JPanels one above the other - java

I want to design a jFrame where there are three jButtons and a set of three jpanels one above the other. When we call a jPanel from the respective jButton , that pane will be displayed. It would appear to the user as if the same portion of the jFrame is displaying the content to be shown on clicking each jButton.But when i am trying to set the jPanels one above the other, they are being shown side by side thus elongating the jFrame horizontally. What should i do to put one jPanel over the other? Any other idea than jPanel which should do the work i intend to do would also be help !!

Your behavior sounds like you are using a FlowLayout. This will not "layer" anything. Instead us a CardLayout, which does exactly what you are trying to accomplish. You call method like show, next, and previous to navigate the panels. See How to Use CardLayout for more details.
Also there are probably hundreds of other examples here on so. Go through the cardlayout questions.
[Tip: navigate the different tabs like "votes" and "frequent" to filter to some of the better posts]
Here's one that uses the show() method to switch between two panels by name.

Related

JFrames inside JFrames

I currently have build an application where I use multiple frames.
But it would be nice if I could use the frames I used all in just 1 frame.
Like in the image below.
So if you press the left button "Speler Overzicht" that it will show the users in the right panel and I still have my buttons in the left panel.
Generally speaking, it's a very bad idea to base you UI classes on JFrame, as it locks you into a single use case, meaning you can't add the UI component (frame) to other containers.
I better solution is to base your UI components on JPanels, which then allows you to add them to where ever you need them. It also makes life easier to extend them, but that's another story.
To allow the user to move between multiple views, you can use either a CardLayout or JTabbedPane depending on your needs
See How to Use CardLayout and How to Use Tabbed Panes for more details
Use JPanels instead.
buttonPanel=new JPanel();
overzichtPanel=new JPanel();
buttonPanel.add(button);// do this for every button
overzichtPanel.add(componentsYouWantToAdd);// replace with your variables of course
frame.add(buttonPanel, BorderLayout.WEST)
frame.add(overzichtPanel, BorderLayout.CENTER)
You cannot put one JFrame inside another. You have a some design choices here. You can change your JFrames to JPanels. This is probably the easiest change. On the other hand, you can look at using Internal Frames instead.

Two JPanels in one JFrame - the second overrides the first

I am trying to create a GUI where I add two JPanels to one JFrame, but the second JPanel I add override the first. In my first JPanel I have a sudoku box, and in the second I want a button. But, since the first one I add always overrides the second, this doesn't work.
My sudoku JPanel uses GridLayout, and this alone works perfectly. The problem is when I try to add the second JPanel (which has a JButton). Since the button needs to be another size than the squares in the sudoku box, I can't add this button to the first JPanel.
Is it possible to solve this using two JPanels, or do I need a different layout? I have read some about GridBagLayout and think this might be a solution, but it's a bit boring to change the whole code for my JPanel which has the sudoku in it.
You could just make another JPanel with an appropriate layout manager, and add the two smaller panels inside it. Having panels inside of panels is a good way to break up your layout into less complex pieces while maintaining better control of resize behavior, etc.

Java multiple GUI windows creation

I have made a simple GUI using a GridLayout(5,3) , it is action performed and it implements action listener as well. The are some calculation and algorithms that working according to what inputs or buttons the user provides. Everything works just fine up to this point.
At some point in my code, the user gets a pop up massage that he is correctly logged in to the system using this common method JOptionPane.showMessageDialog(....) . All i want is, after he press the OK button, is to create an additional form that pop ups, and looks similar to the one above i made with GridLayout(5,3) so that my user can store additional info about him.
I really cant get it to work, and i have no idea how to start this.
Any ideas are very welcomed! Cheers and thanks in advance :)
if add this:
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container pane = getContentPane();
GridLayout grid=new GridLayout(10,1);
pane.setLayout(grid);
it only adds more lines to my gridlayout. And all above buttons and labels remains. How can i get rid of the previous labels and buttons?
You state:
if add this:
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container pane = getContentPane();
GridLayout grid=new GridLayout(10,1);
pane.setLayout(grid);
it only adds more lines to my gridlayout. And all above buttons and labels remains. How can i get rid of the previous labels and buttons?
You have at least three options if you want to swap "views" on the JFrame.
If you want to use the same GUI with the same JTextComponents but have the components empty of text, then you'll need to go through your text components and call setText("") on all of them. If you want to keep the same JButtons and labels but change their text, then similarly you will need to go through all of them calling setText("something else").
If you want totally new components to replace the old ones, the most straight forward way I believe is to use a CardLayout to hold your JPanel that has all your components. When you want to swap the JPanel for another, make sure that the new JPanel has been added to the CardLayout-using JPanel and then call next() on the CardLayout object.
Another way is to manually swap out JPanels held by the JFrame's contentPane by calling removeAll() on the contentPane, then add(nextJPanel) on it, then revalidate(), then repaint().

Simplest process for switching displayed classes that extend JPanel in JApplet

I have several classes which extend jpanel, many of which have parameters in their constructors. Each already contains components, and they need to handle information and pass this information between each other. I would like to display these panels on a website and to my understanding, the best solution is an applet.
I am also given to understand a cardlayout is probably what I need. I have no experience with cardlayout, and I need a way to switch between the panels based on a signal from inside the panels themselves.
For example, clicking the submit button on the login panel will bring up another panel which allows the user to select various options for the next panel to be displayed.
How can I do this?

Java: single frame vs multiple frames

Think about the classic installation process, where you have a "next" button and when you click it the content of the window changes. To represent this situation I thought of two possible solutions:
-when "next" is clicked destroy the current JFrame and create a new JFrame, maybe passing to his constructor useful information (e.g. actual window size, content inserted by the user in the current frame, ...)
-when "next" is clicked remove all the components from the current JFrame and add new components as needed
The first solution looks way better about OOprogramming, because I can keep separate classes for different frames and I can avoid huge methods that empty the frame and repopulate it. However the first solution sounds a bit "dirty" and I should pass lots of parameters to the new frame. To represent this situation I would choose the second solution.
Now think about a menu with an "option" component: in this situation I would create a new JFrame when "option" is clicked, so that I can populate it with option items. Is this a correct solution? Is there a way I can always know which one is the best solution? Are there any solutions I didn't think about?
Destroying the main JFrame would be silly -- not to mention jarring for the user. Just use a single JFrame and change its contents.
To implement an installer wizard, use a single JFrame containing one large JPanel on top and a smaller one containing the "Next", "Back", "Cancel" buttons along the bottom. When the Next or Back buttons are pressed, you replace the large JPanel. You can have many different JPanel subclasses, one for each "page" of the wizard.
There's a LayoutManager called CardLayout which is ideal for implementing this scenario -- it manages a "stack" of components, and only shows one of those components at a time. Use a BorderLayout in the JFrame. Into the center position put a JPanel with a CardLayout. Then add the individual pages of the wizard to that JPanel, so the CardLayout can manage them.
The CardLayout is well suited for this. You just swapout the JPanel contents when the "Next" button is pressed.

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