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Formatting JButtons in JSplitPane

I'm having trouble getting my JButtons to appear where I want. For some reason all my buttons are appearing in the middle of the Panel when I want it to appear flushed with the top of the Panel, centered. I've tried manipulating different layout positioning such as BorderLayout.NORTH and GridBagConstraints.NORTH however I do not know if I utilizing it on the right components.
Currently my code has A Frame holding a JLayeredPane holding a JSplitPane with two JPanels in it so it has gotten quite confusing.
Do you have any suggestions on how I can get the buttons to appear on the top of the Panel?

I currently have the panel using a GridBagLayout
Read the section from the Swing tutorial on How to Use GridBagLayout for a working example and information about the constraints used by the layout manager.
For some reason all my buttons are appearing in the middle of the Panel
Specifically read the section on the weightx/y constraints, which states that the components will clump together in the center unless you use non-zero values.

Make buttons unresizable

So I was trying to google how to set a default size to JButtons so that they don't grow as the JFrame is resized. I didn't see a setDefaultSize method but the closest one I could find that does a similar job is setMaximumSize(). However, it doesn't seem to work in my situation and I'm guessing it's because I'm using Grid Layout for positioning my buttons in the frame, here's a small piece of my code:
rightPanel.add(ButtonA);
rightPanel.add(ButtonB);
rightPanel.add(ButtonC);
outerPanel.add(leftPanel);
outerPanel.add(rightPanel);
getContentPane().add(outerPanel);
Here's a picture of what happens:
I would also like to have my buttons in the middle of the right panel when I'm resizing (just like they are now but a lot smaller). Any idea of how I can fix this? I'm assuming that I have to use another layout or something.
Thanks
EDIT: I modified my code to use BoxLayout but it does not seem to put the buttons in the middle. The X Alignment is working but Y Alignment is not doing anything:
ButtonA.setAlignmentX(CENTER_ALIGNMENT);
ButtonA.setAlignmentY(CENTER_ALIGNMENT);
ButtonB.setAlignmentX(CENTER_ALIGNMENT);
ButtonB.setAlignmentY(CENTER_ALIGNMENT);
ButtonC.setAlignmentX(CENTER_ALIGNMENT);
ButtonC.setAlignmentY(CENTER_ALIGNMENT);
JPanel rightPanel = new JPanel();
rightPanel.setLayout(new BoxLayout(rightPanel, BoxLayout.Y_AXIS));
rightPanel.add(ButtonA);
rightPanel.add(ButtonB);
rightPanel.add(ButtonC);
outerPanel.add(leftPanel);
outerPanel.add(rightPanel);
getContentPane().add(outerPanel);
EDIT2: Fixed with vertical glue.

A GridLayout will always resize the components to fill the space available.
Try using a vertical BoxLayoutinstead. See the section from the Swing tutorial on How to Use Box Layout for more information and examples.

Encapsulate each JButton in a JPanel with a FlowLayout, and then add those FlowLayout JPanels to the rightPanel instead of the JButtons themselves. This will allow you to keep your evenly spaced buttons, but won't make them expand to take up the entire space that the parent container has available.
If you don't want them evenly spaced, but to be three consecutive buttons one after another top down, you can make the right panel have a BorderLayout, add a sub panel to the north area of the BorderLayout with the original GridLayout that the right panel had, and then add those FlowLayout panels containing the JButtons.

How to enlarge java swing panel

I create some panel with a lot of components as images text ... . Now I have one problem. Customers tell me that panel is too small. Is there some option to enlarge this whole panel or I have to enlarged components one by one ?
UPDATE:
from this:
to this:

everything depends of used LayoutManager,
Is there some option to enlarge this whole panel or I have to enlarged
components one by one
-> no, basically this is reason why LayoutManager exists there, most of them there are created especially for this reasons, GridLayout, GridBagLayout, BoxLayout (maybe without glue), BorderLayout and todays MigLayout are best way how to do it

it depends, if you have a GridLayout or some Layout witch set all the components with some order, for example, all the components at the same distance or all the components like a Matrix, if you enlarge the panel, all the components will enlarge with it. If not, you have to enlarge by hand.

Why does only the last JPanel I add to a JFrame resize?

So I am working on a GUI application using the swing framework. In short, I have 3 JPanels that act as different views of my application. Now the problem is that no matter the order I add the JPanels to my JFrame, only the final JPanel I add resizes when I switch to that view.
Some relevant bits of code:
When creating the window, I first create each individual JPanel, and add it to the JFrame:
JPanel newPanel = new SomeClassExtendingJPanel();
this.jframe.add(newPanel);
Next, whenever I switch between views of the application, I hide the panel that is currently active:
jframe.validate();
jframe.repaint();
oldPanel.setVisible(false);
And then activate the to be shown panel:
jframe.validate();
jframe.repaint();
newPanel.setVisible(true);
Does anyone know what could be wrong?

To resize the JFrame with each swap, you could call pack() on it, but this is kludgy having a GUI resize all the time. A better solution is to use the mechanism that Swing has for swapping views -- a CardLayout. This will size the container to the largest dimension necessary to adequately display all of the "card" components.
Check out the CardLayout tutorial and the CardLayout API for more on this.

JFrame's ContentPane has implemented BorderLayout by Default, and there is possible to put only one JComponents to the one Area,
you have to change used LayoutManager or put another JPanels to the other Areas

Can a layout manager spawn several JPanels?

I have to build a rather large form with many controls. The controls are divided in basic controls/settings and extended controls/settings. The user can decide if he wants to see only the basic or both basic and extended controls.
I've dropped all extended controls onto their own JPanel so that I can easily switch between the two views by showing or hiding this panel.
Currently I'm using GroupLayout and what happens is that the controls on different panels are not aligned:
Label aaa: Text field
Label a: Text field
Label aaaaaa: Text field
----------------------------
Label b: Text field
Label bbb: Text field
Label bb: Text field
Unfortunatly I found now way to "synchronize" the layouts of the two panels (except using AbsoluteLayout and fixed control coordinates)
Is there any way to achive this?
Is my whole design flawed?
EDIT: If it is possible I would like to keep the GroupLayout manager.

As far as I know, no Swing LayoutManager (from JRE or open source) can span several panels.
I am currently working on such a feature (which I called "layouts synchronization") for my DesignGridLayout project, but it is not something easy to implements (I have started about 2 weeks ago and I still don't see exactly if and when I will get to something interesting, but I still have high hope for it;-))
One option you could check would be to add all components to the same panel (with just one GroupLayout then) and hide/show them based on user's selection. Hopefully, GroupLayout will adapt the size to the situation (after calling pack()).
If GroupLayout behaves well, then it would just be a matter of calling pack() each time after user changes his selection to show/hide extended fields.
Else you would have to manually set the size of your panel every time the user changes his selection.

Probably the easiest (good) way to do it is to add all the components to the main panel. Set the subpanels to non-opaque, and add the also to the main panel. The main panel the needs optimised drawing to be switched off.
Another technique is to add a spacer component. To the bottom panel add a component in the same column as the labels which dynamically takes the width component of its various size methods from the top labels. Do the same in reverse to the top panel.

I think there is no way to do it with the standard layout managers. You'll probably have to write your own layout manager, but it shouldn't be too hard if you subclass GroupLayout.

You could use GridLayout instead of GroupLayout which will give you uniform spacing between the columns

If you want to keep them in separate panels with separate layouts:
Iterate over all of the labels that you add, and find the maximum preferred width of each.
Iterate a second time, and set the preferred size to that each label's preferred height, but the maximum width.

This is the explanation of th GridLayout. This will set every component to the size, you expect it. With the GridData object you can specify how the components are ordere.
Examples
(source: sun.com)