/*
* Copyright 2004, Joe English.
*
* Usage:
* TtkBlinkCursor(corePtr), usually called in a widget's Init hook,
* arranges to periodically toggle the corePtr->flags CURSOR_ON bit
* on and off (and schedule a redisplay) whenever the widget has focus.
*
* Note: Widgets may have additional logic to decide whether
* to display the cursor or not (e.g., readonly or disabled states);
* TtkBlinkCursor() does not account for this.
*
* TODO:
* Add script-level access to configure application-wide blink rate.
*/
#include <tk.h>
#include "ttkTheme.h"
#include "ttkWidget.h"
#define DEF_CURSOR_ON_TIME 600 /* milliseconds */
#define DEF_CURSOR_OFF_TIME 300 /* milliseconds */
/* Interp-specific data for tracking cursors:
*/
typedef struct
{
WidgetCore *owner; /* Widget that currently has cursor */
Tcl_TimerToken timer; /* Blink timer */
int onTime; /* #milliseconds to blink cursor on */
int offTime; /* #milliseconds to blink cursor off */
} CursorManager;
/* CursorManagerDeleteProc --
* InterpDeleteProc for cursor manager.
*/
static void CursorManagerDeleteProc(ClientData clientData, Tcl_Interp *interp)
{
CursorManager *cm = (CursorManager*)clientData;
if (cm->timer) {
Tcl_DeleteTimerHandler(cm->timer);
}
ckfree(clientData);
}
/* GetCursorManager --
* Look up and create if necessary the interp's cursor manager.
*/
static CursorManager *GetCursorManager(Tcl_Interp *interp)
{
static const char *cm_key = "ttk::CursorManager";
CursorManager *cm = Tcl_GetAssocData(interp, cm_key,0);
if (!cm) {
cm = ckalloc(sizeof(*cm));
cm->timer = 0;
cm->owner = 0;
cm->onTime = DEF_CURSOR_ON_TIME;
cm->offTime = DEF_CURSOR_OFF_TIME;
Tcl_SetAssocData(interp,cm_key,CursorManagerDeleteProc,(ClientData)cm);
}
return cm;
}
/* CursorBlinkProc --
* Timer handler to blink the insert cursor on and off.
*/
static void
CursorBlinkProc(ClientData clientData)
{
CursorManager *cm = (CursorManager*)clientData;
int blinkTime;
if (cm->owner->flags & CURSOR_ON) {
cm->owner->flags &= ~CURSOR_ON;
blinkTime = cm->offTime;
} else {
cm->owner->flags |= CURSOR_ON;
blinkTime = cm->onTime;
}
cm->timer = Tcl_CreateTimerHandler(blinkTime, CursorBlinkProc, clientData);
TtkRedisplayWidget(cm->owner);
}
/* LoseCursor --
* Turn cursor off, disable blink timer.
*/
static void LoseCursor(CursorManager *cm, WidgetCore *corePtr)
{
if (corePtr->flags & CURSOR_ON) {
corePtr->flags &= ~CURSOR_ON;
TtkRedisplayWidget(corePtr);
}
if (cm->owner == corePtr) {
cm->owner = NULL;
}
if (cm->timer) {
Tcl_DeleteTimerHandler(cm->timer);
cm->timer = 0;
}
}
/* ClaimCursor --
* Claim ownership of the insert cursor and blink on.
*/
static void ClaimCursor(CursorManager *cm, WidgetCore *corePtr)
{
if (cm->owner == corePtr)
return;
if (cm->owner)
LoseCursor(cm, cm->owner);
corePtr->flags |= CURSOR_ON;
TtkRedisplayWidget(corePtr);
cm->owner = corePtr;
cm->timer = Tcl_CreateTimerHandler(cm->onTime, CursorBlinkProc, cm);
}
/*
* CursorEventProc --
* Event handler for FocusIn and FocusOut events;
* claim/lose ownership of the insert cursor when the widget
* acquires/loses keyboard focus.
*/
#define CursorEventMask (FocusChangeMask|StructureNotifyMask)
#define RealFocusEvent(d) \
(d == NotifyInferior || d == NotifyAncestor || d == NotifyNonlinear)
static void
CursorEventProc(ClientData clientData, XEvent *eventPtr)
{
WidgetCore *corePtr = (WidgetCore *)clientData;
CursorManager *cm = GetCursorManager(corePtr->interp);
switch (eventPtr->type) {
case DestroyNotify:
if (cm->owner == corePtr)
LoseCursor(cm, corePtr);
Tk_DeleteEventHandler(
corePtr->tkwin, CursorEventMask, CursorEventProc, clientData);
break;
case FocusIn:
if (RealFocusEvent(eventPtr->xfocus.detail))
ClaimCursor(cm, corePtr);
break;
case FocusOut:
if (RealFocusEvent(eventPtr->xfocus.detail))
LoseCursor(cm, corePtr);
break;
}
}
/*
* TtkBlinkCursor (main routine) --
* Arrange to blink the cursor on and off whenever the
* widget has focus.
*/
void TtkBlinkCursor(WidgetCore *corePtr)
{
Tk_CreateEventHandler(
corePtr->tkwin, CursorEventMask, CursorEventProc, corePtr);
}
/*EOF*/
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