Increase Table/scroll pane size corresponding to split pane

[John Jai]

Hi,
When i drag the divider from left to right, the left component is not increasing in its size and occupying the split pane. How to make it the component (jtable & scrollpane) to drag itself and go to the entire size of split pane.

sample code -

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;

public class TableInSplitPaneIssue {
	public static void main(String[] args) throws Exception {  
		SwingUtilities.invokeLater(new Runnable() {  
			public void run() {  
				new TableInSplitPaneIssue().makeUI();  
			}  
		});  
	}  

	public void makeUI() {  
		Object[][] data = {  
				{"One"},  
				{"Two"},  
				{"Three"}  
		};  
		String[] columns = {"Column 1"};  
		JTable table = new JTable(data, columns);  
		table.setSize(200,200);
		table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);  
		JScrollPane scrollPane = new JScrollPane(table);
		scrollPane.setSize(200, 200);

		JSplitPane splitPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, scrollPane, new JPanel());
		splitPane.setDividerLocation(50);
		JFrame frame = new JFrame();  
		frame.add(splitPane);  

		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
		frame.setSize(400, 400);  
		frame.setLocationRelativeTo(null);  
		frame.setVisible(true);  
	}  
}

[John Jai]

After adding a component listener for scroll pane i was able to make the change. Actually scroll pane was increasing its size when the split pane increases, it was the table that did not increase its size automatically.

I have one question - why the propertylistener that listens for divider change prints 5 times when i move the divider once?

import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTable;
import javax.swing.JViewport;
import javax.swing.SwingUtilities;

public class TableInSplitPaneIssue {
	DividerChangeListener dividerListener = new DividerChangeListener();
	ScrollPaneListener scrollListener = new ScrollPaneListener();
	public static void main(String[] args) throws Exception {  
		SwingUtilities.invokeLater(new Runnable() {  
			public void run() {  
				new TableInSplitPaneIssue().makeUI();  
			}  
		});  
	}  

	public void makeUI() {  
		Object[][] data = {  
				{"One"},  
				{"Two"},  
				{"Three"}  
		};  
		String[] columns = {"Column 1"};  
		JTable table = new JTable(data, columns);  
		table.setSize(200,200);
		table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);  
		JScrollPane scrollPane = new JScrollPane(table);
		scrollPane.setSize(200, 200);
		scrollPane.addComponentListener(scrollListener);
		

		JSplitPane splitPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, scrollPane, new JPanel());
		
		splitPane.addPropertyChangeListener(dividerListener);
		splitPane.setDividerLocation(50);
		JFrame frame = new JFrame();  
		frame.add(splitPane);  

		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
		frame.setSize(400, 400);  
		frame.setLocationRelativeTo(null);  
		frame.setVisible(true);  
	}  
	
	class DividerChangeListener implements PropertyChangeListener{
		public void propertyChange(PropertyChangeEvent evt) {
			JSplitPane sourceSplitPane = (JSplitPane)evt.getSource();
			JScrollPane scrollPane = (JScrollPane)sourceSplitPane.getLeftComponent();
			System.out.println("Scroll Pane Divider Changed!!!");
		}		
	}
	
	class ScrollPaneListener extends ComponentAdapter{		
		public void componentResized(ComponentEvent e) {
			JScrollPane scrollPane = (JScrollPane)e.getSource();
			JTable table = (JTable)(((JViewport)scrollPane.getComponent(0)).getView());
//			System.out.println("Now table size -> " + table.getWidth());
			table.setSize(scrollPane.getSize());
//			System.out.println("Now table size after modifiying-> " + table.getWidth());
			table.getColumnModel().getColumn(0).setPreferredWidth(table.getWidth());
		}		
	}
}

[Ranganathan Kaliyur Mannar]

The scrollpane and component do occupy the entire left area when you drag the splitpane. However, as the column size the table is smaller, it gives you a illusion that it doesn't occupy the space. Do the following:
1) Drag the divider.
2) Then resize the column i.e increase the column size by dragging the header. You would see the horizontal scroll bar appear - which will show you that the scrollpane does occupy the entire space.

[John Jai]

Yes, the column width was the one needed to be increased. But i took some time to figure out how to increase it - finally i have to set the min width, max width and then preferred width to actually increase the column width