Familiar components in every UI framework, dialog boxes and menus are used by almost all applications. Mojo’s Dialog and Menu widgets provide the expected features, but have some unique additions. With custom dialogs, you can include any web content in a dialog box. Additionally, you can customize menus by scene and present them as either conventional drop-down lists or floating elements.
Dialogs and menus are both fundamental widgets, though more complex
than the basic widgets covered in Chapter 3, and they are
accessed and managed differently than other widgets. Dialogs are
instantiated through controller functions rather than through setupWidget, and showDialog requires an assistant as one of its
components.
Menus are instantiated by setupWidget, but use the Commander
Chain to propagate menu commands between stage assistants and
scene assistants. The Commander Chain is a model for propagating commands
through the application, stage, and scene controllers, and is described in
detail near the end of this chapter.
As in Chapter 3, we’ll explore these widgets in the context of adding them into the News application. This will be accompanied by a general description and some screenshots.
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