I'm relatively new to Java and I'm trying to make some kind of quiz. I created 3 JFrames, all in the same package. On my main frame, there are two buttons (one for the english version and the other one for the german version). I want to switch JFrames after pressing these buttons (so that I can, by pressing "English", see and interact with my english quiz frame). Looking it up didn't help me the slightest, because I'm not really experienced with it. Is it even possible to do it like this? If not, how could I do it?
The standard approach is to use the Card Layout, which allows you to use the same JFrame as you populate it with different things at different points in your application. So initially, your JFrame would show the loading screen, then the user presses a button and you load a new set of components without discarding the current JFrame you have. In some cases, you might also need to make some size adjustments.
It is difficult to say without seeing any code, but usually, what is done is that you do something like so:
new Frame(args);
this.dispose();
The code above assumes that the constructor of Frame takes care of launching and making the components visible. The this.dispose(); disposes of the current JFrame (assuming your class extends JFrame).
You have two buttons in your frame 1 right? So first, double click the button which says "English". Lets say the variable name for that button is jButton1. Inside that button type this.
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
this.dispose();
EnglishFrame eng = new EnglishFrame();
eng.setVisible(true);
}
Then double click the other button which says "German" (jButton2). Inside that type this.
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
this.dispose();
GermanFrame german = new GermanFrame();
german.setVisible(true);
}
this.dispose() - This will cause the jFrame window to close
Then you create an object of the other two forms. (In your case the form for English and Germany)
.setVisible(true) - This will show you the form.
Create a single Jframe window. After that create JPanels with all the compenents such as buttons, textfields and labels you want. Make sure the panel is the same size as your Jframe. Panel's work about the same as JFrame's, code wise.
This code will stitch everything together for you:
panel.setSize(Jframe.getSize()) //That wont
panel.add(button); //Just remember you need to add more code to position the buttons correctly.
//If you using netbeans builder:
//You just have to use this one line in the constructor/intialiser method
frame.add(panel); //This will add the panel to the Jframe/Window
//No need to add extra code for positioning.
If you want to swap between the panels. In the button press method, use this
frame.setContentPane(panel); //panel = panel you want to change too.
frame.repaint(); //Ensures that the frame swaps to the next panel and doesn't get stuck.
frame.revalidate(); //Ensures that the frame swaps to the next panel and doesn't get stuck.
When you first start the java application you have to set the content pane or else it will appear as a blank window.
frame.setContentPane(panel); //Starting Panel
frame.setVisible(true); //Make the frame visible
Sorry if the explanation is bad, I don't have enough time to explain it fully.
Related
i have 5 jFrames in my java project. And i want to make like a Main Menu.
I mean, i want that the program starts with a jFrame and when i click a button insteand of open the jFrame, all the elements like labels, buttons and tables are being shown in my principal jFrame.
And if i click other button the main frame will clean and charge other jframe.
It is possible? im programming with java jdk 8 and netbeans.
Thanks
Edit:
I think who marked duplicate didn't understand my question. I don't want to open or close the frame, or other frames, I want to load the structure and components of several in the same frame. Please read my question before you start complain that is duplicated
i have 5 jFrames in my java project.
And that's a problem.
And i want to make like a Main Menu. I mean, i want that the program starts with a jFrame and when i click a button insteand of open the jFrame, all the elements like labels, buttons and tables are being shown in my principal jFrame. And if i click other button the main frame will clean and charge other jframe.
Yes this can be solved by getting the contentPane (usually a JPanel) from the JFrame whose content you want to display within the currently displayed JFrame, and making it the contentPane of the displayed JFrame, for example:
// create the new JFrame, the one whose content you wish to display
NewJFrame newJFrame = new NewJFrame();
// get its contentPane
Container newContentPane = newJFrame.getContentPane();
// add this content pane into the displayed JFrame
displayedJFrame.setContentPane(newContentPane);
// revalidate and repaint the JFrame so that its new data is well displayed
displayedJFrame.revalidate();
displayedJFrame.repaint();
// displayedJFrame.pack(); // and you might need to do this if sizes are way off
But this extra gymnastics is bulky, prone to bugs and unnecessary. You are painting yourself in a corner by having your class extend JFrame, forcing you to create and display JFrames, when often more flexibility is called for. In fact, I would venture that most of the Swing GUI code that I've created and that I've seen does not extend JFrame, and in fact it is rare that you'll ever want to do this. More commonly your GUI classes will be geared towards creating JPanels, which can then be placed into JFrames or JDialogs, or JTabbedPanes, or swapped via CardLayouts, wherever needed. This will greatly increase the flexibility of your GUI coding.
For this situation what I recommend is that you do that, that your GUI classes create JPanels, and that you add the ones that you want to swap to a JPanel that uses a CardLayout. And then whenever you want to show a different "card", call show(...) on the CardLayout object, passing in the JPanel that uses it, as well as the String key that was used when adding the "card" JPanel to the CardLayout-using JPanel. This is all well-explained in the CardLayout Tutorials.
Other useful links:
For rationale on why to avoid manually swapping please see: What's so special about CardLayout vs manual adding/removal of JPanels?
For using a CardLayout to help control a "multi-page" application with multiple classes, please see: How to Integrate Multi-page Java Desktop Application from Multiple GUI Classes
So I have a program that at the start only contains an 'add movie' button at the bottom of the frame.
Above it I inserted a scrollpane.
I also made a seperate JPanel form which contains labels and textfields where you have to input the data of the movie.
Every time I click the 'add'-button I want a form to appear inside the scrollpane (next to previously made forms).
So I figured I just needed to do this:
private void AddMovieButtonActionPerformed(java.awt.event.ActionEvent evt) {
MovieForm movie = new MovieForm();
MovieScrollPane.add(movie);
}
But nothing new appears.
I tried validate() and repaint(), but so far these don't seem to work.
I made the interface in Eclipse btw.
Anyone who can help me?
Thanks anyway!
MovieScrollPane.add(movie);
Don't add components directly to the scrollpane. Normally a JPanel is added the the viewport of the scrollpane.
Then, whenever you add a component to a visible GUI the basic code is:
panel.add(...);
panel.revalidate();
panel.repaint();
This makes sure the layout manager is invoked to the preferred size can be recalculated.
Also, follow Java naming conventions. Variable names should NOT start with an upper case characters.
I'm trying to set a variable to be a new JPanel and then add it once a button is pressed, but it is not working and I don't know why.
code:
private void nextButtonActionPerformed(java.awt.event.ActionEvent evt) {
remove(scriptPanel);
scriptPanel = new GemPanel();
add(scriptPanel);
validate();
repaint();
pack();
}
GemPanel is just a JPanel class I made. When I press the next button, it re-sizes the frame to be as small as possible and nothing actually happens. If I re-size it to normal, the original scriptPanel is still there.
What gives?
Instead of trying to remove and add entire panels, a better, less problem prone approach would be to use a CardLayout that will allow to swap views. You can see more at How to use Cardlayout
Also, by the looks of your method signature, it seems you're using the Netbeans builder too. You may also want to take a look at How to Use CardLayout with Netbeans Gui Builder
I'm new to java.I'm creating a swing based UI. I've created 2 frames, each one in separate .java file inside same package.
These two frames represents 2 screens (panels) of application. When Next button in first frame is clicked, it should move to second frame.
When I checked, these two classes are having main method, I think it should be correct way for creating applications. there should be only one main method.
When Next is clicked, I'm trying to make setVisible(false) for main panel of first frame and setVisible(true) for main panel of second frame. But this cannot be done, since the panels within a class are private. Any resolution for the above problem?
As I'm beginner, Can somebody suggest me in how to start up with these kind of applications? what are the guidelines that need to be followed? And please help me in finding documentation related to starting up with the development of such applications.
After going through the answers, My comments are:
I used the following code to go to next panel from first panel, but didn't worked.
private void gotoNextPanel(){
// jPanelFirstScreen.setVisible(false);
JPanelSecondScreen jpanelSecondScreen= new JPanelSecondScreen();
jpanelSecondScreen.setVisible(true);
UpgradeUtilityGUI upgradeUtilityGUI = new UpgradeUtilityGUI();
upgradeUtilityGUI.removeAll();
validate();
repaint();
// upgradeUtilityGUI.add(jpanelSecondScreen);
upgradeUtilityGUI.getContentPane().add(jpanelSecondScreen, "card2");
jpanelSecondScreen.setVisible(true);
validate();
repaint();
}
I'm using netbeans, and 've added two panels to the cardlayout of frame. And when I use the above code to change panels, Nothing is happening, the first panel is still appearing. Can somebody tell me, how to write code for moving from one panel to another when both the panels 've been added to cardlayout of jFrame ?
Use a CardLayout, as shown here (and one frame) as mentioned by others.
When Next is clicked, I'm trying to make setVisible(false) for main panel of first frame and setVisible(true) for main panel of second frame. But this cannot be done, since the panels within a class are private. Any resolution for the above problem?
Make the panels public access level and they will be available from other packages.
One problem in that code snippet is implied by the line:
UpgradeUtilityGUI upgradeUtilityGUI = new UpgradeUtilityGUI();
It goes out of scope before ever being added to a container. Also, their should be no need to remove anything when adding a new card to the layout, and no need to call repaint().
If your application is as simple as having only two panels you shouldn't create two JFrames. You should create a JFrame with two JPanel each of them contains the neccessary information for you. If you are ready with your first panel you can call setVisible(false) on it, and call setVisible(true) on the 2nd frame. It is the one of the most easy-to-understand solution.
But, it only depends on you if it is good for you or you would like to use some more detailed solution.
Don't use two or more JFrames, nor with separated and compiled Jar files, this is road to the hell, better would be look at CardLayout,
What you should do is have a single JFrame for the application, then you add and remove JPanels as you want to move between screens.
Each of your JPanels should basically have the following...
1. A JButton called "Next"
2. A ButtonListener for each button, that tells the JFrame to load panel2, panel3, etc.
As part of the ButtonListener, you basically just want to call something like JFrame.removeAll() to remove the existing panel, then JFrame.add(JPanel) to add the next panel.
By having 1 JFrame, you also only have 1 main() method.
I'm writing a simple slide program. In that program, I show small thumbnails of all slides in a new jpanel. In that new jpanel, after clicking 2 thumbnails, it should swap them. However, after swaping them, jpanel is not refreshing. If I create new jpanel by calling createAndShowGUI() function, it is ok, but then I need to close the old jpanel.
Below is my simple class,
http://docs.oracle.com/javase/tutorial/uiswing/examples/layout/GridLayoutDemoProject/src/layout/GridLayoutDemo.java
And in my main program if I click "slide sorter mode" button handler compile the following code
gridLayoutDemoObject.createAndShowGUI();
What is the solution and how should I make it ?
Thanks.
You didn't provide enough information to indicate how you display the images or how you swap them so its hard to give a proper answer.
I would display the images by using a JLabel (or JButton without a Border). Then when you can just use setIcon(...) to swap icons and the label will repaint itself.
Next time post an SSCCE that demonstrates the problem so we don't have to guess what you are talking about.