SWT - GridData and buttons

Question

I have a method to create 2 buttons. These buttons are different than the OK, Close buttons. They will perform different actions when clicked. I want the 2 buttons side by side and at the top of my base composite. Which is using GridLayout. I want to be able to place the buttons side by side.

Here is my createDialogArea that I am adding the method to.

  protected Control createDialogArea(Composite parent) {
  final Composite area = new Composite(parent, SWT.NONE);
  final GridLayout gridLayout = new GridLayout();
  gridLayout.marginWidth = 15;
  gridLayout.marginHeight = 10;
  area.setLayout(gridLayout);
  createTopButtons(area);
  createTableViewer(area);
  return area;
}

Here is the button method.

 protected void createTopButtons(Composite parent) {
   Button pdfButton = new Button(parent, SWT.PUSH);
   pdfButton.setText("Create PDF");
   pdfButton.addSelectionListener(new SelectionAdapter() {
     public void widgetSelected(SelectionEvent e) {
        close();
     }
   }); 

   Button plotButton = new Button(parent, SWT.PUSH);
   plotButton.setText("Plot");
   plotButton.addSelectionListener(new SelectionAdapter() {
     public void widgetSelected(SelectionEvent e) {
        close();
     }
   });  
 }

Would I need to add a Gridlayout to createTopButtons?
If so how would I get them side by side and not one on top of the other.

Also in the createDialogArea, can I arrange my components using the gridLayout?

Example - I want createTopButtons to be on the top left hand side, then I want createTableViewer centered

Do you arrange your items/buttons/labels using a layout inside the composite you are creating like createTopButtons. Then use a layout in the createDialogArea to arrange the composite created by the methods?

Answer 1

Q & A

Would I need to add a Gridlayout to createTopButtons?

No you need to put your buttons in another composite and this child composite should have a gridlayout with two columns.

Also in the createDialogArea, can I arrange my components using the gridLayout? Example - I want createTopButtons to be on the top left hand side, then I want createTableViewer centered

Sure, why not. But you will also need something called GridData and set it like area.setLayoutData(gridData);. For centering something, your griddata may look like this gridData = new GridData(SWT.CENTER, SWT.CENTER, true, false);

Do you arrange your items/buttons/labels using a layout inside the composite you are creating like createTopButtons. Then use a layout in the createDialogArea to arrange the composite created by the methods?

Yes. Though I dint get the second half composite created by the methods

Code

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.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;

public class SideBySide {
    public static void main(String[] args) {
        new SideBySide().start();
    }

    private Shell shell;

    public void start()
    {
        Display display = new Display();
        shell = new Shell(display);
        shell.setLayout(new GridLayout(1, true));

        GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
        shell.setLayoutData(gridData);

        shell.setText("Side By Side");

        createDialogArea(shell);

        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }

    protected Control createDialogArea(Composite parent) 
    {
        final Composite area = new Composite(parent, SWT.NONE);
        final GridLayout gridLayout = new GridLayout();
        gridLayout.marginWidth = 15;
        gridLayout.marginHeight = 10;
        area.setLayout(gridLayout);

        GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
        shell.setLayoutData(gridData);
        area.setLayoutData(gridData);

        createTopButtons(area);
        createTableViewer(area);
        return area;
    }

    private void createTableViewer(Composite area)
    {
        Table table = new Table(area, SWT.BORDER|SWT.V_SCROLL|SWT.FULL_SELECTION);
        GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
        table.setLayoutData(gridData);

        table.setLinesVisible(true);
        table.setHeaderVisible(true);

        TableColumn column = new TableColumn(table, SWT.LEFT);
        column.setWidth(320);
        column.setText("Column 1");

        column = new TableColumn(table, SWT.LEFT);
        column.setWidth(320);
        column.setText("Column 2");
    }

    protected void createTopButtons(Composite parent) 
    {

        Composite composite = new Composite(parent, SWT.NONE);
        GridLayout gridLayout = new GridLayout(2, false);
        gridLayout.marginWidth = 0;
        gridLayout.marginHeight = 0;
        gridLayout.verticalSpacing = 0;
        gridLayout.horizontalSpacing = 0;
        composite.setLayout(gridLayout);

        GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, false);
        composite.setLayoutData(gridData);

        gridData = new GridData(SWT.DEFAULT, SWT.FILL, false, false);

        Button pdfButton = new Button(composite, SWT.PUSH);
        pdfButton.setText("Create PDF");
        pdfButton.addSelectionListener(new SelectionAdapter() {
            public void widgetSelected(SelectionEvent e) {
                shell.close();
            }
        }); 

        pdfButton.setLayoutData(gridData);

        Button plotButton = new Button(composite, SWT.PUSH);
        plotButton.setText("Plot");
        plotButton.addSelectionListener(new SelectionAdapter() {
            public void widgetSelected(SelectionEvent e) {
                shell.close();
            }
        });  
        plotButton.setLayoutData(gridData);
    }
}

Code Output

Further Reading

This is a great article to understand layouts in SWT.