Need help with Layouts in Swing - java

I'm using Java Swing and I have the following problem:
I have a class TnaiPanel that extends JPanel. In this class I am creating 3 components and then lay them out in a horizontal line using a BoxLayout.
Also, I have a class TnaimDinamimPanel that also extends JPanel. This class contains multiple occurances of TnaiPanel, layed out vertically using a BoxLayout.
Also, I have a class MainFrame that extends JFrame. This frame contains a menu-bar and one main panel. The main panel can change (when choosing a certain menu-item, I create a new panel and set it to show as the main panel of the frame).
Now, for some reason I get "BoxLayout can't be shared" when I add the newly created TnaimDinamimPanel to the components of the frame.
I don't mind using different layout objects.
The result I want to get is a sort of "table" of components, where each TnaiPanel will have fixed component sizes and spacing, essentially serving the role os a "row" in the "table".
Thanks,
Malki.

You probably create only a single BoxLayout instance. Create a new one each time you need one (i.e. one per TnaiPanel, one per TnaimDinamimPanel and probably one per MainFrame).

To answer the second part of your question, ie "having a table of components", I would say that you can't do it with different panels, except if you start setting the individual min, pref and max sizes of components and panels, which is highly unadvised.
If you need to have correct alignment as in a table of components, then you need to put all your components in one panel, which also means you need to use only one layout. However, the only default swing layout that can allow you to do what you want is the GridBagLayout. Actually the GroupLayout (java 6) would also fit the bill but it absolutely requires a graphical designer (eg the one within netbeans).
If, like me, you are allergic to builders, then you'd better use one 3rd-party LayoutManager that is intended to be use programmatically (I would not consider GridBagLayout to be in this category although I have already used it that way in the past).
MigLayout (as suggested by Skeptic) is one option. Another option is DesignGridLayout which might fit your purpose better and is easier to use than MigLayout.

Try MiGLayout instead.

Related

How to "merge" two JFrames together?

I am desinging a GUI in Java using Swing.
I have two JFrames in my class which I would like to merge into one window, so that when the program is launched, only one window appears. However, my specific needs impose a specific layout constraint: I need to have half of my GUI displaying two components (a JTextArea component, and a JTextPane component), and the other half displaying the third one (an Image).
I can get them to all work singly, but if I try to combine them into a "super-frame" to hold them all, it doesn't work.
I am wondering is there any other way to achieve this effect.
Any help is much appreciated, thank you!
I think it is not possible to merge JFrames and you can instead use JPanels

Creating set of JButtons according to retrieved database values

I'm working on a POS system for a fast food restaurant. I've developed Adding, updating and deleting products using a MySQL Database. Now I need to create the POS GUI (using SWING) which the cashier uses to create the bill. The interface I have in mind is like what MacDonald's uses, there's a set of buttons with the product images. (I have stored BLOBS of products successfully)
example image :
I have no idea on how to accomplish this, it would be awesome if its possible to generate a set of dynamic Jbuttons which gets the image of a product along with the name and price. Is this the best way to accomplish this? and how do I achieve this? A few details to put me on the correct path will be greatly appreciated!
Thanks.
You have at least four containers, the top row, the bottom row and each row containing a separate container in the middle (for the buttons).
The basic layout for the rows might be a GridLayout, each row would probably use a BorderLayout with the nav buttons in the WEST and EAST positions. CENTER container could use a GridLayout, but won't give you the look you're after. You could use a FlowLayout and even a GridBagLayout, but you'd need to ensure the size of the buttons where correct for your needs
On the left I see a JTable and two JPanels, containing the buttons, held together with a GridBagLayout.
On the right I see a JList. See How to Use Lists for more details. You'll probably also want to have a look at Concepts: Editors and Renderers and Writing a Custom Cell Renderer for details about how you could customise the look of the cells and How to Write a List Selection Listener for details about how to determine when the user changes the selection
Together, they are probably maintained by a GridBagLayout within a single container for ease of use
Along the button is probably another container using a GridBagLayout.
Altogether, they are probably held together by a GridBagLayout
Have a look at Laying Out Components Within a Container, How to Use GridBagLayout, How to Use BorderLayout and How to Use FlowLayout for more details
You will need to look into the GridLayout.
In your case, it might be a little bit more complex since you have multiple grids, some of which seem to be nested within each other.
You should be able to allocate the grid dynamically and then leave it to the layout manager to distribute things evenly over the page.
Depending on the complexity of your layout, it might also be a good idea to look into the GridPane provided by JavaFX.
Hi I look for you this problem and I find this solution ;
http://www.javasrilankansupport.com/2012/06/create-dynamic-jbutton-with-image-and.html

Proper Swing Design

I've heard that putting the same-level component on top of another same-level component is bad practice.
I'm talking about JPanels in this case. I currently divide everything into separate JPanels where each has its own layout, and then I add them to the main content pane (JPanel). I feel like this way is much easier than having to configure a layout that will work for all my components that can be all over the place. Is my logic flawed?
There is nothing wrong with having panels inside of panels. However, if you are doing a lot of that, you may want to consider a layout manager (my favorite is MiGLayout) that supports fairly complex arrangement of controls without using tons of nested panels.
At the end of the day, use a composition that makes it easier for you to maintain your code. If you have groupings of controls that are independent of each other, then having them in separate panels is good design - it allows you to split that panel out (for testing, or even for creative windowing in the UI). If the sets of controls are intrinsically tied to each other, consider a single panel with an advanced layout manager.
In some cases, you'll have a small amount of binding between two panels (classic example is one panel with a list and another panel with a detail view for the selected item in the list). In this case, I generally use two separate panels, and two separate presentation models, then bind the current selected item in one model to the parent of the inspector panel. But if you find that you are using values from multiple panels for things like validation, data storage, etc... then you may have things split into too many panels.
I've done a lot of this over the years, and the position I've settled on is to compose my UIs along logical lines of the underlying presentation models that back the views. Very rarely do I let the layout of the UI drive how many panels I use, etc... - MigLayout (and I'm sure there are others) make even complex UI layouts fairly straightforward, and it's much better to design the classes for the view and model in a way that make the code easier to test and maintain.

Using CardLayout in NetBeans GUI Builder

I am using the NetBeans 7.2.1 GUI Builder. I could do all of this by hand. Instead, I am using my current project to learn how this tool works so that I can make an informed decision of when to use it in the futre (if at all).
Now with help of archived questions here, I have figured out how to change the LayoutManager to a CardLayout. I have also added three JPanels to the layout (although, there seems to be a bug...maybe a question about that later). The first JPanel displayed by the CardLayout will have two buttons. Each button will cause the CardLayout to display one of the other two JPanels. To do this, I found that I can use CardLayout#show(Container, String).
I need to know what the value of the String is for each JPanel. Doing some further research, I found that NetBeans generates a line of code such as
getContentPane().add(addCardsPanel, "card2");
So I can use "card2" to show addCardsPanel. It would be convenient to use a more applicable String. Will NetBeans allow me to set this identifying String to whatever value I wish? If so, how do I do it?
In the Navigator window select the panel you want.
In the Properties window scroll down to the Layout group. You'll see a Card Name property. Knock your self out ;)

Swing GUI components too tighly packed

In the Java Swing app I made it seems to me that all the component are too tightly packed.
In QT one can specify padding and margins for the layout.
Is there something similar for swing?
alt text http://img12.yfrog.com/img12/9612/screenshotscreenerconfi.png
Here is a screen shot of my application that I thing is too tight (is it? what do you think?.
Thanks.
Take a look to the GridBagLayoutManager. Its the most compex layout manager but everything can be acomplished whith it.
It uses the GridBagConstraintObject which has the inset property, it specifies the separation to the top, bottom, left and right components.
example: GridBagConstraintObject.insets.left=20
You could use MiGLayout as your layout manager. It allows all kinds of customizations, including margins/paddings.
You could achieve a much better layout for the example above by using DesignGridLayout in just a couple of lines of code (one per row in your layout). DesignGridLayout will automatically use the correct spacing for the runtime platform.
besides I would highly suggest that you DON'T use TitledBorders in your form because it prevents ANY LayoutManager (as advanced as it may be) from automatically aligning correctly the various components across different groups. Instead you could use a JLabel with a JSeparator (there are examples in DesignGridLayout, but this works with any other LayoutManager).
Since Java 1.6 swing there is a new GroupLayout manager that make this kind of works easier.
For instance there is a method: setAutoCreateGaps() that:
...you add two components to a SequentialGroup a gap between the two components is automatically be created...
For instance:
What LayoutManager are you using? Adding margins is quite easy, it depends however on the specific LayoutManager used.
FormLayout is another good layout manager. With a good GUI editor like JFormDesigner it makes GUI building easy enough. JFormDesigner actually automatically adds sufficient padding in most cases. I have to recommend against using GridBagLayout. It does the job alright, but is very complex which makes it difficult to use and maintain.

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