Implementing the close action

The close action is a predefined action dedicated to close graphical windows (for example, with the X cross button).

Purpose of the close action

With GDC/UR on desktop, the "close" action can be triggered by pressing Alt+F4 or by clicking the X cross button in the upper-right corner of the desktop window.

Figure: Window close button on desktop

Window close button on desktop

With GBC in a web browser, an X button is displayed on the right of the chromebar, to trigger the "close" action:

Figure: Chromebar close button in web browser

Chromebar close button in web browser

Genero BDL has a predefined "close" action name dedicated to this specific window closing event.

When the end user triggers an X close button, the event can be managed in the program code with an ON ACTION close block. If this action handler is not defined in the current dialog, the VM implements a default behavior for the close action, depending on the type of dialog.

The "close" action can be disabled with DIALOG.setActionActive("close",FALSE). With GDC/UR desktop, a click on the x-cross button of the desktop window will have no effect. If the chromebar is visible, the action views for the "close" action is made invisible, while the default action view button in the action panel is disabled, if present.

Details for the default action view hanlding of the "close" action:

  • With GBC in browser:

    • When the chromebar is visible, DEFAULTVIEW has no impact on the (X) close button on the right of the chromebar.

    • When the chromebar is hidden, DEFAULTVIEW is taken into account to hide or show the default action view button in the action panel.

  • With GDC/UR desktop:

    • Independently from the chromebar visiblility, the button in the action panel will never be shown: We consider the [x] button of the desktop window as the view for the "close" action, even if DEFAULTVIEW=YES?

The close action in a DIALOG multiple dialog block

The close action executes an ON ACTION close block, if defined. Otherwise, the close action is mapped to the cancel action, when an ON ACTION cancel handler is defined.

If neither ON ACTION close, nor ON ACTION cancel are defined, nothing will happen if the user tries to close the window with the X cross button or an ALT+F4 keystroke.

The int_flag register will not be set in the context of DIALOG.

The close action in singular data handling dialogs

By default, for INPUT, INPUT ARRAY, CONSTRUCT, DISPLAY ARRAY or PROMPT dialogs, the VM will create a close action, except if the singular dialog is defined with ATTRIBUTES(CANCEL=FALSE).

When an ON ACTION close handler is explicitly defined in an INPUT, INPUT ARRAY, CONSTRUCT, DISPLAY ARRAY or PROMPT dialog, the handler code will be executed if the close action is fired.

If no explicit ON ACTION close handler is defined, the close action acts the same as the cancel predefined action: When the user clicks the X cross button, the dialog stops and the int_flag is set to 1.

If there is an explicit ON ACTION cancel block defined, int_flag is set to 1 and the user code under ON ACTION cancel will be executed.

If the CANCEL=FALSE option is set, no cancel and no close action will be created, and you must write an ON ACTION close handler to proceed with the close action. In this case, the int_flag register will not be set when the close action is invoked.

The close action in MENU dialogs

By default, for the MENU dialog, the VM will create a close action, if an COMMAND KEY(INTERRUPT) or ON ACTION cancel block is defined by the MENU.

When an ON ACTION close handler is explicitly defined in a MENU dialog, the handler code will be executed if the close action is fired.

If no explicit ON ACTION close action handler is defined, the code of the COMMAND KEY(INTERRUPT) or ON ACTION cancel will be executed, if defined.

If neither COMMAND KEY(INTERRUPT) nor ON ACTION cancel is defined:
  • If the MENU uses the default action views rendering, or with the attribute STYLE="dialog", nothing happens and the program stays in the MENU instruction.
  • If the MENU is defined with the attribute STYLE="popup", there is no X cross button to click. However, the Escape key, or a click outside the popup menu will terminate the MENU dialog.

The int_flag register is not touched by a MENU instruction.

The close action on mobile devices

When displaying on Android™ and iOS mobile device, the close action can be bound to the "Back button". For more details, see The Back button

Example

Implementing a close action handler, to open a confirmation dialog box, before leaving the dialog:

DIALOG ...
  INPUT BY NAME cust_rec.*
  END INPUT
  ...
  ON ACTION close
    IF msg_box_yn("Close this window?") == "y" THEN
      EXIT DIALOG
    END IF
  ...
END DIALOG