diff options
Diffstat (limited to 'macosx')
| -rw-r--r-- | macosx/tkMacOSXScrlbr.c | 59 |
1 files changed, 40 insertions, 19 deletions
diff --git a/macosx/tkMacOSXScrlbr.c b/macosx/tkMacOSXScrlbr.c index c6a8e29..0a5876d 100644 --- a/macosx/tkMacOSXScrlbr.c +++ b/macosx/tkMacOSXScrlbr.c @@ -11,7 +11,7 @@ * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tkMacOSXScrlbr.c,v 1.12 2005/05/15 21:09:34 wolfsuit Exp $ + * RCS: @(#) $Id: tkMacOSXScrlbr.c,v 1.13 2005/06/03 17:06:22 wolfsuit Exp $ */ #include "tkScrollbar.h" @@ -98,9 +98,11 @@ static ControlActionUPP scrollActionProc = NULL; /* Pointer to func. */ static ThumbActionUPP thumbActionProc = NULL; /* Pointer to func. */ static TkScrollbar *activeScrollPtr = NULL; /* Non-null when in thumb */ /* proc. */ -static Point activePoint; /* Used when - * activeScrollPtr is - * non-NULL */ +static Point mouseDownPoint; /* Used when activeScrollPtr is non-NULL */ + /* to store the coordinates where the */ + /* mouse was first pressed to begin */ + /* dragging the thumb, because */ + /* ThumbActionProc can't take any args. */ /* * Forward declarations for procedures defined later in this file: @@ -584,7 +586,7 @@ ThumbActionProc() register MacScrollbar *macScrollPtr = (MacScrollbar *) activeScrollPtr; Tcl_DString cmdString; int origValue; - double thumbWidth, newFirstFraction, trackBarSize; + double thumbWidth, oldFirstFraction, newFirstFraction, trackBarSize; char valueString[40]; Point currentPoint = { 0, 0 }; Rect trackRect; @@ -627,9 +629,16 @@ ThumbActionProc() /* * Track the mouse while the button is held down. If the mouse is moved, * we calculate the value that should be passed to the "command" part of - * the scrollbar. + * the scrollbar. Since the mouse may move a distance too small to + * cause a change to the first fraction, each calculation must be done + * versus what the first fraction was when the mouse button was + * initially pressed. Otherwise, moving the mouse too slowly will + * cause the calculated fraction delta to be zero and the scrollbar + * won't respond. */ + oldFirstFraction = scrollPtr->firstFraction; + do { err = TrackMouseLocationWithOptions(NULL, kTrackMouseLocationOptionDontConsumeMouseUp, @@ -641,18 +650,25 @@ ThumbActionProc() if ((err == noErr) && ((trackingResult == kMouseTrackingMouseDragged) || (trackingResult == kMouseTrackingMouseMoved))) { - /* - * Calculate where the scrollbar should move to, and reset the - * activePoint to where we are now. - */ - newFirstFraction = scrollPtr->firstFraction; + + /* + * Calculate where the scrollbar should move to, based on + * where the mouse button was pressed and where the scrollbar + * initially was at that time. Note that PtInRect() will + * return false if currentPoint or trackRect are not in + * is not in current graphics port, which may happen if any + * of the waiting idle events change the port (e.g. with + * SetPort()) but fail to restore it before returning and the + * scrollbar will lock in place. + */ + newFirstFraction = oldFirstFraction; if (PtInRect(currentPoint, &trackRect)) { double pixDiff; double fracDelta; if (scrollPtr->vertical == true) { - pixDiff = (double)(currentPoint.v - activePoint.v); + pixDiff = (double)(currentPoint.v - mouseDownPoint.v); } else { - pixDiff = (double)(currentPoint.h - activePoint.h); + pixDiff = (double)(currentPoint.h - mouseDownPoint.h); } fracDelta = pixDiff/(trackBarSize); newFirstFraction += fracDelta; @@ -663,8 +679,13 @@ ThumbActionProc() } } - activePoint = currentPoint; - + /* + * Move the scrollbar thumb to the new first fraction given + * its position when initially pressed and how far the mouse + * has moved. Process waiting idle tasks afterward to allow + * for the display to update. + */ + sprintf(valueString, "%g", newFirstFraction); Tcl_DStringSetLength(&cmdString, 0); Tcl_DStringAppend(&cmdString, scrollPtr->command, @@ -674,9 +695,9 @@ ThumbActionProc() interp = scrollPtr->interp; Tcl_Preserve((ClientData) interp); Tcl_GlobalEval(interp, cmdString.string); - Tcl_Release ((ClientData) interp); + Tcl_Release((ClientData) interp); - TclServiceIdle(); + TclServiceIdle(); } } while ((err == noErr) && trackingResult != kMouseTrackingMouseReleased); @@ -799,8 +820,8 @@ ScrollbarBindProc( * so the callback may have access to it. */ activeScrollPtr = scrollPtr; - activePoint.h = where.h; - activePoint.v = where.v; + mouseDownPoint.h = where.h; + mouseDownPoint.v = where.v; part = TrackControl(macScrollPtr->sbHandle, where, (ControlActionUPP) thumbActionProc); activeScrollPtr = NULL; |