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New eventb based Drag interface for wxDataViewCtrl
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fb896a32 1/////////////////////////////////////////////////////////////////////////////
8898456d 2// Name: src/cocoa/app.mm
fb896a32
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3// Purpose: wxApp
4// Author: David Elliott
5// Modified by:
6// Created: 2002/11/27
d89d4059 7// RCS-ID: $Id$
fb896a32 8// Copyright: (c) David Elliott
047c1182 9// Software 2000 Ltd.
bb27b372 10// Licence: wxWidgets licence
fb896a32
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11/////////////////////////////////////////////////////////////////////////////
12
fb896a32 13#include "wx/wxprec.h"
8898456d 14
da80ae71
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15#include "wx/app.h"
16
fb896a32 17#ifndef WX_PRECOMP
fb896a32
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18 #include "wx/intl.h"
19 #include "wx/log.h"
02761f6c 20 #include "wx/module.h"
fb896a32
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21#endif
22
047c1182 23#include "wx/cocoa/ObjcRef.h"
493902ac 24#include "wx/cocoa/autorelease.h"
af367f46 25#include "wx/cocoa/mbarman.h"
bb27b372 26#include "wx/cocoa/NSApplication.h"
fb45bb1f 27
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28#include "wx/cocoa/dc.h"
29
fb896a32
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30#import <AppKit/NSApplication.h>
31#import <Foundation/NSRunLoop.h>
14fc7eb4 32#import <Foundation/NSThread.h>
aaa5ab05 33#import <AppKit/NSEvent.h>
eb537cfb 34#import <Foundation/NSString.h>
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35#import <Foundation/NSNotification.h>
36#import <AppKit/NSCell.h>
fb896a32 37
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38bool wxApp::sm_isEmbedded = false; // Normally we're not a plugin
39
047c1182 40// wxNSApplicationObserver singleton.
a24aa427 41static wxObjcAutoRefFromAlloc<wxNSApplicationObserver*> sg_cocoaAppObserver = [[WX_GET_OBJC_CLASS(wxNSApplicationObserver) alloc] init];
047c1182 42
ba808e24
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43// ========================================================================
44// wxNSApplicationDelegate
45// ========================================================================
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46@implementation wxNSApplicationDelegate : NSObject
47
2990ec97 48// NOTE: Terminate means that the event loop does NOT return and thus
bb27b372 49// cleanup code doesn't properly execute. Furthermore, wxWidgets has its
2990ec97 50// own exit on frame delete mechanism.
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51- (BOOL)applicationShouldTerminateAfterLastWindowClosed:(NSApplication *)theApplication
52{
2990ec97 53 return NO;
fb896a32
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54}
55
047c1182 56@end // implementation wxNSApplicationDelegate : NSObject
a24aa427 57WX_IMPLEMENT_GET_OBJC_CLASS(wxNSApplicationDelegate,NSObject)
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58
59// ========================================================================
60// wxNSApplicationObserver
61// ========================================================================
62@implementation wxNSApplicationObserver : NSObject
63
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64- (void)applicationWillBecomeActive:(NSNotification *)notification
65{
66 wxTheApp->CocoaDelegate_applicationWillBecomeActive();
67}
68
69- (void)applicationDidBecomeActive:(NSNotification *)notification
70{
71 wxTheApp->CocoaDelegate_applicationDidBecomeActive();
72}
73
74- (void)applicationWillResignActive:(NSNotification *)notification
75{
76 wxTheApp->CocoaDelegate_applicationWillResignActive();
77}
78
79- (void)applicationDidResignActive:(NSNotification *)notification
80{
81 wxTheApp->CocoaDelegate_applicationDidResignActive();
82}
83
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84- (void)applicationWillUpdate:(NSNotification *)notification;
85{
86 wxTheApp->CocoaDelegate_applicationWillUpdate();
87}
88
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89- (void)controlTintChanged:(NSNotification *)notification
90{
422d306c 91 wxLogDebug(wxT("TODO: send EVT_SYS_COLOUR_CHANGED as appropriate"));
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92}
93
047c1182 94@end // implementation wxNSApplicationObserver : NSObject
a24aa427 95WX_IMPLEMENT_GET_OBJC_CLASS(wxNSApplicationObserver,NSObject)
e2478fde 96
70fb935a
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97// ========================================================================
98// wxApp
99// ========================================================================
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100
101// ----------------------------------------------------------------------------
102// wxApp Static member initialization
103// ----------------------------------------------------------------------------
fb896a32 104IMPLEMENT_DYNAMIC_CLASS(wxApp, wxEvtHandler)
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105
106// ----------------------------------------------------------------------------
05e2b077 107// wxApp initialization/cleanup
fb896a32 108// ----------------------------------------------------------------------------
05e2b077 109bool wxApp::Initialize(int& argc, wxChar **argv)
fb896a32 110{
47f1ad6a 111 wxAutoNSAutoreleasePool pool;
14fc7eb4 112 m_cocoaMainThread = [NSThread currentThread];
05e2b077
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113 // Mac OS X passes a process serial number command line argument when
114 // the application is launched from the Finder. This argument must be
115 // removed from the command line arguments before being handled by the
116 // application (otherwise applications would need to handle it)
117 if ( argc > 1 )
118 {
119 static const wxChar *ARG_PSN = _T("-psn_");
b0c0a393 120 if ( wxStrncmp(argv[1], ARG_PSN, wxStrlen(ARG_PSN)) == 0 )
05e2b077
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121 {
122 // remove this argument
33f39af3 123 --argc;
b0c0a393 124 memmove(argv + 1, argv + 2, argc * sizeof(wxChar *));
05e2b077
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125 }
126 }
127
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128 /*
129 Cocoa supports -Key value options which set the user defaults key "Key"
130 to the value "value" Some of them are very handy for debugging like
131 -NSShowAllViews YES. Cocoa picks these up from the real argv so
132 our removal of them from the wx copy of it does not affect Cocoa's
133 ability to see them.
134
135 We basically just assume that any "-NS" option and its following
136 argument needs to be removed from argv. We hope that user code does
137 not expect to see -NS options and indeed it's probably a safe bet
138 since most user code accepting options is probably using the
139 double-dash GNU-style syntax.
140 */
141 for(int i=1; i < argc; ++i)
142 {
143 static const wxChar *ARG_NS = wxT("-NS");
144 static const int ARG_NS_LEN = wxStrlen(ARG_NS);
145 if( wxStrncmp(argv[i], ARG_NS, ARG_NS_LEN) == 0 )
146 {
147 // Only eat this option if it has an argument
148 if( (i + 1) < argc )
149 {
150 argc -= 2;
151 memmove(argv + i, argv + i + 2, argc * sizeof(wxChar*));
152 // drop back one position so the next run through the loop
153 // reprocesses the argument at our current index.
154 --i;
155 }
156 }
157 }
158
94826170 159 return wxAppBase::Initialize(argc, argv);
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160}
161
94826170 162void wxApp::CleanUp()
fb896a32 163{
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164 wxAutoNSAutoreleasePool pool;
165
938156b2 166 wxCocoaDCImpl::CocoaShutdownTextSystem();
af367f46 167 wxMenuBarManager::DestroyInstance();
94826170 168
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169 [[NSNotificationCenter defaultCenter] removeObserver:sg_cocoaAppObserver];
170 if(!sm_isEmbedded)
171 {
172 [m_cocoaApp setDelegate:nil];
173 [m_cocoaAppDelegate release];
174 m_cocoaAppDelegate = NULL;
175 }
0187ddb4 176
94826170 177 wxAppBase::CleanUp();
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178}
179
180// ----------------------------------------------------------------------------
181// wxApp creation
182// ----------------------------------------------------------------------------
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183wxApp::wxApp()
184{
185 m_topWindow = NULL;
fb896a32 186
b93d8cc4 187#ifdef __WXDEBUG__
8898456d 188 m_isInAssert = false;
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189#endif // __WXDEBUG__
190
fb896a32 191 argc = 0;
b95d7ac9 192#if !wxUSE_UNICODE
fb896a32 193 argv = NULL;
b95d7ac9 194#endif
fb896a32 195 m_cocoaApp = NULL;
0187ddb4 196 m_cocoaAppDelegate = NULL;
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197}
198
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199void wxApp::CocoaDelegate_applicationWillBecomeActive()
200{
201}
202
203void wxApp::CocoaDelegate_applicationDidBecomeActive()
204{
205}
206
207void wxApp::CocoaDelegate_applicationWillResignActive()
208{
39050120 209 wxTopLevelWindowCocoa::DeactivatePendingWindow();
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210}
211
212void wxApp::CocoaDelegate_applicationDidResignActive()
213{
214}
215
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216bool wxApp::OnInitGui()
217{
47f1ad6a 218 wxAutoNSAutoreleasePool pool;
fb896a32 219 if(!wxAppBase::OnInitGui())
8898456d 220 return false;
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221
222 // Create the app using the sharedApplication method
223 m_cocoaApp = [NSApplication sharedApplication];
047c1182 224
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225 if(!sm_isEmbedded)
226 {
227 // Enable response to application delegate messages
a24aa427 228 m_cocoaAppDelegate = [[WX_GET_OBJC_CLASS(wxNSApplicationDelegate) alloc] init];
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229 [m_cocoaApp setDelegate:m_cocoaAppDelegate];
230 }
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231
232 // Enable response to "delegate" messages on the notification observer
233 [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
234 selector:@selector(applicationWillBecomeActive:)
235 name:NSApplicationWillBecomeActiveNotification object:nil];
236
237 [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
238 selector:@selector(applicationDidBecomeActive:)
239 name:NSApplicationDidBecomeActiveNotification object:nil];
240
241 [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
242 selector:@selector(applicationWillResignActive:)
243 name:NSApplicationWillResignActiveNotification object:nil];
244
245 [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
246 selector:@selector(applicationDidResignActive:)
247 name:NSApplicationDidResignActiveNotification object:nil];
248
249 [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
250 selector:@selector(applicationWillUpdate:)
251 name:NSApplicationWillUpdateNotification object:nil];
252
253 // Enable response to system notifications
254 [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
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255 selector:@selector(controlTintChanged:)
256 name:NSControlTintDidChangeNotification object:nil];
af367f46 257
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258 if(!sm_isEmbedded)
259 wxMenuBarManager::CreateInstance();
af367f46 260
938156b2 261 wxCocoaDCImpl::CocoaInitializeTextSystem();
8898456d 262 return true;
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263}
264
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265wxApp::~wxApp()
266{
267 if(m_cfRunLoopIdleObserver != NULL)
268 {
269 // Invalidate the observer which also removes it from the run loop.
270 CFRunLoopObserverInvalidate(m_cfRunLoopIdleObserver);
271 // Release the ref as we don't need it anymore.
272 m_cfRunLoopIdleObserver.reset();
273 }
274}
275
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276bool wxApp::CallOnInit()
277{
bd3e8827 278// wxAutoNSAutoreleasePool pool;
47f1ad6a
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279 return OnInit();
280}
281
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282bool wxApp::OnInit()
283{
284 if(!wxAppBase::OnInit())
8898456d 285 return false;
fb896a32 286
8898456d 287 return true;
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288}
289
70fb935a
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290void wxApp::Exit()
291{
292 wxApp::CleanUp();
293
294 wxAppConsole::Exit();
295}
296
fb896a32 297// Yield to other processes
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298bool wxApp::Yield(bool onlyIfNeeded)
299{
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300#if wxUSE_LOG
301 // disable log flushing from here because a call to wxYield() shouldn't
302 // normally result in message boxes popping up &c
303 wxLog::Suspend();
304#endif // wxUSE_LOG
305
d181e877 306 if (m_isInsideYield)
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307 {
308 if ( !onlyIfNeeded )
309 {
310 wxFAIL_MSG( wxT("wxYield called recursively" ) );
311 }
312
313 return false;
314 }
315
d181e877 316 m_isInsideYield = true;
fb896a32 317
aaa5ab05 318 // Run the event loop until it is out of events
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319 while(1)
320 {
321 wxAutoNSAutoreleasePool pool;
30cfcda5
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322 /* NOTE: It may be better to use something like
323 NSEventTrackingRunLoopMode since we don't necessarily want all
324 timers/sources/observers to run, only those which would
325 run while tracking events. However, it should be noted that
326 NSEventTrackingRunLoopMode is in the common set of modes
327 so it may not effectively make much of a difference.
328 */
bb27b372 329 NSEvent *event = [GetNSApplication()
aaa5ab05 330 nextEventMatchingMask:NSAnyEventMask
422d306c 331 untilDate:[NSDate distantPast]
aaa5ab05 332 inMode:NSDefaultRunLoopMode
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333 dequeue: YES];
334 if(!event)
335 break;
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336 [GetNSApplication() sendEvent: event];
337 }
fb896a32 338
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339 /*
340 Because we just told NSApplication to avoid blocking it will in turn
341 run the CFRunLoop with a timeout of 0 seconds. In that case, our
342 run loop observer on kCFRunLoopBeforeWaiting never fires because
343 no waiting occurs. Therefore, no idle events are sent.
344
345 Believe it or not, this is actually desirable because we do not want
346 to process idle from here. However, we do want to process pending
347 events because some user code expects to do work in a thread while
348 the main thread waits and then notify the main thread by posting
349 an event.
350 */
351 ProcessPendingEvents();
352
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353#if wxUSE_LOG
354 // let the logs be flashed again
355 wxLog::Resume();
356#endif // wxUSE_LOG
357
d181e877 358 m_isInsideYield = false;
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359
360 return true;
361}
362
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363void wxApp::WakeUpIdle()
364{
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365 /* When called from the main thread the NSAutoreleasePool managed by
366 the [NSApplication run] method would ordinarily be in place and so
367 one would think a pool here would be unnecessary.
368
369 However, when called from a different thread there is usually no
370 NSAutoreleasePool in place because wxThread has no knowledge of
371 wxCocoa. The pool here is generally only ever going to contain
372 the NSEvent we create with the factory method. As soon as we add
373 it to the main event queue with postEvent:atStart: it is retained
374 and so safe for our pool to release.
375 */
376 wxAutoNSAutoreleasePool pool;
377 /* NOTE: This is a little heavy handed. What this does is cause an
378 AppKit NSEvent to be added to NSApplication's queue (which is always
379 on the main thread). This will cause the main thread runloop to
380 exit which returns control to nextEventMatchingMask which returns
381 the event which is then sent with sendEvent: and essentially dropped
382 since it's not for a window (windowNumber 0) and NSApplication
383 certainly doesn't understand it.
384
385 With the exception of wxEventLoop::Exit which uses us to cause the
386 runloop to exit and return to the NSApplication event loop, most
387 callers only need wx idle to happen, or more specifically only really
388 need to ensure that ProcessPendingEvents is called which is currently
389 done without exiting the runloop.
390
391 Be careful if you decide to change the implementation of this method
392 as wxEventLoop::Exit depends on the current behavior.
393 */
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394 [m_cocoaApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
395 location:NSZeroPoint modifierFlags:NSAnyEventMask
396 timestamp:0 windowNumber:0 context:nil
397 subtype:0 data1:0 data2:0] atStart:NO];
398}
399
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400extern "C" static void ObserveMainRunLoopBeforeWaiting(CFRunLoopObserverRef observer, CFRunLoopActivity activity, void *info);
401extern "C" static void ObserveMainRunLoopBeforeWaiting(CFRunLoopObserverRef observer, CFRunLoopActivity activity, void *info)
402{
403 static_cast<wxApp*>(info)->CF_ObserveMainRunLoopBeforeWaiting(observer, activity);
404}
405
406#if 0
407static int sg_cApplicationWillUpdate = 0;
408#endif
409
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410/*!
411 Invoked from the applicationWillUpdate notification observer. See the
412 NSApplication documentation for the official statement on when this
413 will be called. Since it can be hard to understand for a Cocoa newbie
414 I'll try to explain it here as it relates to wxCocoa.
415
416 Basically, we get called from within nextEventMatchingMask if and only
417 if any user code told the application to send the update notification
418 (sort of like a request for idle events). However, unlike wx idle events,
419 this notification is sent quite often, nearly every time through the loop
420 because nearly every control tells the application to send it.
421
422 Because wx idle events are only supposed to be sent when the event loop
423 is about to block we instead schedule a function to be called just
424 before the run loop waits and send the idle events from there.
425
426 It also has the desirable effect of only sending the wx idle events when
427 the event loop is actualy going to block. If the event loop is being
428 pumped manualy (e.g. like a PeekMessage) then the kCFRunLoopBeforeWaiting
429 observer never fires. Our Yield() method depends on this because sending
430 idle events from within Yield would be bad.
431
432 Normally you might think that we could just set the observer up once and
433 leave it attached. However, this is problematic because our run loop
434 observer calls user code (the idle handlers) which can actually display
435 modal dialogs. Displaying a modal dialog causes reentry of the event
436 loop, usually in a different run loop mode than the main loop (e.g. in
437 modal-dialog mode instead of default mode). Because we only register the
438 observer with the run loop mode at the time of this call, it won't be
439 called from a modal loop.
440
441 We want it to be called and thus we need a new observer.
442 */
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443void wxApp::CocoaDelegate_applicationWillUpdate()
444{
445 wxLogTrace(wxTRACE_COCOA,wxT("applicationWillUpdate"));
446
447// CFRunLoopRef cfRunLoop = [[NSRunLoop currentRunLoop] getCFRunLoop];
448 CFRunLoopRef cfRunLoop = CFRunLoopGetCurrent();
449 wxCFRef<CFStringRef> cfRunLoopMode(CFRunLoopCopyCurrentMode(cfRunLoop));
450
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451 /* If we have an observer and that observer is for the wrong run loop
452 mode then invalidate it and release it.
453 */
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454 if(m_cfRunLoopIdleObserver != NULL && m_cfObservedRunLoopMode != cfRunLoopMode)
455 {
456 CFRunLoopObserverInvalidate(m_cfRunLoopIdleObserver);
457 m_cfRunLoopIdleObserver.reset();
458 }
459#if 0
460 ++sg_cApplicationWillUpdate;
461#endif
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462 /* This will be true either on the first call or when the above code has
463 invalidated and released the exisiting observer.
464 */
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465 if(m_cfRunLoopIdleObserver == NULL)
466 {
467 // Enable idle event handling
468 CFRunLoopObserverContext observerContext =
469 { 0
470 , this
471 , NULL
472 , NULL
473 , NULL
474 };
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475 /* NOTE: I can't recall why we don't just let the observer repeat
476 instead of invalidating itself each time it fires thus requiring
477 it to be recreated for each shot but there was if I remember
478 some good (but very obscure) reason for it.
479
480 On the other hand, I could be wrong so don't take that as gospel.
481 */
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482 m_cfRunLoopIdleObserver.reset(CFRunLoopObserverCreate(kCFAllocatorDefault, kCFRunLoopBeforeWaiting, /*repeats*/FALSE, /*priority*/0, ObserveMainRunLoopBeforeWaiting, &observerContext));
483 m_cfObservedRunLoopMode = cfRunLoopMode;
484 CFRunLoopAddObserver(cfRunLoop, m_cfRunLoopIdleObserver, m_cfObservedRunLoopMode);
485 }
486}
487
488static inline bool FakeNeedMoreIdle()
489{
490#if 0
491// Return true on every 10th call.
492 static int idleCount = 0;
493 return ++idleCount % 10;
494#else
495 return false;
496#endif
497}
498
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499/*!
500 Called by CFRunLoop just before waiting. This is the appropriate time to
501 send idle events. Unlike other ports, we don't peek the queue for events
502 and stop idling if there is one. Instead, if the user requests more idle
503 events we tell Cocoa to send us an applicationWillUpdate notification
504 which will cause our observer of that notification to tell CFRunLoop to
505 call us before waiting which will cause us to be fired again but only
506 after exhausting the event queue.
507
508 The reason we do it this way is that peeking for an event causes CFRunLoop
509 to reenter and fire off its timers, observers, and sources which we're
510 better off avoiding. Doing it this way, we basically let CFRunLoop do the
511 work of peeking for the next event which is much nicer.
512 */
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513void wxApp::CF_ObserveMainRunLoopBeforeWaiting(CFRunLoopObserverRef observer, int activity)
514{
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515 // Ensure that CocoaDelegate_applicationWillUpdate will recreate us.
516 // We've already been invalidated by CFRunLoop because we are one-shot.
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517 m_cfRunLoopIdleObserver.reset();
518#if 0
519 wxLogTrace(wxTRACE_COCOA,wxT("Idle BEGIN (%d)"), sg_cApplicationWillUpdate);
520 sg_cApplicationWillUpdate = 0;
521#else
522 wxLogTrace(wxTRACE_COCOA,wxT("Idle BEGIN"));
523#endif
524 if( ProcessIdle() || FakeNeedMoreIdle() )
525 {
526 wxLogTrace(wxTRACE_COCOA, wxT("Idle REQUEST MORE"));
527 [NSApp setWindowsNeedUpdate:YES];
528 }
529 else
530 {
531 wxLogTrace(wxTRACE_COCOA, wxT("Idle END"));
532 }
533}
534
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535#ifdef __WXDEBUG__
536void wxApp::OnAssert(const wxChar *file, int line, const wxChar* cond, const wxChar *msg)
537{
8898456d 538 m_isInAssert = true;
b93d8cc4 539 wxAppBase::OnAssert(file, line, cond, msg);
8898456d 540 m_isInAssert = false;
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541}
542#endif // __WXDEBUG__
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543
544/* A note about Cocoa's event loops vs. run loops:
545
546 It's important to understand that Cocoa has a two-level event loop. The
547 outer level is run by NSApplication and can only ever happen on the main
548 thread. The nextEventMatchingMask:untilDate:inMode:dequeue: method returns
549 the next event which is then given to sendEvent: to send it. These
550 methods are defined in NSApplication and are thus part of AppKit.
551
552 Events (NSEvent) are only sent due to actual user actions like clicking
553 the mouse or moving the mouse or pressing a key and so on. There are no
554 paint events; there are no timer events; there are no socket events; there
555 are no idle events.
556
557 All of those types of "events" have nothing to do with the GUI at all.
558 That is why Cocoa's AppKit doesn't implement them. Instead, they are
559 implemented in Foundation's NSRunLoop which on OS X uses CFRunLoop
560 to do the actual work.
561
562 How NSApplication uses NSRunLoop is rather interesting. Basically, it
563 interacts with NSRunLoop only from within the nextEventMatchingMask
564 method. It passes its inMode: argument almost directly to NSRunLoop
565 and thus CFRunLoop. The run loop then runs (e.g. loops) until it
566 is told to exit. The run loop calls the callout functions directly.
567 From within those callout functions the run loop is considered to
568 be running. Presumably, the AppKit installs a run loop source to
569 receive messages from the window server over the mach port (like a
570 socket). For some messages (e.g. need to paint) the AppKit will
571 call application code like drawRect: without exiting the run loop.
572 For other messages (ones that can be encapsulated in an NSEvent)
573 the AppKit tells the run loop to exit which returns control to
574 the nextEventMatchingMask method which then returns the NSEvent
575 object. It's important to note that once the runloop has exited
576 it is no longer considered running and thus if you ask it which
577 mode it is running in it will return nil.
578
579 When manually pumping the event loop care should be taken to
580 tell it to run in the correct mode. For instance, if you are
581 using it to run a modal dialog then you want to run it in
582 the modal panel run loop mode. AppKit presumably has sources
583 or timers or observers that specifically don't listen on this
584 mode. Another interesting mode is the connection reply mode.
585 This allows Cocoa to wait for a response from a distributed
586 objects message without firing off user code that may result
587 in a DO call being made thus recursing. So basically, the
588 mode is a way for Cocoa to attempt to avoid run loop recursion
589 but to allow it under certain circumstances.
590 */
591