SWT: GridLayout column span - layout

Question

I've been using SWT for a few years, but i can't seem to figure this one out:
I need to SPLIT a VIEW into 2 "zones": LEFT and RIGHT
So i use a Composite with GridLayout with 2 columns to do it.
Inside the RIGHT composite i have a FIXED number of columns (created inside another GridLayout composite) but inside the LEFT composite i need to create a DYNAMIC number of columns that spans on the composite limit...
Is there a way to achieve this?
I tried a RowLayout inside left composite, but these 2 don't match :-\
Thanks

Answer 1

As it is not clear what you mean by
columns that spans on the composite limit
I tried a RowLayout inside left composite, but these 2 don't match
Therefore I am assuming that you want a dynamically changing gridlayout for your left composite. See the code below, specially the button.addSelectionListener().
import java.util.Random;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;
public class DynamicComposite
{
public static void main(String[] args) {
new DynamicComposite().start();
}
private Composite compositeLeft;
private Composite compositeRight;
private Random rand;
public void start()
{
rand = new Random(System.currentTimeMillis());
Display display = new Display();
Shell shell = new Shell(display);
shell.setLayout(new GridLayout(2, true));
shell.setText("Dynamic Columns");
createRightComposite(shell);
createLeftComposite(shell);
createButtonComposite(shell);
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
display.dispose();
}
private void createButtonComposite(Shell shell)
{
Label l = new Label(shell, SWT.SEPARATOR|SWT.HORIZONTAL);
GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, false);
gridData.horizontalSpan = 2;
l.setLayoutData(gridData);
Button button = new Button(shell, SWT.PUSH);
gridData = new GridData(SWT.CENTER, SWT.CENTER, true, false);
gridData.horizontalSpan = 2;
button.setLayoutData(gridData);
button.setText("Change Columns !!");
button.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
if(compositeLeft == null || compositeLeft.isDisposed())
return;
GridLayout layout = (GridLayout)compositeLeft.getLayout();
int col = rand.nextInt(7);
if(col == 0)
col = 1;
layout.numColumns = col;
//compositeLeft.setLayout(layout);
compositeLeft.layout(); // You need to re-layout your composite
}
});
}
private void createRightComposite(Shell shell)
{
compositeLeft = new Composite(shell, SWT.NONE);
GridLayout gridLayout = new GridLayout(3, true);
gridLayout.marginWidth = 0;
gridLayout.marginHeight = 0;
gridLayout.marginLeft = 0;
gridLayout.marginRight= 0;
gridLayout.marginTop = 0;
gridLayout.marginBottom = 0;
gridLayout.horizontalSpacing = 0;
gridLayout.verticalSpacing = 0;
gridLayout.horizontalSpacing = 0;
compositeLeft.setLayout(gridLayout);
GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
compositeLeft.setLayoutData(gridData);
int counter = 17;
for(int i=0; i<counter; i++)
{
Button button = new Button(compositeLeft, SWT.PUSH);
button.setText("Button " + (i+1));
GridData bData = new GridData(SWT.FILL, SWT.FILL, true, false);
button.setLayoutData(bData);
}
}
private void createLeftComposite(Shell shell)
{
compositeRight = new Composite(shell, SWT.NONE);
GridLayout gridLayout = new GridLayout(3, true);
gridLayout.marginWidth = 0;
gridLayout.marginHeight = 0;
gridLayout.marginLeft = 0;
gridLayout.marginRight= 0;
gridLayout.marginTop = 0;
gridLayout.marginBottom = 0;
gridLayout.horizontalSpacing = 0;
compositeRight.setLayout(gridLayout);
GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
compositeRight.setLayoutData(gridData);
int counter = 7;
for(int i=0; i<counter; i++)
{
Button button = new Button(compositeRight, SWT.PUSH);
button.setText("Button " + (i+1));
GridData bData = new GridData(SWT.FILL, SWT.FILL, true, false);
button.setLayoutData(bData);
}
}
}