Progress
AppBuilder
Developer’s Guide
Basic Pushbuttons
Pushbuttons came into existence along with the use of electricity in the 1800s. Simple switches, they are such a convenient user-interface device that they have now become nearly invisible because of how universally they are used.
In a GUI, a Pushbutton is equivalent in power and generality to a menu item. Indeed, you can construe a Pushbutton as being a self-contained, single-item menu. Since Pushbuttons are normally always visible, they offer more immediacy and convenience than menu items at the cost of taking up more space. Because they do take up more space, you will probably want to use them sparingly.
Because of how they are used in everyday life, Pushbuttons in a GUI are associated with invocations, actions, and major state changes, not with minor state changes such as setting a single value. Using them in a way that runs counter to this expectation can make your applications harder and less satisfying for people to use.
AppBuilder supplies a default, undefined Pushbutton object as well as a number of Pushbuttons preconfigured for common applications:
- View Page — Applies only to ADM paging (see the "Simple SmartContainers" section in Organizer Objects."). Causes objects associated with a certain page number to appear. You supply the number as an argument to the call in the trigger code. Already-visible objects assigned to other ADM pages do not disappear.
- OK, Cancel — Accepts/discards changes and closes the parent Dialog Box or Window.
- Done — Calls the application’s shutdown routine.
- Help — Calls the help system.
- First, Prev, Next, Last — Moves the current-record cursor to the record indicated by the button.
- Custom Size/Color — (Default) Creates a generic Pushbutton with no action defined on it. You must add the action code yourself in the CHOOSE trigger.
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