how to dynamically add swt widgets to a composite?

Question

I\'m trying to add widgets like text boxes, buttons to a composite on click of a button. I\'ve tried , but i could only add these widgets dynamically only up to the size of

Answer 1

The solution to your problem is to set the minimum size of the ScrolledComposite each time you add/remove a widget. You will use setMinSize(Point) API from ScrolledComposite. Also, remember to layout() the scrolled composite, and not its children. The laying of children will be done automatically.

The add button currently moves along with each newly added component. If you want it to not move, just move it outside the scrolled composite content.

Also, I've cleaned up your code a little bit, I hope you don't mind. :-)

public class DynamicDialog extends Dialog 
{
    private int count = 1;

    public DynamicDialog(final Shell parent) 
    {
        super(parent);
    }

    @Override
    protected Control createDialogArea(final Composite parent) 
    {
        final Composite container = (Composite) super.createDialogArea(parent);
        container.setLayout(new FillLayout());

        final ScrolledComposite scrolledComposite = new ScrolledComposite(container, SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL);
        scrolledComposite.setExpandHorizontal(true);
        scrolledComposite.setExpandVertical(true);

        final Composite composite = new Composite(scrolledComposite, SWT.NONE);
        composite.setLayout(new GridLayout(1, false));
        scrolledComposite.setContent(composite);
        scrolledComposite.setSize(composite.computeSize(SWT.DEFAULT, SWT.DEFAULT));

        final Composite composite_1 = new Composite(composite, SWT.NONE);
        composite_1.setLayout(new GridLayout(2, false));
        composite_1.setLayoutData(new GridData(SWT.LEFT, SWT.CENTER, false, false));

        final Label lblDefault = new Label(composite_1, SWT.NONE);
        lblDefault.setLayoutData(new GridData(SWT.RIGHT, SWT.CENTER, false, false, 1, 1));
        lblDefault.setText("Default:");

        final Combo combo = new Combo(composite_1, SWT.NONE);
        combo.setLayoutData(new GridData(SWT.LEFT, SWT.CENTER, true, false, 1, 1));

        final Composite composite_2 = new Composite(composite, SWT.NONE);
        composite_2.setLayout(new GridLayout(4, false));
        composite_2.setLayoutData(new GridData(SWT.LEFT, SWT.CENTER, false, false));

        final Composite composite_3 = new Composite(composite, SWT.NONE);
        composite_3.setLayout(new GridLayout());
        composite_3.setLayoutData(new GridData(SWT.LEFT, SWT.CENTER, false, false));

        final Button btnAdd = new Button(composite_3, SWT.NONE);
        btnAdd.setText("Add");
        btnAdd.addSelectionListener(new SelectionAdapter() 
        {
            @Override public void widgetSelected(final SelectionEvent e) 
            {
                final Label label2 = new Label(composite_2, SWT.NONE);
                label2.setLayoutData(new GridData(SWT.RIGHT, SWT.CENTER, false, false, 1, 1));
                label2.setText( String.valueOf(count++) );

                new Text(composite_2, SWT.BORDER).setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, false));
                new Text(composite_2, SWT.BORDER).setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, false));
                new Button(composite_2, SWT.NONE).setText("Delete");

                // DO THIS:
                scrolledComposite.layout(true, true);
                scrolledComposite.setMinSize(composite.computeSize(SWT.DEFAULT, SWT.DEFAULT));
                // .. and it will work
            }
        });

        return container;
    }

    @Override
    protected void createButtonsForButtonBar(final Composite parent) 
    {
        createButton(parent, IDialogConstants.OK_ID, IDialogConstants.OK_LABEL, true);
        createButton(parent, IDialogConstants.CANCEL_ID, IDialogConstants.CANCEL_LABEL, false);
    }

    /**
     * Return the initial size of the dialog.
     */
    @Override
    protected Point getInitialSize() 
    {
        return new Point(450, 300);
    }

    public static void main(final String[] args)
    {
        final Shell shell = new Shell(new Display());
        shell.setLayout(new FillLayout());

        new DynamicDialog(shell).open();
    }
}