I got my program, that can connect to a Database working! ( Hooray )
But now, I ran into a new problem. I read that using multiple JFrame windows (and closing the old one) is not user friendly, and a bad learning habit.
So now I am wondering, is there a way to switch between Panels, or something similar?
Example:
JFrame with Login & Password. -- Users logs in, goes to the next 'screen' where he or she can see the Database info, cause he or she logged in!
What should I use, any good methods out there?
you may want to check CardLayout
The simple answer is yes you can. The idea is to have a localized class that contains a method that outside classes can call passing a jPanel then simply add that panel to your jFrames content pane (which in turn will remove the other panel). There are many ways to go about this and I hope you find one that works and I hope this answer helps you as well.
Here is the procedure I generally follow. I create and open a new Frame and make the parent frame invisible. Again when child frame is closed I make the parent frame visible. I am using this procedure for a long time and not facing any problem.
This is the piece of the code executed when login button is clicked.
...
setVisible(false); //Hide the login page
DBPage page=new DBPage(this, value1); // DBPage is another JFrame
page.setVisible(true);
I feel this much of code is enough to understand.
JLayeredPane might work.
http://docs.oracle.com/javase/8/docs/api/javax/swing/JLayeredPane.html
You could have several layers on top of each other, the login screen, etc. and show the layer that is most relevant at the time.
A previous question may prove useful:
Java Swing - how to show a panel on top of another panel?
Closed. This question is opinion-based. It is not currently accepting answers.
Want to improve this question? Update the question so it can be answered with facts and citations by editing this post.
Closed 8 years ago.
The community reviewed whether to reopen this question 1 year ago and left it closed:
Original close reason(s) were not resolved
Improve this question
I'm developing an application which displays images, and plays sounds from a database. I'm trying to decide whether or not to use a separate JFrame to add images to the database from the GUI.
I'm just wondering whether it is good practice to use multiple JFrame windows?
I'm just wondering whether it is good practice to use multiple JFrames?
Bad (bad, bad) practice.
User unfriendly: The user sees multiple icons in their task bar when expecting to see only one. Plus the side effects of the coding problems..
A nightmare to code and maintain:
A modal dialog offers the easy opportunity to focus attention on the content of that dialog - choose/fix/cancel this, then proceed. Multiple frames do not.
A dialog (or floating tool-bar) with a parent will come to front when the parent is clicked on - you'd have to implement that in frames if that was the desired behavior.
There are any number of ways of displaying many elements in one GUI, e.g.:
CardLayout (short demo.). Good for:
Showing wizard like dialogs.
Displaying list, tree etc. selections for items that have an associated component.
Flipping between no component and visible component.
JInternalFrame/JDesktopPane typically used for an MDI.
JTabbedPane for groups of components.
JSplitPane A way to display two components of which the importance between one or the other (the size) varies according to what the user is doing.
JLayeredPane far many well ..layered components.
JToolBar typically contains groups of actions or controls. Can be dragged around the GUI, or off it entirely according to user need. As mentioned above, will minimize/restore according to the parent doing so.
As items in a JList (simple example below).
As nodes in a JTree.
Nested layouts.
But if those strategies do not work for a particular use-case, try the following. Establish a single main JFrame, then have JDialog or JOptionPane instances appear for the rest of the free-floating elements, using the frame as the parent for the dialogs.
Many images
In this case where the multiple elements are images, it would be better to use either of the following instead:
A single JLabel (centered in a scroll pane) to display whichever image the user is interested in at that moment. As seen in ImageViewer.
A single row JList. As seen in this answer. The 'single row' part of that only works if they are all the same dimensions. Alternately, if you are prepared to scale the images on the fly, and they are all the same aspect ratio (e.g. 4:3 or 16:9).
The multiple JFrame approach has been something I've implemented since I began programming Swing apps. For the most part, I did it in the beginning because I didn't know any better. However, as I matured in my experience and knowledge as a developer and as began to read and absorb the opinions of so many more experienced Java devs online, I made an attempt to shift away from the multiple JFrame approach (both in current projects and future projects) only to be met with... get this... resistance from my clients! As I began implementing modal dialogs to control "child" windows and JInternalFrames for separate components, my clients began to complain! I was quite surprised, as I was doing what I thought was best-practice! But, as they say, "A happy wife is a happy life." Same goes for your clients. Of course, I am a contractor so my end-users have direct access to me, the developer, which is obviously not a common scenario.
So, I'm going to explain the benefits of the multiple JFrame approach, as well as myth-bust some of the cons that others have presented.
Ultimate flexibility in layout - By allowing separate JFrames, you give your end-user the ability to spread out and control what's on his/her screen. The concept feels "open" and non-constricting. You lose this when you go towards one big JFrame and a bunch of JInternalFrames.
Works well for very modularized applications - In my case, most of my applications have 3 - 5 big "modules" that really have nothing to do with each other whatsoever. For instance, one module might be a sales dashboard and one might be an accounting dashboard. They don't talk to each other or anything. However, the executive might want to open both and them being separate frames on the taskbar makes his life easier.
Makes it easy for end-users to reference outside material - Once, I had this situation: My app had a "data viewer," from which you could click "Add New" and it would open a data entry screen. Initially, both were JFrames. However, I wanted the data entry screen to be a JDialog whose parent was the data viewer. I made the change, and immediately I received a call from an end-user who relied heavily on the fact that he could minimize or close the viewer and keep the editor open while he referenced another part of the program (or a website, I don't remember). He's not on a multi-monitor, so he needed the entry dialog to be first and something else to be second, with the data viewer completely hidden. This was impossible with a JDialog and certainly would've been impossible with a JInternalFrame as well. I begrudgingly changed it back to being separate JFrames for his sanity, but it taught me an important lesson.
Myth: Hard to code - This is not true in my experience. I don't see why it would be any easier to create a JInternalFrame than a JFrame. In fact, in my experience, JInternalFrames offer much less flexibility. I have developed a systematic way of handling the opening & closing of JFrames in my apps that really works well. I control the frame almost completely from within the frame's code itself; the creation of the new frame, SwingWorkers that control the retrieval of data on background threads and the GUI code on EDT, restoring/bringing to front the frame if the user tries to open it twice, etc. All you need to open my JFrames is call a public static method open() and the open method, combined with a windowClosing() event handles the rest (is the frame already open? is it not open, but loading? etc.) I made this approach a template so it's not difficult to implement for each frame.
Myth/Unproven: Resource Heavy - I'd like to see some facts behind this speculative statement. Although, perhaps, you could say a JFrame needs more space than a JInternalFrame, even if you open up 100 JFrames, how many more resources would you really be consuming? If your concern is memory leaks because of resources: calling dispose() frees all resources used by the frame for garbage collection (and, again I say, a JInternalFrame should invoke exactly the same concern).
I've written a lot and I feel like I could write more. Anyways, I hope I don't get down-voted simply because it's an unpopular opinion. The question is clearly a valuable one and I hope I've provided a valuable answer, even if it isn't the common opinion.
A great example of multiple frames/single document per frame (SDI) vs single frame/multiple documents per frame (MDI) is Microsoft Excel. Some of MDI benefits:
it is possible to have a few windows in non rectangular shape - so they don't hide desktop or other window from another process (e.g. web browser)
it is possible to open a window from another process over one Excel window while writing in second Excel window - with MDI, trying to write in one of internal windows will give focus to the entire Excel window, hence hiding window from another process
it is possible to have different documents on different screens, which is especially useful when screens do not have the same resolution
SDI (Single-Document Interface, i.e., every window can only have a single document):
MDI (Multiple-Document Interface, i.e., every window can have multiple documents):
I'd like to counter the "not user friendly" argument with an example that I have just been involved with.
In our application we have a main window where the users run various 'programs' as separate tabs. As much as possible we have tried to keep our application to this single window.
One of the 'programs' they run presents a list of reports that have been generated by the system, and the user can click on an icon on each line to pop open a report viewer dialog. This viewer is showing the equivalent of the portrait/landscape A4 page(s) of the report, so the users like this window to be quite big, almost filling their screens.
A few months ago we started getting requests from our customers to make these report viewer windows modeless, so that they could have multiple reports open at the same time.
For some time I resisted this request as I did not think this was a good solution. However, my mind was changed when I found out how the users were getting around this 'deficiency' of our system.
They were opening a viewer, using the 'Save As' facility to save the report as a PDF to a specific directory, using Acrobat Reader to open the PDF file, and then they would do the same with the next report. They would have multiple Acrobat Readers running with the various report outputs that they wanted to look at.
So I relented and made the viewer modeless. This means that each viewer has a task-bar icon.
When the latest version was released to them last week, the overwhelming response from them is that they LOVE it. It's been one of our most popular recent enhancements to the system.
So you go ahead and tell your users that what they want is bad, but ultimately it won't do you any favours.
SOME NOTES:
It seems to be best practice to use JDialog's for these modeless windows
Use the constructors that use the new ModalityType rather than the boolean modal argument. This is what gives these dialogs the task-bar icon.
For modeless dialogs, pass a null parent to the constructor, but locate them relative to their 'parent' window.
Version 6 of Java on Windows has a bug which means that your main window can become 'always on top' without you telling it. Upgrade to version 7 to fix this
Make an jInternalFrame into main frame and make it invisible. Then you can use it for further events.
jInternalFrame.setSize(300,150);
jInternalFrame.setVisible(true);
It's been a while since the last time i touch swing but in general is a bad practice to do this. Some of the main disadvantages that comes to mind:
It's more expensive: you will have to allocate way more resources to draw a JFrame that other kind of window container, such as Dialog or JInternalFrame.
Not user friendly: It is not easy to navigate into a bunch of JFrame stuck together, it will look like your application is a set of applications inconsistent and poorly design.
It's easy to use JInternalFrame This is kind of retorical, now it's way easier and other people smarter ( or with more spare time) than us have already think through the Desktop and JInternalFrame pattern, so I would recommend to use it.
Bad practice definitely. One reason is that it is not very 'user-friendly' for the fact that every JFrame shows a new taskbar icon. Controlling multiple JFrames will have you ripping your hair out.
Personally, I would use ONE JFrame for your kind of application. Methods of displaying multiple things is up to you, there are many. Canvases, JInternalFrame, CardLayout, even JPanels possibly.
Multiple JFrame objects = Pain, trouble, and problems.
I think using multiple Jframes is not a good idea.
Instead we can use JPanels more than one or more JPanel in the same JFrame.
Also we can switch between this JPanels. So it gives us freedom to display more than on thing in the JFrame.
For each JPanel we can design different things and all this JPanel can be displayed on the single JFrameone at a time.
To switch between this JPanels use JMenuBar with JMenuItems for each JPanelor 'JButtonfor eachJPanel`.
More than one JFrame is not a good practice, but there is nothing wrong if we want more than one JFrame.
But its better to change one JFrame for our different needs rather than having multiple JFrames.
If the frames are going to be the same size, why not create the frame and pass the frame then as a reference to it instead.
When you have passed the frame you can then decide how to populate it. It would be like having a method for calculating the average of a set of figures. Would you create the method over and over again?
It is not a good practice but even though you wish to use it you can use the singleton pattern as its good. I have used the singleton patterns in most of my project its good.
I am somewhat new to coding and I need a little help. I am making a program where you start in the main menu. In the main menu there is an options button you can click on that will open a new jframe with the options. I was wondering if there was a way so that you would have to use the new JFrame before using the older (or main) one.
Take a look at How to Make Dialogs.
A modal dialog is one that must be dismissed (closed) before you can interact with program again (an example might be the open/save dialog of Word or your web browser)
But you should also have a read through The Use of Multiple JFrames: Good or Bad Practice? first...
Alternatively, you could use a CardLayout, which would allow you to switch between views from within the same window
You could also use a JTabbedPane which will allow you to have your views presented on the screen and accessible via a "tab", meaning the user can only interact with a single view, but they can navigate to a different view by clicking the tab they want.
My program consists of 3 main 'sections'. Main function, Login form and App form. The main function should do something like: Open Login form, wait for it to close, then open App form. I can't get the waiting part to work, or rather, I don't know how I would go around doing that.
I was told by someone to use a JDialog instead and use setModal(true), but with that approach the Login form wouldn't appear on the taskbar, which is terrible in my opinion.
Another thing I considered was to open the App from inside the Login after it closes, but that feels like bad design since that'd make the Login form non-reusable.
So, please, what would you suggest?
Why must the login appear on the task bar, since the main app will be there, and you don't want more than one task bar item for an individual program. Your best option may be to use a modal JDialog.
Another option is to use CardLayout to swap "views".
A third option is to use a JFrame if you must but attach a listener to it, a WindowListener I believe, to respond to its close event.
Regardless of which route you go, your login gui should be a JPanel so that you can place it anywhere you wish and then change your mind later.
I have developed my Java code in Netbeans, and now I want to develop the GUI for my application.
The application communicates with a server, so it's going to have a login frame for sure. After that there will be a main frame. From the main frame the user can choose where to go and as you can understand there will be a lot of frames.
I have already developed a version of the application where there are a lot of frames and using the "setVisible()", but I want something better looking. I want a stable frame and inside it, changing the panels or something similar.
How would I do this?
You might use JInternalFrames if you like them, or simply use a main panel with a CardLayout, and display the appropriate card depending on the clicked menu item, or the selected JTree node (as it's done in Windows Explorer and similar applications).
Use the Swing tutorial to get you started.
You can, at any time, make any Container object a JFrame's ContentPane. You can also add and remove Containers from any other Container. If you want a user to be able to jump to any of a dozen panels at any time, CardLayout, as suggested in another answer, is easily the best route. If, however, you intend to lead the user along a somewhat controlled path, you can start with a login JPanel. When that's done, you can create the next panel (a JPanel or something else), add it, and dispose of the first one. And so on until the user exits.
If the transition from one panel to another affects nothing else in the program besides the two panels and the parent Container (JFrame or descendant), this is probably the way to go. If a bunch of other places in the program need to know about the change, you'll want a more centralized mechanism, maybe using CardLayout.