Okay currently I am trying to make a multi-window program.
And from seeing other forums, it seems for you to do that in Java JFrame you must update its content pane by adding the new JComponent(new window/layout/idk), set the current window visibility to false, set the new one visibility to true and validate &/ repaint content pane:
contentPane.add(newWindowPanel);
currentWindowPanel.setVisible(false);
newWindowPanel.setVisible(true);
contentPane.validate();
contentPane.repaint();
now, what I am trying to do and partially have done is created a class that extends JPanel, and this class stands to be the top of an hierarchy for many other JPanel classes that I am going to create.
Within that class I have this method :
public void updateContentPane(Container contentPane, JPanel currentPanel, JPanel nextPanel){
contentPane.add(nextPanel);
currentPanel.setVisible(false);
nextPanel.setVisible(true);
contentPane.validate();
contentPane.repaint();
}
When I call this method within one of the child classes, it doesn't work.
updateContentPane(WindowMain.contentPane, this, mainMenuClass);
Each of the child class inherits the JPanel characteristic.
"WindowMain" is a class that extends JFrame, and "contentPane" is a static container variable that holds the frame contentPane.
"this" represents the current class (inherits JPane), but "this" don't actually work new Object() works.
"mainMenuClass" also inherits JPanel and has already been instantiated in this class.
My goal is to simply jump from one scene to the other by calling that method. But it goes through the code (debug) but nothing happens. But, if I take the code within the method and place it inside a button listener it works fine.
(Sorry for all this writing, it will probably bring some confusion at that, but I need to figure this out nonetheless, and I will set condition for when the contentPane already contains a class, so no need to mention it)
You could just update the whole frame by doing
frame.revalidate();
frame.repaint();
Related
I've searched and could not find the answer I need to do the following: I have two java files: one JFrame, one JPanel. I configured a button in the JFrame to open up the JPanel from within the main frame with a new size of 800,800. Now, I want to close the JPanel and go back to the original JFrame (the one that originally was at size 500,500 with an image). It seems simply straightforward, but I've created an instance of the main frame from within the JPanel and set the jPanel to (this.setVisible(false)). I created a new jFrame object and set its visibility to true. What happens is, a new instance of the JFrame appears alright, but the JFrame at 800,800 with no image still appears as well. I've tried several configurations of getContentPane(), setContentPane() and even tried passing a JFrame parameter to the constructor of the JPanel. I'm not sure where I am going wrong with this, but any help would be much appreciated. All I want is the original JFrame with the original size and image displayed. Thank you in advance.
private void jButton_closeActionPerformed(java.awt.event.ActionEvent evt) {
this.setVisible(false);
mainMenuFrame = new MainMenuFrame();
mainMenuFrame.setVisible(true);
invalidate(); validate();
repaint();
}
you could open and close the jpanel from within your JFrame. the button would be also added to the jframe instead of the jpanel. for easier accessing use the jpanel as member variable
I realize it's pointless to include a button that would do the exact same thing as the 'x' in the window, but I've already worked out the placement of my buttons on my GUI and found having the exit button made things much easier if nothing but a placeholder. And I like the practice.
Ok anyways moving on.
I have a parent JFrame (main class actually) that I'd like to keep running open the entire time the program is being run. This isn't my issue. My problem is when opening a child JFrame. I instantiate it in the main class (it's adding a panel component I created) and I just can't figure out how close said JFrame from within the Panel. Is there an easy way of doing so? I already have the WindowConstant set to Dispose on Close.
What I've done so far is created a method getExit() which returns a boolean value of true. I then have in the main class where the JFrame was instantiated an if/else if statement telling it to set the JFrame visible if exit is False, and dispose of it if true. Doesn't do anything. I'm guessing that's because either it's not bothering to check at all or I coded it poorly.
Any advice?
EDIT: Clarifying what my code is so far without posting it (600 lines of crap to get through). I have my main class Driver(). It's the fairly straight forward main JFrame 'form'.
Said class has several buttons to open up a new JFrame that performs a simple function. We'll name one of those classes (only have 3 total for the Secondary JFrames) Panel(int type) It extends JPanel.
I have a constructor set up depending that takes the int type and hides certain components in my Panel (tried to maximize the panel by combining similar functions). I have a button on the panel that is an exit button. But because the class itself is not a JFrame and does not instantiate itself, I can't dispose of it there. I have to find a way to do so in the main class.
That is my issue.
See Closing an Application. You can use the ExitAction for your JButton and it will be just like clicking the close button of the frame.
I have two classes, one AnalogClock class and one MainInterface class.
I've created a timeChanged method in the AnalogClock class and it gets called whenever the time has changed. My AnalogClock is basically a JPanel with a drawing. In MainInterface I setup a JFrame and add an Object of my AnalogClock.
Is it possible to change the Title of my Window whenever 'timeChanged' is called? I tried to use getParent() or getRootParent() but they don't recognise setTitle().
Use getWindowAncestor method from SwingUtilities.
//This gives you the first Window Object that contains the panel component
Window window = SwingUtilities.getWindowAncestor(panel);
//Cast it to JFrame
JFrame frame = (JFrame) window;
//Now, change the title
frame.setTitle("New Title");
The simplest way would be to pass a reference of the JFrame to the JPanel and invoking setTitle(). Using getParent(), you will have identify the proper type of the returned Container and then once you've found your JFrame reference, cast to it and call setTitle.
I usually do it according to the first suggestion.
It sounds like timeChanged should be in your MainInterface class because timeChanged needs to reference both the AnalogClock and the JFrame. The reason is that your AnalogClock probably should not be coupled to your JFrame.
I have a JFrame inside of which is a jpanel that im using as the content pane.
So basically im using the jpanel to load content into on click. New content is returned as a Jpanel also so its ends up being jpanel -> inside jpanel -> inside Jframe. When i need to load in new content i clear the panel, load the new content and validate() the jframe & jpanel and the new content displays.
My problem is that when the new content displays its clear that the validate method is working because i can see the new interface but i can also see the old interface as if its become the background; i can resize the window and it just disappears and looks as it should.
Is this just the way validate works or can i fix it?
Edit: this worked. The problem was i wasn't calling repaint manually.
public BaseWindow setContent(JComponent comp){
contentPane.add(comp);
contentPane.revalidate();
contentPane.repaint();
return this;
}
Generally the code for adding/removing one or two components from a panel is:
panel.remove(..);
panel.add(...);
panel.revalidate();
panel.repaint(); // sometimes needed
However, if you are replacing all the components on the panel, then the better approach is to use a Card Layout.
You have already stated the revaliate() followed by repaint() doesn't work so the only suggestion I have is to post your SSCCE that demonstrates the problem.
Don't use validate. Use revalidate() instead.
Revalidate first calls invalidate() followed by a validate().
In Swing, you would rarely use validate().
Note: I also feel that maybe the old panel is not cleared/removed.Check again!
Validate() is for causing components to re arrange themselves according to the layoutmanager that you have installed. This is not really what you should be using.
I can't see your code, so I'm not sure exactly what you are doing. I could speculate that calling repaint() on your "inner panel" will solve the problem you are having...but really, if you are doing things properly, you shouldn't need to call repaint() or validate().
Make two JPanels, one with content A (e.g. your buttons), and one with content B (e.g. your "static" field). Use the "add()" and "remove()" methods on the parent container (the JFrame's content pane?) to swap these two JPanels with each other whenever you want to switch the content that is displayed in that part of the JFrame.
Then you shouldn't need to do anything else; it should just work.
I don't know if validate() makes any promise about fully repainting the container. You might have to call repaint() yourself to make it behave as you want to.
Here's another possible solution:
Put both JPanels in at the same time, side by side, and then make sure only one of them is ever visible at any one time:
JPanel p = new JPanel(new BorderLayout());
p.add( panelA, BorderLayout.EAST );
p.add( panelB, BroderLayout.WEST );
panelA.setVisible(true);
panelB.setVisible(false);
Then when the user clicks the button to switch panels:
panelA.setVisible(false);
panelB.setVisible(true);
The setVisible() method and BorderLayout should take care of validating, layout, and calls to repaint() for you.
I ended up fixing my issue (display not shown, buttons would stay clicked/weren't unclicking) by changing which panels were added/removed.
Problem:
frame.removeAll();
frame.add(getNewPanelDisplay());
frame.revalidate();
frame.repaint();
Solution:
//initializer()
mainPanel = new JPanel();
frame.add(mainPanel());
// ...
//update()
mainPanel.remove(0);
mainPanel.add(getTablePanel(), 0);
frame.revalidate();
frame.repaint();
I have a class that extends javax.swing.JPanel, it contains a single JButton. I've created the class in NetBeans designer. As such, I have a initComponents() function thats called from the class constructor.
What I want to do is when/if a function is called, I want to add a second button, and change the layout of the two buttons. Doing simply:
public void addSecond() {
javax.swing.JButton secondButton = new javax.swing.JButton();
add(secondButton , java.awt.BorderLayout.CENTER);
}
Doesnt work, the new button doesnt show up. I tried a call to invalidate() as well but no luck.
How do I trigger a re-evaluation of the layout?
If said function is called more than once, what parts of the layout/buttons do I need to call dispose() on? Any other cleanup I should worry about?
Would this be easier to handle if I don't use the NetBeans designer?
You need to set the layout of the panel before you add the button with BorderLayout.CENTER. Also, you must remove and add the first button again and invoke the revalidate() method on the panel.
Change your addSecond() method as below and it should work.
private void addSecond() {
JButton secondButton = new JButton("Button - 2");
this.setLayout(new BorderLayout());
remove(firstButton);
add(firstButton, BorderLayout.NORTH);
add(secondButton, BorderLayout.CENTER);
revalidate();
}
when you changed the components in a way that changes the layout, you need to trigger the layout manager again by calling revalidate(). You can call it as often as you want.
For simple layouts just calling repaint() may be sufficient.
And actually unless you're doing dynamically changing panels (i.e. adding/removing components on the fly) you should use the netbeans designer, so all the Swing elements are in one place.
-- EDIT --
And you can only put one component into BorderLayout.CENTER per panel. If you put more than one element into the same position of a panel, what gets painted is not well defined, i.e. it may be either of the elements (or both).