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Java LayoutManagers with JPanels

I'm really struggling with creating a complicated layout. Here is a picture of what I want in the end:
(source: fbcdn.net)
I've attempted to divide and conquer, creating small panels and putting those in other panels. At first I figured a borderlayout for the main container panel which is in the initial JFrame, with a bunch of GridBagLayouts for the details in those panes. When that wasn't working, I figured I would try my hand at an all out GridBagLayout. Right now my goal is to get the top group of character and location panels/cards to be displayed in their correct aspect ratio (about 4:3) and have them resize correctly (maintaining aspect ratio as best as possible) as the window is resized. What I am getting is a super small square panel for each card when the window first comes up. I want them to start in the aspect ratio (4:3) to begin with.
Am I going about this correctly?
Should I stick with all GridBagLayouts?
If not, what combinations of layouts do you see that may work?
Lastly and probably most importantly, how come they do not start out with the correct gridwidth or gridheight?
It would be nice if all the cards maintained a 4:3 or 3:4 aspect ratio when the window is near a 4:3.
public class OverPower {
public static void main(String[] args) {
JFrame table = new JFrame();
table.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
table.setLayout(new BorderLayout());
JPanel contentPane = new OppCharsPanel();
table.setContentPane(contentPane);
table.setLocationByPlatform(true);
table.pack();
table.setLocationRelativeTo(null);
table.setVisible(true);
}
}
public class OppCharsPanel extends JPanel {
public OppCharsPanel() {
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(20, 15, 20, 15);
gbc.fill = GridBagConstraints.BOTH;
gbc.gridwidth = 4;
gbc.gridheight = 3;
gbc.weightx = 4.0;
gbc.weighty = 3.0;
//back row
gbc.gridx = 4;
gbc.gridy = 0;
JPanel oppHomebase = new JPanel();
oppHomebase.setBackground(Color.RED);
this.add(oppHomebase, gbc);
gbc.gridx = 8;
gbc.gridy = 0;
JPanel oppReserve = new JPanel();
oppReserve.setBackground(Color.RED);
this.add(oppReserve, gbc);
//front row
gbc.gridx = 0;
gbc.gridy = 3;
JPanel oppBattlesite = new JPanel();
oppBattlesite.setBackground(Color.RED);
this.add(oppBattlesite, gbc);
gbc.gridx = 4;
gbc.gridy = 3;
JPanel oppChar1 = new JPanel();
oppChar1.setBackground(Color.RED);
this.add(oppChar1, gbc);
gbc.gridx = 8;
gbc.gridy = 3;
JPanel oppChar2 = new JPanel();
oppChar2.setBackground(Color.RED);
this.add(oppChar2, gbc);
gbc.gridx = 12;
gbc.gridy = 3;
JPanel oppChar3 = new JPanel();
oppChar3.setBackground(Color.RED);
this.add(oppChar3, gbc);
}
}

Start by breaking down each layout section into it's individual requirements and focus on those needs, for example...
Area #1
Okay, so basically, this has three main components (each coloured section is it's own panel), which could be used with a BorderLayout
Area #2
So here, you have another three areas/panels, because of the different requirements for vertical space, I might be tempted to use a GridBagLayout, this would allow you to define more space to the two top components then the bottom one...
Area #3
So, again three main areas. Here I'd be tempted to use a BorderLayout again. For the indivdual containers, I might use a GridBagLayout or Rob Camick's WrapLayout (for laying out the images within each of the three areas)
Scaling
Don't worry about the layout manager trying to maintain the aspect ratio, give enough information to the layout manager so that it make better choices, overriding the getPreferredSize and getMinimumSize methods of the image components and providing appropriate sizing hints. Within these image components, I would make sure that the image is scaled to the proper aspect ratio and rendered correctly

Starting GridBagLayout from top left corner in Java Swing

I'm new to Java Swing and I have been struggling to start the GridBagLayout from top left corner so that c.gridx=0 c.gridy=0 will put my object on the top left corner.
I'd appreciate if you could help me by telling what I need to do after this point:
JPanel panel = new JPanel(new GridBagLayout());
frame.add(panel);
GridBagConstraints c = new GridBagConstraints();
I know that I have to use NORTHWEST or FIRST_LINE_START constants, but I don't know how. I tried to do it this way' but it did not realize the constants.
frame.getContentPane().add(panel, BorderLayout.NORTHWEST);
Thanks for your help.

Read the section from the Swing tutorial on How to Use GridBagLayout. The secton on "weightx,weighty" states:
Unless you specify at least one non-zero value for weightx or weighty, all the components clump together in the center of their container.

You need to use your GridBagConstraints' anchor property. This should do it for you:
frame.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.NORTHWEST;
frame.add(panel, gbc);
I'm not guaranteeing that you won't have to set other properties of the constraints object to get the layout you desire. In particular, you may need to set weightx and weighty to be 1 so that the panel takes up all of the available space given to it.

For those, who use IDE (e.g. NetBeans), I finally found nice trick: if you want to add components to top and use their preferred sizes: add another empty panel with weighty = 1.0. Copied from auto-generated code (NetBeans):
gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 2;
gridBagConstraints.weighty = 1.0;
jPanelOptions.add(jPanelFiller, gridBagConstraints);

a quick and simple way:
add a blank JLabel to end of page:
// your code goes here
gbc.weightx = 1;
gbc.weighty = 1;
bg.add(new JLabel(" "), gbc); // blank JLabel

There's a workaround. You can put the GridBagLayout panel in a BorderLayout panel with BorderLayout.NORTH. Then Component in GridBagLayout panel will start from top position.
static void test4(){
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(480, 360);
JPanel borderLayoutPanel=new JPanel(new BorderLayout());
JPanel gridBagLayoutPanel = new JPanel(new GridBagLayout());
borderLayoutPanel.add(gridBagLayoutPanel, BorderLayout.NORTH);
frame.add(borderLayoutPanel);
JButton testButton=new JButton("test button");
GridBagConstraints c = new GridBagConstraints();
c.gridx=0;
c.gridy=0;
gridBagLayoutPanel.add(testButton, c);
frame.setVisible(true);
}

if you want the grid to go all the way to the top, simply set all your weighty = 0 until the last item, set it to any number greater than 0, it will effectively push the rest of the buttons to the top.
Don't forget to also increment your button's gridy value.
Otherwise it will be centered.
(the same can be done using gridx and weightx value if you arent using the c.fill = GridBagConstraints.HORIZONTAL property.)

How to set the component size with GridLayout? Is there a better way?

I am working on a larger GUI with Java and I am becoming angry on Layout Managers.
I have a "Settings-Panel" with a variable number of JComponents in it (Labels, Buttons, JSpinners, JSliders,...). I just want the following:
JLabel <-> JComponent
JLabel <-> JComponent
JLabel <-> JComponent
...
My Panel has a size of 500px, so that there is enough space for a lot of components. Unfortunately the GridLayout always stretches the size of the Components to the whole Panel, even if I set a MaximumSize for every component. It looks stupid if there are only two buttons each with a height of 250px.
I tried FlowLayout, but I cannot figure out a way to make new lines properly. I tried BoxLayout.Y_AXIS, but the Components are always centered, and Label and Component are not in the same line.
Does anybody know a good and short way with LayoutManagers to handle this properly?

An alternative to other layouts, might be to put your panel with the GridLayout, inside another panel that is a FlowLayout. That way your spacing will be intact but will not expand across the entire available space.

Don't use GridLayout for something it wasn't meant to do. It sounds to me like GridBagLayout would be a better fit for you, either that or MigLayout (though you'll have to download that first since it's not part of standard Java). Either that or combine layout managers such as BoxLayout for the lines and GridLayout to hold all the rows.
For example, using GridBagLayout:
import java.awt.*;
import javax.swing.*;
public class LayoutEg1 extends JPanel{
private static final int ROWS = 10;
public LayoutEg1() {
setLayout(new GridBagLayout());
for (int i = 0; i < ROWS; i++) {
GridBagConstraints gbc = makeGbc(0, i);
JLabel label = new JLabel("Row Label " + (i + 1));
add(label, gbc);
JPanel panel = new JPanel();
panel.add(new JCheckBox("check box"));
panel.add(new JTextField(10));
panel.add(new JButton("Button"));
panel.setBorder(BorderFactory.createEtchedBorder());
gbc = makeGbc(1, i);
add(panel, gbc);
}
}
private GridBagConstraints makeGbc(int x, int y) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = 1;
gbc.gridheight = 1;
gbc.gridx = x;
gbc.gridy = y;
gbc.weightx = x;
gbc.weighty = 1.0;
gbc.insets = new Insets(5, 5, 5, 5);
gbc.anchor = (x == 0) ? GridBagConstraints.LINE_START : GridBagConstraints.LINE_END;
gbc.fill = GridBagConstraints.HORIZONTAL;
return gbc;
}
private static void createAndShowUI() {
JFrame frame = new JFrame("Layout Eg1");
frame.getContentPane().add(new LayoutEg1());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}

For more complex layouts I often used GridBagLayout, which is more complex, but that's the price. Today, I would probably check out MiGLayout.

In my project I managed to use GridLayout and results are very stable, with no flickering and with a perfectly working vertical scrollbar.
First I created a JPanel for the settings; in my case it is a grid with a row for each parameter and two columns: left column is for labels and right column is for components. I believe your case is similar.
JPanel yourSettingsPanel = new JPanel();
yourSettingsPanel.setLayout(new GridLayout(numberOfParams, 2));
I then populate this panel by iterating on my parameters and alternating between adding a JLabel and adding a component.
for (int i = 0; i < numberOfParams; ++i) {
yourSettingsPanel.add(labels[i]);
yourSettingsPanel.add(components[i]);
}
To prevent yourSettingsPanel from extending to the entire container I first wrap it in the north region of a dummy panel, that I called northOnlyPanel.
JPanel northOnlyPanel = new JPanel();
northOnlyPanel.setLayout(new BorderLayout());
northOnlyPanel.add(yourSettingsPanel, BorderLayout.NORTH);
Finally I wrap the northOnlyPanel in a JScrollPane, which should behave nicely pretty much anywhere.
JScrollPane scroll = new JScrollPane(northOnlyPanel,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
Most likely you want to display this JScrollPane extended inside a JFrame; you can add it to a BorderLayout JFrame, in the CENTER region:
window.add(scroll, BorderLayout.CENTER);
In my case I put it on the left column of a GridLayout(1, 2) panel, and I use the right column to display contextual help for each parameter.
JTextArea help = new JTextArea();
help.setLineWrap(true);
help.setWrapStyleWord(true);
help.setEditable(false);
JPanel split = new JPanel();
split.setLayout(new GridLayout(1, 2));
split.add(scroll);
split.add(help);

You need to try one of the following:
GridBagLayout
MigLayout
SpringLayout
They offer many more features and will be easier to get what you are looking for.

I used WrapFlowLayout instead
JPanel yourPanel = new JPanel(new WrapFlowLayout(10, 10);

How the swing's BoxModel works?

Let's say I would like to create a simple calculator. It consists of 3 fields. Text field to show result, field with checkboxes to select system and field with numbers.
What kind of component should I use for each element ?
How can I position elements in my window ?
How can I position elements inside component (ie checkboxes) ?
This is what I'm trying to achieve.
http://img28.imageshack.us/img28/7691/lab8c.jpg

I would use
JTextField for the number-window
JRadioButton for the radio buttons, and
JButton for the buttons.
The layout of the components should be deferred to a so called layout-manager. (Have a look at Using Layout Managers. In this case a GridLayout and/or a GridBagLayout would do fine.
This code should get you started:
import java.awt.*;
import javax.swing.*;
public class FrameTest {
public static void main(String[] args) {
final JFrame f = new JFrame("Frame Test");
JPanel panel = new JPanel(new GridBagLayout());
panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weightx = 1.0;
panel.add(new JTextField(), gbc);
JPanel numSysPanel = new JPanel(new GridLayout(1, 3));
numSysPanel.setBorder(BorderFactory.createTitledBorder("Number System"));
numSysPanel.add(new JRadioButton("oct"));
numSysPanel.add(new JRadioButton("dec"));
numSysPanel.add(new JRadioButton("hex"));
panel.add(numSysPanel, gbc);
JPanel buttons = new JPanel(new GridLayout(4, 4, 2, 2));
for (int i = 0; i < 16; i++)
buttons.add(new JButton("" + i));
panel.add(buttons, gbc);
f.setContentPane(panel);
f.pack();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
}

First off, you start with determining, which LayoutManager you should use, to arrange your three fields. GridBagLayout will definitely do what you want, but is quite hard to program. You could try to get away with the simpler BorderLayout, which will make your application look odd, while resizing. You can use GroupLayout too. BoxLayout, GridLayout and FlowLayout are not what you want to use. Now you have a lot of options, to lay out you top elements.
Use a JTextField for the result. Use JCheckBox for the checkboxes, which you put insider a JPanel with an etched border (via JPanel.setBorder(BorderFactory.createEtchedBorder())) and a FlowLayout. Don't forget to put the checkboxes in a CheckboxGroup. Last but not least use a JPanel to group the JButtons for the, uhh, buttons. Use a GridLayout (5 rows, 4 columns) to arrange these buttons.

GridBagLayout padding

I am using a GridBagLayout to (currently) display two rows. I am aware this layout is overkill for this task, but am trying to learn how to use it. The problem is that I have added the two panels to the two separate rows and there is a huge gap around the content (see image and code below):
alt text http://www.imagechicken.com/uploads/1264533379009864500.png
Image background;
public Table(){
super();
ImageIcon ii = new ImageIcon(this.getClass().getResource("pokerTableV2.png"));
background = ii.getImage();
setSize(Constants.FRAME_WIDTH, Constants.TABLE_HEIGHT);
setLayout(new GridBagLayout());
GridBagConstraints constraints = new GridBagConstraints();
constraints.gridx = 0;
constraints.gridy = 0;
constraints.fill = GridBagConstraints.HORIZONTAL;
JButton button = new JButton("hello world");
JPanel panel1 = new JPanel();
panel1.setPreferredSize(new Dimension(800,100));
panel1.add(button, BorderLayout.CENTER);
panel1.setBackground(Color.yellow);
add(panel1, constraints);
constraints.gridx = 0;
constraints.gridy = 1;
JPanel middlePanel = new JPanel();
middlePanel.setPreferredSize(new Dimension(800,350));
middlePanel.add(button, BorderLayout.CENTER);
middlePanel.setBackground(Color.blue);
add(middlePanel, constraints);
}

Use
constraints.fill = GridBagConstraints.BOTH;
constraints.weightx = 1d;
constraints.weighty = 1d;
JavaDoc for weightx/weighty says:
Specifies how to distribute extra horizontal/vertical space.
JavaDoc for fill:
This field is used when the component's display area is larger
than the component's requested size. It determines whether to
resize the component, and if so, how.

Unfortunately, with GridBagLayout, if the contents do not fill the entire container that it is in, it will automatically center all its contents within its container. That is why you are getting a really large gap.
There are essentially two ways to fix this:
The hard way: Fiddle with the GridBagConstraints. I had limited success with this when trying to avoid the centre-ing behaviour.
The easy way: Put the GridBagLayout inside of a FlowLayout, and then set the alignment of the FlowLayout to top-left, or whatever you wish.
I have asked, and answered, this question myself sometime last week.
So in your case you are adding your panel1 and middlePanel directly to the JFrame (?), with a GridBagLayout
JFrame (GridBagLayout)
- panel1
- middlePanel
I would suggest this alternative structure instead, to get rid of all the extra space (and centre alignment as well, if you like).
JFrame (FlowLayout)
- JPanel (GridBagLayout)
- panel1
- middlePanel
HTH