SWT Composite not visible on window maximizing

Question

Working on a SWT Jface Java Project at windowbuilder in Neon Eclipse. Have 2 Composites on a shell which are set visible for an event handler.

package br.engenharia.investimentos;

import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.custom.StackLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.MenuItem;
import org.eclipse.swt.widgets.Group;
import org.eclipse.wb.swt.SWTResourceManager;
import org.eclipse.swt.layout.FormLayout;
import org.eclipse.swt.widgets.Text;
import org.eclipse.swt.layout.FormData;
import org.eclipse.swt.layout.FormAttachment;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.layout.RowLayout;
import org.eclipse.swt.layout.RowData;
import org.eclipse.swt.layout.GridData;

public class Investimentos {

    protected Shell shellSistemaInvestimentos;
    private Text txtCompra;

    /**
     * Launch the application.
     * @param args
     */
    public static void main(String[] args) {
        try {
            Investimentos window = new Investimentos();
            window.open();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Open the window.
     */
    public void open() {
        Display display = Display.getDefault();
        createContents();
        shellSistemaInvestimentos.open();
        shellSistemaInvestimentos.layout();
        while (!shellSistemaInvestimentos.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
    }

    /**
     * Create contents of the window.
     */
    protected void createContents() {
        shellSistemaInvestimentos = new Shell();
        shellSistemaInvestimentos.setSize(450, 300);
        shellSistemaInvestimentos.setText("Sistema Investimentos");
        shellSistemaInvestimentos.setLayout(new StackLayout());

        Composite compositeAcoesCompra = new Composite(shellSistemaInvestimentos, SWT.NONE);
        compositeAcoesCompra.setFont(SWTResourceManager.getFont("Segoe UI", 16, SWT.BOLD));
        compositeAcoesCompra.setLayout(new FormLayout());

        txtCompra = new Text(compositeAcoesCompra, SWT.BORDER | SWT.WRAP | SWT.CENTER);
        FormData fd_txtCompra = new FormData();
        fd_txtCompra.top = new FormAttachment(0, 5);
        fd_txtCompra.left = new FormAttachment(0);
        fd_txtCompra.right = new FormAttachment(100);
        txtCompra.setLayoutData(fd_txtCompra);
        txtCompra.setBackground(SWTResourceManager.getColor(SWT.COLOR_WIDGET_BACKGROUND));
        txtCompra.setFont(SWTResourceManager.getFont("Segoe UI", 16, SWT.BOLD));
        txtCompra.setForeground(SWTResourceManager.getColor(SWT.COLOR_DARK_RED));
        txtCompra.setText("A\u00E7\u00F5es - Compra");

        Composite compositeAcoesOperacao = new Composite(shellSistemaInvestimentos, SWT.NONE);

        Composite compositeAcoesResultado = new Composite(shellSistemaInvestimentos, SWT.NONE);

        Composite compositeAcoesEvento = new Composite(shellSistemaInvestimentos, SWT.NONE);

        Menu menuPrincipalBar = new Menu(shellSistemaInvestimentos, SWT.BAR);
        shellSistemaInvestimentos.setMenuBar(menuPrincipalBar);

        MenuItem mntmAcoesSubmenu = new MenuItem(menuPrincipalBar, SWT.CASCADE);
        mntmAcoesSubmenu.setText("A\u00E7\u00F5es");

        Menu menuAcoesCascade = new Menu(mntmAcoesSubmenu);
        mntmAcoesSubmenu.setMenu(menuAcoesCascade);

        //Set compositeAcoesCompra visible. After I'll make the same for others.
        MenuItem mntmCompraItem = new MenuItem(menuAcoesCascade, SWT.NONE);
        mntmCompraItem.addSelectionListener(new SelectionAdapter() {
            @Override
            public void widgetSelected(SelectionEvent e) {
                compositeAcoesCompra.setVisible(true);
                compositeAcoesOperacao.setVisible(false);
                compositeAcoesResultado.setVisible(false);
                compositeAcoesEvento.setVisible(false);
            }
        });
        mntmCompraItem.setText("Compra");

        MenuItem mntmOperacaoItem = new MenuItem(menuAcoesCascade, SWT.NONE);
        mntmOperacaoItem.setText("Opera\u00E7\u00E3o");

        MenuItem mntmResultadoItem = new MenuItem(menuAcoesCascade, SWT.NONE);
        mntmResultadoItem.setText("Resultado");

        MenuItem mntmEventoItem = new MenuItem(menuAcoesCascade, SWT.NONE);
        mntmEventoItem.setText("Evento");

    }
}

The Composite is made visible by the event handler, but while window is maximized Composite is not visible anymore, except event handler is set again.

What to do in order to have Composite visible on window maximizing?

greg-449 greg-449 · Accepted Answer · 2016-10-06T14:25:54

You have specified StackLayout as the layout for the shell. This expects to show exactly one child control at a time and you must set the topControl field to be the control you want to show.

So you need to do something like:

StackLayout layout = new StackLayout();
shellSistemaInvestimentos.setLayout(layout);

...

layout.topControl = compositeAcoesCompra; // whichever control you want to show

Do not call setVisible on any of the composites as this will confuse StackLayout.

SWT Composite not visible on window maximizing

1 Answers