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 RequestMore method in your handler or call wxWakeUpIdle 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 wxApp, as usual). If this is causing a significant overhead in your application, you can call wxIdleEvent::SetMode with the value wxIDLE_PROCESS_SPECIFIED, and set the wxWS_EX_PROCESS_IDLE extra window style for every window which should receive idle events.
Derived from
Include files
<wx/event.h>
Event table macros
To process an idle event, use this event handler macro to direct input to a member function that takes a wxIdleEvent argument.
| EVT_IDLE(func) | Process a wxEVT_IDLE event. |
Event handling overview, wxUpdateUIEvent, wxWindow::OnInternalIdle
Members
wxIdleEvent::wxIdleEvent
wxIdleEvent::CanSend
wxIdleEvent::GetMode
wxIdleEvent::RequestMore
wxIdleEvent::MoreRequested
wxIdleEvent::SetMode
wxIdleEvent()
Constructor.
static bool CanSend(wxWindow* window)
Returns true if it is appropriate to send idle events to this window.
This function looks at the mode used (see wxIdleEvent::SetMode), and the wxWS_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 wxIDLE_PROCESS_ALL. You can change the mode to only send idle events to windows with the wxWS_EX_PROCESS_IDLE extra window style set.
See also
static wxIdleMode GetMode()
Static function returning a value specifying how wxWidgets will send idle events: to all windows, or only to those which specify that they will process the events.
See wxIdleEvent::SetMode.
void RequestMore(bool needMore = true)
Tells wxWidgets that more processing is required. This function can be called by an OnIdle handler for a window or window event handler to indicate that wxApp::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.
See also
bool MoreRequested() const
Returns true if the OnIdle function processing this event requested more processing time.
See also
static void SetMode(wxIdleMode mode)
Static function for specifying how wxWidgets 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 wxIDLE_PROCESS_ALL.
enum wxIdleMode
{
// Send idle events to all windows
wxIDLE_PROCESS_ALL,
// Send idle events to windows that have
// the wxWS_EX_PROCESS_IDLE flag specified
wxIDLE_PROCESS_SPECIFIED
};