be the layoutmanager you are using in the surrounding panel. Maybe you are adding the label and the button in the same place, e.g. BorderLayout.CENTER. That would explain why only one of the two gets displayed.

Set the opacity of the JLabel object to true using title.setOpaque(true) . It will paint every pixel within bound of the JLabel object. This solved my problem of same type.

Adding JTextField to a JPanel and showing them

I'm building a little app using Java and Swing in NetBeans. Using NetBeans design window, I created a JFrame with a JPanel inside.
Now I want to dynamically add some jTextFields to the JPanel.
I wrote something like that:
Vector textFieldsVector = new Vector();
JTextField tf;
int i = 0;
while (i < 3) {
tf = new JTextField();
textFieldVector.add(tf);
myPanel.add(tf); //myPanel is the JPanel where I want to put the JTextFields
i++;
}
myPanel.validate();
myPanel.repaint();
But nothing happens: when I run the app, the JFrame shows with the JPanel inside, but the JTextFields don't.
I'm a total newbie in writing graphical Java apps, so I'm surely missing something very simple, but I can't see what.

In the Netbeans GUI, set the layout manager to something like GridLayout or FlowLayout (just for testing). You can do this by going to the GUI editor, clicking on your panel, and then right-clicking and selecting a layout.
Once you've changed to a different layout, go to the properties and alter the layout properties. For the GridLayout, you want to make sure you have 3 grid cells.
Instead of myPanel.validate(), try myPanel.revalidate().
The more canonical way to do this is to create a custom JPanel (without using the GUI editor) that sets its own layout manager, populates itself with components, etc. Then, in the Netbeans GUI editor, drag-and-drop that custom JPanel into the gui editor. Matisse is certainly capable of handling the runtime-modification of Swing components, but that's not the normal way to use it.

It's been a while since I've done some Swing but I think you'll need to recall pack() to tell the frame to relayout its components
EDIT: Yep, I knew it had been too long since I did Swing. I've knocked up the following code which works as expected though and adds the textfields...
JFrame frame = new JFrame("My Frame");
frame.setSize(640, 480);
JPanel panel = new JPanel();
panel.add(new JLabel("Hello"));
frame.add(panel);
frame.setLayout(new GridLayout());
frame.pack();
frame.setVisible(true);
Vector textFieldVector = new Vector();
JTextField tf;
int i = 0;
while (i < 3) {
tf = new JTextField();
textFieldVector.add(tf);
panel.add(tf); //myPanel is the JPanel where I want to put the JTextFields
i++;
}
panel.validate();
panel.repaint();

Your while loop is wrong. i never gets incremented so your window creation is in an endless loop and your CPU consumption should be at 100% until you abort the program. Also, the GUI should be completely non-responsive when you run your program.

The usual way to use GroupLayout is to add a component to a Group. GroupLayout keeps a reference to the Container it is responsible for (which makes sense). You shouldn't be adding the component to the panel without constraints.

Don't use GroupLayout with new (dynamically added) component. It won't show up.

Just use the .setVisible() method of JTextField:
JTextField tf = new JTextField() ;
tf.setVisible(true) ;
panel.add(tf) ;