Added tracking areas to Area on Mac OS X so mouse move events can work; they work now.

area_darwin.go

@@ -12,6 +12,7 @@ import (
 //// #include <HIToolbox/Events.h>
 // #include "objc_darwin.h"
 // extern BOOL areaView_isFlipped_acceptsFirstResponder(id, SEL);
+// extern void areaView_updateTrackingAreas(id, SEL);
 // extern void areaView_mouseMoved_mouseDragged(id, SEL, id);
 // extern void areaView_mouseDown(id, SEL, id);
 // extern void areaView_mouseUp(id, SEL, id);
@@ -36,6 +37,8 @@ var goAreaSels = []selector{
 		"ensuring that an Area's coordinate system has (0,0) at the top-left corner"},
 	selector{"acceptsFirstResponder", uintptr(C.areaView_isFlipped_acceptsFirstResponder), sel_bool,
 		"registering that Areas are to receive events"},
+	selector{"updateTrackingAreas", uintptr(C.areaView_updateTrackingAreas), sel_void,
+		"updating tracking areas for handling mouse movements in Area"},
 	selector{"mouseMoved:", uintptr(C.areaView_mouseMoved_mouseDragged), sel_void_id,
 		"handling mouse movements in Area"},
 	selector{"mouseDown:", uintptr(C.areaView_mouseDown), sel_void_id,
@@ -78,6 +81,7 @@ func makeArea(parentWindow C.id, alternate bool, s *sysData) C.id {
 	area := C.objc_msgSend_noargs(_goArea, _alloc)
 	area = initWithDummyFrame(area)
 	// TODO others?
+	retrack(area, s)
 	area = newScrollView(area)
 	addControl(parentWindow, area)
 	return area
@@ -117,6 +121,24 @@ func areaView_isFlipped_acceptsFirstResponder(self C.id, sel C.SEL) C.BOOL {
 	return C.BOOL(C.YES)
 }
 
+var (
+	_addTrackingArea = sel_getUid("addTrackingArea:")
+	_removeTrackingArea = sel_getUid("removeTrackingArea:")
+)
+
+func retrack(area C.id, s *sysData) {
+	s.trackingArea = C.makeTrackingArea(area)
+	C.objc_msgSend_id(area, _addTrackingArea, s.trackingArea)
+}
+
+//export areaView_updateTrackingAreas
+func areaView_updateTrackingAreas(self C.id, sel C.SEL) {
+	s := getSysData(self)
+	C.objc_msgSend_id(self, _removeTrackingArea, s.trackingArea)
+	C.objc_msgSend_noargs(s.trackingArea, _release)
+	retrack(self, s)
+}
+
 var (
 	_NSEvent = objc_getClass("NSEvent")
 
@@ -175,6 +197,7 @@ func areaMouseEvent(self C.id, e C.id, click bool, up bool) {
 		which = 0			// reset for Held processing below
 	}
 	// pressedMouseButtons is a class method; calling objc_msgSend() directly with e as an argument on these will panic (in real Objective-C the compiler can detect [e pressedMouseButtons])
+	// the docs do say don't use this for tracking since it returns the state now, and mouse move events work by tracking, but as far as I can tell dragging the mouse over the inactive window does n ot generate an event on Mac OS X, so :/ (TODO see what happens when the program is the current one; in my own separate tests no harm was done so eh; also no need for this if tracking doesn't touch dragging)
 	held := C.objc_msgSend_uintret_noargs(_NSEvent, _pressedMouseButtons)
 	if which != 1 && (held & 1) != 0 {		// button 1
 		me.Held = append(me.Held, 1)
@@ -200,8 +223,8 @@ func areaMouseEvent(self C.id, e C.id, click bool, up bool) {
 
 //export areaView_mouseMoved_mouseDragged
 func areaView_mouseMoved_mouseDragged(self C.id, sel C.SEL, e C.id) {
+	// for moving, this is handled by the tracking rect stuff above
 	// for dragging, if multiple buttons are held, only one of their xxxMouseDragged: messages will be sent, so this is OK to do
-	// TODO implement tracking for dragging
 	areaMouseEvent(self, e, false, false)
 }
 

bleh_darwin.m

@@ -21,6 +21,7 @@ though this is not always the case.
 #include <AppKit/NSBitmapImageRep.h>
 #include <AppKit/NSCell.h>
 #include <AppKit/NSApplication.h>
+#include <AppKit/NSTrackingArea.h>
 
 /* used by listbox_darwin.go; requires NSString */
 id *_NSObservedObjectKey = (id *) (&NSObservedObjectKey);
@@ -43,6 +44,9 @@ static id c_NSFont;
 static SEL s_setFont;				/* objc_setFont() */
 static SEL s_systemFontOfSize;
 static SEL s_systemFontSizeForControlSize;
+static id c_NSTrackingArea;
+static SEL s_bounds;
+static SEL s_initTrackingArea;
 
 void initBleh()
 {
@@ -60,6 +64,9 @@ void initBleh()
 	s_setFont = sel_getUid("setFont:");
 	s_systemFontOfSize = sel_getUid("systemFontOfSize:");
 	s_systemFontSizeForControlSize = sel_getUid("systemFontSizeForControlSize:");
+	c_NSTrackingArea = objc_getClass("NSTrackingArea");
+	s_bounds = sel_getUid("bounds");
+	s_initTrackingArea = sel_getUid("initWithRect:options:owner:userInfo:");
 }
 
 /*
@@ -350,3 +357,25 @@ static NSApplicationTerminateReply __appDelegate_applicationShouldTerminate(id s
 void *_appDelegate_applicationShouldTerminate = (void *) __appDelegate_applicationShouldTerminate;
 
 char *encodedTerminateReply = @encode(NSApplicationTerminateReply);
+
+/*
+tracking areas; also here for convenience only
+*/
+
+/* IDK if this is needed; just to be safe */
+static id (*objc_msgSend_initTrackingArea)(id, SEL, NSRect, NSTrackingAreaOptions, id, id) =
+	(id (*)(id, SEL, NSRect, NSTrackingAreaOptions, id, id)) objc_msgSend;
+
+id makeTrackingArea(id area)
+{
+	id trackingArea;
+
+	trackingArea = objc_msgSend(c_NSTrackingArea, s_alloc);
+	trackingArea = (*objc_msgSend_initTrackingArea)(trackingArea, s_initTrackingArea,
+		(*objc_msgSend_stret_rect)(area, s_bounds),			/* initWithRect: */
+		/* this bit mask (except for NSTrackingInVisibleRect, which was added later) comes from https://github.com/andlabs/misctestprogs/blob/master/cocoaviewmousetest.m (and I wrote this bit mask on 25 april 2014) and yes I know it includes enter/exit even though we don't watch those events; it probably won't really matter anyway but if it does I can change it easily */
+		(NSTrackingAreaOptions) (NSTrackingMouseEnteredAndExited | NSTrackingMouseMoved | NSTrackingActiveAlways | NSTrackingEnabledDuringMouseDrag | NSTrackingInVisibleRect),			/* options: */
+		area,											/* owner: */
+		nil);											/* userData: */
+	return trackingArea;
+}

objc_darwin.go

@@ -98,6 +98,7 @@ const (
 	sel_bool
 	sel_void_rect
 	sel_terminatereply_id
+	sel_void
 	nitypes
 )
 
@@ -107,6 +108,7 @@ var itypes = [nitypes][]C.char{
 	sel_bool:				[]C.char{'c', '@', ':', 0},
 	sel_void_rect:			nil,			// see init() below
 	sel_terminatereply_id:	nil,
+	sel_void:				[]C.char{'v', '@', ':', 0},
 }
 
 func init() {

objc_darwin.h

@@ -112,8 +112,10 @@ extern void initBleh();
 extern id makeDummyEvent();
 
 /* for area_darwin.go */
+/* TODO apparently ISO C forbids casting a function pointer to a non-function pointer; this will need to change???? */
 extern void *_areaView_drawRect;
 extern void drawImage(void *, int64_t, int64_t, int64_t, int64_t, int64_t);
+extern id makeTrackingArea(id);
 extern struct xpoint getTranslatedEventPoint(id, id);
 
 /* for objc_darwin.go */

sysdata_darwin.go

@@ -50,7 +50,6 @@ var (
 	_initWithContentRect = sel_getUid("initWithContentRect:styleMask:backing:defer:")
 	_initWithFrame = sel_getUid("initWithFrame:")
 	_setDelegate = sel_getUid("setDelegate:")
-	_setAcceptsMouseMovedEvents = sel_getUid("setAcceptsMouseMovedEvents:")
 	_makeKeyAndOrderFront = sel_getUid("makeKeyAndOrderFront:")
 	_orderOut = sel_getUid("orderOut:")
 	_setHidden = sel_getUid("setHidden:")
@@ -147,8 +146,7 @@ var classTypes = [nctypes]*classData{
 				C.uintptr_t(_NSBackingStoreBuffered),
 				C.BOOL(C.YES))			// defer creation of device until we show the window
 			C.objc_msgSend_id(win, _setDelegate, appDelegate)
-			// this is needed for Areas in the window to receive mouse move events
+			// we do not need setAcceptsMouseMovedEvents: here since we are using a tracking rect in Areas for that
-//			C.objc_msgSend_bool(win, _setAcceptsMouseMovedEvents, C.BOOL(C.YES))
 			return win
 		},
 		show:		func(what C.id) {