GridBagLayout resize issue

[David Miranda]

Hello,

Im trying to left-orient a JLabel and JList in a GridBagLayout panel thats in a split pane.

I'm using a GridBagLayout because I'm trying to left orient everything in the panel...I tried to use a BoxLayout but everything was center-oriented, the only way I found to get the Label to become left-oriented in the pane was to increase the size of the label to size of the surrounding pane (I dont want to hard code the size of the label )

I want the the GridBagLayout panel to resize correctly when the split pane is pulled up and down....but when I move the drag the split pane up towards the list, the JList gets crushed...not shrunk like expect...crushed and center-oriented in the panel

Please tell me what I'm doing wrong!

Also, if anybody can tell me how to left-orient components in the surrounding pane without using a GridBagLayout or hard-coding the component size, that'd be great.

Thanks,

David

Here's my code:

 
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
 
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
 
public class SwingTest3 {

public static void main(String[] args) {
JFrame frame = new JFrame();

frame.setSize(new Dimension(450,300));
frame.setLayout(new BorderLayout());

frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});

JSplitPane splitPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,getLeftPanel(),getRightPanel());

frame.getContentPane().add(splitPane);

frame.pack();
frame.setVisible(true);

}

private static Component getLeftPanel() {

JSplitPane leftPane = getSplitPane();

return leftPane;
}

private static JSplitPane getSplitPane() {

JPanel panel1 = new JPanel();

//trying gridbaglayout in effort to left orient the labels without explicitly setting size or alignment
panel1.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();

c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
//c.anchor = GridBagConstraints.FIRST_LINE_START;


//panel1.setLayout(new BoxLayout(panel1,1));
JLabel label1 = new JLabel("Pane 1 Label");

panel1.add(label1,c);

c.weightx = 1.0f;
c.weighty = 1.0f;
c.gridy = 1;

Component list = getList();
 
panel1.add(list,c);

JPanel panel2 = new JPanel();

JLabel label2 = new JLabel("Pane 2 Label");

panel2.add(label2);

//panel2.setMinimumSize(new Dimension(100,100));

JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT,panel1,panel2);

//splitPane.setMinimumSize(new Dimension(100,100));

return splitPane;
}

private static Component getList() {

String[] items = new String[] {"This is item1","This is item 2","This is item 3","This is item 4"};

JList list = new JList(items);

JScrollPane pane = new JScrollPane(list);

return pane;
}
 
private static Component getRightPanel() {

JPanel rightPanel = new JPanel();
rightPanel.setLayout(new BorderLayout());
 
JPanel controlPanel = new JPanel();

controlPanel.setPreferredSize(new Dimension(300,300));
controlPanel.setLayout(new FlowLayout());
 
rightPanel.add(controlPanel);

return rightPanel;
}
}
 
 
    

[ June 30, 2007: Message edited by: David Miranda ]
[ July 01, 2007: Message edited by: David Miranda ]

[Michael Dunn]

    
  private static JSplitPane getSplitPane() {
    JPanel panel1 = new JPanel();
    panel1.setLayout(new BoxLayout(panel1,BoxLayout.Y_AXIS));
    JLabel label1 = new JLabel("Pane 1 Label");
    panel1.add(label1);
    Component list = getList();
    panel1.add(list);
    JPanel panel2 = new JPanel();
    JLabel label2 = new JLabel("Pane 2 Label");
    panel2.add(label2);
    JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT,panel1,panel2);
    return splitPane;
  }
  private static Component getList() {
    String[] items = new String[] {"This is item1","This is item 2","This is item 3","This is item 4"};
    JList list = new JList(items);
    JScrollPane pane = new JScrollPane(list);
    pane.setAlignmentX(0.0f);//<-----------------------------------------
    return pane;
  }

[David Miranda]

Thanks Mike

Does anyone know why the GridBagLayout code crushed the contents when the panel resize made it smaller?

Thanks
[ July 01, 2007: Message edited by: David Miranda ]

[David Miranda]

EUREKA!

Well, the fix was remarkably easy.

Turns out that I needed to set the constraints fill to GridBagConstraints.BOTH for the component that I want to fill the remainder of both the horizontal and vertical space.

Here's the code for those who may come after with this problem (I've seen at least a half-dozen before me using search)

 
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
 
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
 
public class SwingTest3 {

public static void main(String[] args) {
JFrame frame = new JFrame();

frame.setSize(new Dimension(450,300));
frame.setLayout(new BorderLayout());

frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});

JSplitPane splitPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,getLeftPanel(),getRightPanel());

frame.getContentPane().add(splitPane);

frame.pack();
frame.setVisible(true);

}

private static Component getLeftPanel() {

JSplitPane leftPane = getSplitPane();

return leftPane;
}

private static JSplitPane getSplitPane() {

JPanel panel1 = new JPanel();

//trying gridbaglayout in effort to left orient the labels without explicitly setting size or alignment
panel1.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();

c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
 
JLabel label1 = new JLabel("Pane 1 Label");

panel1.add(label1,c);

c.fill = GridBagConstraints.BOTH;//<---- New
c.weightx = 1.0f;
c.weighty = 1.0f;
c.gridy = 1;

Component list = getList();
 
panel1.add(list,c);

JPanel panel2 = new JPanel();

JLabel label2 = new JLabel("Pane 2 Label");

panel2.add(label2);
 
JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT,panel1,panel2);

return splitPane;
}

private static Component getList() {

String[] items = new String[] {"This is item1","This is item 2","This is item 3","This is item 4"};

JList list = new JList(items);

JScrollPane pane = new JScrollPane(list);

return pane;
}
 
private static Component getRightPanel() {

JPanel rightPanel = new JPanel();
rightPanel.setLayout(new BorderLayout());
 
JPanel controlPanel = new JPanel();

controlPanel.setPreferredSize(new Dimension(300,300));
controlPanel.setLayout(new FlowLayout());
 
rightPanel.add(controlPanel);

return rightPanel;
}
}
 
    

[ July 01, 2007: Message edited by: David Miranda ]