This class is used for idle events, which are generated when the system becomes idle. Note that, unless you do something specifically, the idle events are not sent if the system remains idle once it has become it, e.g. only a single idle event will be generated until something else resulting in more normal events happens and only then is the next idle event sent again. If you need to ensure a continuous stream of idle events, you can either use request_more method in your handler or call WakeUpIdle periodically (for example from timer event), but note that both of these approaches (and especially the first one) increase the system load and so should be avoided if possible.
By default, idle events are sent to all windows (and also App, as usual). If this is causing a significant overhead in your application, you can call IdleEvent#set_mode with the value IDLE_PROCESS_SPECIFIED, and set the WS_EX_PROCESS_IDLE extra window style for every window which should receive idle events.
To process an idle event, use this event handler macro to direct input to a member function that takes a IdleEvent argument.
| evt_idle() { | event | ... } | Process a EVT_IDLE event. |
Event handling overview, UpdateUIEvent, Window#on_internal_idle
Boolean can_send(Window window)Returns true if it is appropriate to send idle events to
this window.
This function looks at the mode used (see IdleEvent#set_mode),
and the WS_EX_PROCESS_IDLE style in window to determine whether idle events should be sent to
this window now. By default this will always return true because
the update mode is initially IDLE_PROCESS_ALL. You can change the mode
to only send idle events to windows with the WS_EX_PROCESS_IDLE extra window style set.
IdleMode get_mode()Static function returning a value specifying how Widgets will send idle events: to all windows, or only to those which specify that they will process the events.
See IdleEvent#set_mode.
request_more(Boolean needMore = true)Tells Widgets that more processing is required. This function can be called by an OnIdle handler for a window or window event handler to indicate that App::OnIdle should forward the OnIdle event once more to the application windows. If no window calls this function during OnIdle, then the application will remain in a passive event loop (not calling OnIdle) until a new event is posted to the application by the windowing system.
Boolean more_requested()Returns true if the OnIdle function processing this event requested more processing time.
set_mode(IdleMode mode)Static function for specifying how Widgets will send idle events: to all windows, or only to those which specify that they will process the events.
mode can be one of the following values. The default is IDLE_PROCESS_ALL.
enum IdleMode
{
// Send idle events to all windows
IDLE_PROCESS_ALL,
};// Send idle events to windows that have
// the WS_EX_PROCESS_IDLE flag specified
IDLE_PROCESS_SPECIFIED[This page automatically generated from the Textile source at Thu May 01 00:50:39 +0100 2008]