Ev_Captureevents - Texas Instruments TI-89 Developer's Manual

Appendix A: System Routines — Operating System

EV_captureEvents

Declaration: EV_entryPoint EV_captureEvents (EV_entryPoint callback )
Category(ies): Operating System
Description: Redirects all events to callback . Use this routine to capture events if you
are creating your own dialog or menu managers.
Save the returned value and use it to restore event processing when you
are finished capturing events.
Inputs: callback — The address of a routine which accepts one parameter, an
Outputs: Returns pointer to previously captured event handler.
Assumptions: None
Side Effects: None
Availability: All versions of the TI-89 / TI-92 Plus.
TI-89 / TI-92 Plus
Differences: None
See Also: Not applicable.
Example: MyDialog opens a window and captures events. All subsequent events are
sent to myEventHandler. Routine myEventHandler calls cancel when it is
finished handling events. Routine cancel closes the dialog window and
restores normal event dispatching.
WINDOW myWindow;
EV_eventPoint oldEventHandler;
EV_FLAGS oldPaintState;
void MyDialog(void)
/* Initialize my display */
{
static const WIN_RECT r = {
(W_MAX_X - WINDOW_WIDTH*LF_WIDTH(' '))/2,
WINDOW_TOP,
(W_MAX_X + WINDOW_WIDTH*LF_WIDTH(' '))/2 + 1,
WINDOW_TOP+W_TITLE_Y+WINDOW_HEIGHT*LF_HEIGHT + 1
};
oldPaintState = EV_suspendPainting();
TI-89 / TI-92 Plus Developer Guide
event pointer.
(continued)
Not for Distribution
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Beta Version January 26, 2001