A window is a rectangular area of the screen in which graphical controls are displayed, and which receives the user's actions on the keyboard or mouse. Currently, applications can be developed using three classes of window:
A dialog box is a window that is often called in an inhibiting manner, to let the user read or input information. Dialog boxes can, however, have a menu bar and be used as an application's main window. When a dialog box is called non-modally, it is displayed constantly in front of the main window, provided its layout was created after the main window. If not, it can be concealed by the main window.
A main window generally contains the program's title bar, a menu bar, a frame, one or more tool bars and a status bar. This type of window contains a client area in which child windows are displayed.
Note: This type of window is not supported by the Java generator.
A child window is one displayed in truncated form in the main window's client area. Its execution is always non-inhibiting. This means that several child windows can be open simultaneously, but only one will be active at any given time. Child windows can have a menu bar, which replaces the main window's menu bar when activated.
They can be minimized and shown in the bottom left of the client area, or maximized to occupy the entire client area, in which case, the title bar disappears, and the title supplements the main window's title.
Child windows can be displayed in either cascade or tiled format. Their icons can be rearranged using the main window's methods.
Note: This type of window is not supported by the Java generator.
During the layout design process, you can place any type of graphical object in the background of a child window or dialog box. However, only the tool bar can be placed on the background of a main window.
The layout for a child window must be designed after the main window, which can be in either the same program or a calling program.
A child window cannot be executed unless a main window has already been executed. If a main window and a child window must be executed when an application is run, the EXECUTE instruction for the child window must be triggered by the main window's Initialization event.
Applications generally only have one main window. However, several main windows can be defined in the same ADELIA program or the same application. A button is created in the system task bar for each main window.
When a program is called, all the windows are created immediately, in the order represented by the program's tree view in the editor. When a child window is created, the identity of the parent window must be known. The parent window can be either the most recently-created main window or the main window most recently activated by the user. This means that it is possible to write a program that contains only child windows, provided the program is called from a program containing a main window.
Daughter windows and main windows can have shared menu options. These options can be coded just once in the main window, by entering the same option name when defining the menus.
Daughter windows and dialog boxes can use tabs; graphical controls can be placed on different pages or in the margins. Only one page is visible at any given time.
Note:
A program that executes a window will only terminate if its own windows and any other windows that are executed modally or otherwise (by the program itself or by other programs in the same process) after its window is executed have been closed.
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the properties,
the events.
the methods.