This method has to return the composite, where components (i.e. Pages) are to be embedded. e.g.:

getClientComposite(){
    return clientCompW;
}

This method has to return the java.util.ResourceBundle containing the labels for all menu items. e.g.:

getMenuResource() {
    Locale locale = getComponent().getContext().getLocale();
    ResourceBundle labels = ResourceBundle.getBundle("at.spardat.demoshell.client.menu",locale);
    return labels;
}

This method has to create the root task of the application. The root task will be called immediately after the window of the AppShell is opened and takes over the job of creating the main menu (by adding MenuItem s). e.g.:

createRootTask(){
   return new MyRootTask(this);
}

An root task example can be seen in: Root Task

This method has to return the SWT-Composite where the base class can attach a list containing the context strings of all tasks and components on the call stack. This list will fill the composite completely and will be accessible via the protected member variable contextW. e.g.:

getContextComp(){
    return contextCompW;
{

This method has to return the SWT-Composite where the base class can attach a tree containing the menu items. This tree will fill the composite completely. The tree will be accessible via the protected member variable menuW. e.g.:

getMenuComp(){
    return menuCompW;
{

This method is already implemented in the MenuAppShell . In the MenuAppShell's implementation a menu of the style SWT.BAR at the Shell's top is created (the "classic" Windows menu). This method can be overwritten if some other kind of menu should be used as root menu for the MenuItems (like a pop-up menu). The SWT menu will be accessible via the protected member variable menuW. An example of a implementation with a pop-up menu as root:

protected Menu getMenu(){
     Menu menu = new Menu(aComposite,SWT.POP_UP);
     aComposite.setMenu(menu);
     return menu;
}

When constructing an SWT menu by using the MenuAppShell and XMA MenuItems the style information has to be set in the constructor and is prolonged to the underlying SWT MenuItem. The following styles are valid for SWT MenuItems:

Otherwise a RuntimeException would be thrown. And of course it makes no sense to attach a Task to a MenuItem of the style SWT.CASCADE or SWT.SEPARATOR as this Task could never be chosen. If no style is set then the MenuItem behaves like an item with an SWT.PUSH style, but this behaviour is nether documented nor guaranteed by SWT. A programmer constructing an SWT Menu by using XMA MenuItems has not to regard that a SWT MenuItem always needs a SWT Menu as parent. The needed SWT Menus are generated by the XMA framework, so child items can be directly added to MenuItems of the style SWT.CASCADE.

Usually the style information for the XMA MenuItem can be omitted. SWT does not document any special styles for TreeItems.

To implement a Task you create a class derived from Task . You have to implement the abstract method run(). This method is called when the Task is called. It can be invoked more than once on the same instance. After this method is completed, control returns to the caller.

The protected member field app contains the application shell this task is running in. The protected member field menu contains the parent MenuItem of the Task.

    MySubTask subtask = new MySubTask(getComponent());
    subtask.setIdClient(idClient);
    menu.addItem(new MenuItem("MySubTask", subtask));    

    EmbeddableComponent comp = (EmbeddableComponent) getComponent().getSession().getComponent("MySubTask");
    comp.setIdClient(idClient);
    callBlocking(comp);    

    EmbeddableComponent comp = (EmbeddableComponent) getComponent().getSession().getComponent("MySubTask");
    comp.setIdClient(idClient);
    callNonBlocking(comp);

    EmbeddableComponent comp = (EmbeddableComponent) getComponent().getSession().getComponent("MySubTask");
    comp.setIdClient(idClient);
    comp.invoke(app.getShell);
    comp.dispose();

    MySubTask subtask = new MySubTask(getComponent());
    subtask.setIdClient(idClient);
    call(subtask);

If you want to call a task, you have to use the method call() of the Task on top of the call stack. You get this Task by calling getTopTask() on the application shell. If you call from a page embedded directly or indirectly in the main application page you get the application shell by calling getDialog(). If you call from a page invoked as dialog, you have to maintain a variable pointing to the application shell yourself.

    MySubTask subtask = new MySubTask(getComponent());
    subtask.setIdClient(idClient);
    ((IAppShell)getDialog()).getTopTask().call(subtask);

After a task object is created, it is not fully initialized. It depends on which constructor was used, which protected member variables are defined, and which are undefined.

When the task is started, it is attached to its parent task and therefore to the task stack of the AppShell. Now all of its member variables get fully initialized, it enters its active state and its run() -method is called at last.

The task stays active and attached to its parent task and the task stack until its method closeRequested() is called. In this method it removes the component or page it embeds in the AppShell and detaches from its parent task and the task stack. It becomes inactive and most of its member variables become null.

closeRequested() is called automatically from the runtime when another menu item is selected. If the task only uses callBlocking() you should call closeRequested() at the end of your run() -method to close the task.

An AppShell s Root Task is a Task returned by the AppShell's method createRootTask(). Usually the implementation of this method contains only of: return new MyRootTask(this).

In the Root Task's run() -method is the code that builds the menu - by using XMA MenuItems - and attaches Tasks to items. An example:

    public void run() {

        menu.addItem(new MenuItem("search",new Task(getComponent()) {
            public void run() {
                IComponentClient comp = getComponent().getSession().getComponentExtern("http://localhost:8080/xma_samplespar/Kundensuche");
                callBlocking((IXMAControl)comp);
            }
        }));

        MenuItem sparen = new MenuItem("sparen",SWT.CASCADE);
        menu.addItem(sparen);

        sparen.addItem(new MenuItem("sparen_search",new Task(getComponent(),SWT.PUSH,someImage) {
            public void run() {
                IComponentClient comp = getComponent().getSession().getComponent("SparenSearch");
                callNonBlocking((IXMAControl)comp);
            }
        }));

        sparen.addItem(new MenuItem("sparen_umsatz",new Task(getComponent(),SWT.PUSH) {
            public void run() {
                IComponentClient comp = getComponent().getSession().getComponent("SparenUmsatz");
                callBlocking((IXMAControl)comp);
            }
        }));
    }