User interface programming / Dialog actions |
This topic describes the basics of action views, action events and action handlers.
In the user interface of the application, action views can produce action events, that will execute user code in the corresponding action handler defined in the current interactive instruction of the program.
Actions views are for example BUTTON form items.
Action handlers are ON ACTION or COMMAND dialog blocks that execute user code, in the current interactive dialog.
Action views are bound to action handlers by name.
If no action view is explicitly defined in the current form, the front end will create a "default action view" for the action. This is typically a button that appears in a specific area, located and decorated according to the front end platform standards.
Actions can be configured with action attributes. These can be defined explicitly at the action view level (button in form), as dialog-specific action configuration (ON ACTION name ATTRIBUTES(...)), or with action defaults.
Special actions are supported, such as the interrupt action to the user cancel a running application procedure.