/////////////////////////////////////////////////////////////////////////////
-// Name: cocoa/app.mm
+// Name: src/cocoa/app.mm
// Purpose: wxApp
// Author: David Elliott
// Modified by:
// Created: 2002/11/27
// RCS-ID: $Id$
// Copyright: (c) David Elliott
+// Software 2000 Ltd.
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#include "wx/wxprec.h"
+
+#include "wx/app.h"
+
#ifndef WX_PRECOMP
- #include "wx/defs.h"
- #include "wx/app.h"
- #include "wx/frame.h"
- #include "wx/dialog.h"
- #include "wx/dc.h"
#include "wx/intl.h"
#include "wx/log.h"
+ #include "wx/module.h"
#endif
-#include "wx/module.h"
-
-#include "wx/cocoa/ObjcPose.h"
+#include "wx/cocoa/ObjcRef.h"
#include "wx/cocoa/autorelease.h"
#include "wx/cocoa/mbarman.h"
+#include "wx/cocoa/NSApplication.h"
-#if wxUSE_WX_RESOURCES
-# include "wx/resource.h"
-#endif
+#include "wx/cocoa/dc.h"
#import <AppKit/NSApplication.h>
#import <Foundation/NSRunLoop.h>
-#import <Foundation/NSArray.h>
-#import <Foundation/NSAutoreleasePool.h>
#import <Foundation/NSThread.h>
#import <AppKit/NSEvent.h>
+#import <Foundation/NSString.h>
+#import <Foundation/NSNotification.h>
+#import <AppKit/NSCell.h>
+
+bool wxApp::sm_isEmbedded = false; // Normally we're not a plugin
+
+// wxNSApplicationObserver singleton.
+static wxObjcAutoRefFromAlloc<wxNSApplicationObserver*> sg_cocoaAppObserver = [[WX_GET_OBJC_CLASS(wxNSApplicationObserver) alloc] init];
// ========================================================================
-// wxPoseAsInitializer
+// wxNSApplicationDelegate
// ========================================================================
-wxPoseAsInitializer *wxPoseAsInitializer::sm_first = NULL;
+@implementation wxNSApplicationDelegate : NSObject
+
+// NOTE: Terminate means that the event loop does NOT return and thus
+// cleanup code doesn't properly execute. Furthermore, wxWidgets has its
+// own exit on frame delete mechanism.
+- (BOOL)applicationShouldTerminateAfterLastWindowClosed:(NSApplication *)theApplication
+{
+ return NO;
+}
+
+@end // implementation wxNSApplicationDelegate : NSObject
+WX_IMPLEMENT_GET_OBJC_CLASS(wxNSApplicationDelegate,NSObject)
// ========================================================================
-// wxPoserNSApplication
+// wxNSApplicationObserver
// ========================================================================
-@interface wxPoserNSApplication : NSApplication
+@implementation wxNSApplicationObserver : NSObject
+
+- (void)applicationWillBecomeActive:(NSNotification *)notification
{
+ wxTheApp->CocoaDelegate_applicationWillBecomeActive();
}
-- (void)doIdle: (id)data;
-- (void)sendEvent: (NSEvent*)anEvent;
-- (BOOL)applicationShouldTerminateAfterLastWindowClosed:(NSApplication *)theApplication;
-@end // wxPoserNSApplication
-
-WX_IMPLEMENT_POSER(wxPoserNSApplication);
+- (void)applicationDidBecomeActive:(NSNotification *)notification
+{
+ wxTheApp->CocoaDelegate_applicationDidBecomeActive();
+}
-@implementation wxPoserNSApplication : NSApplication
+- (void)applicationWillResignActive:(NSNotification *)notification
+{
+ wxTheApp->CocoaDelegate_applicationWillResignActive();
+}
-- (void)doIdle: (id)data
+- (void)applicationDidResignActive:(NSNotification *)notification
{
- wxASSERT(wxTheApp);
- wxASSERT(wxMenuBarManager::GetInstance());
- wxMenuBarManager::GetInstance()->CocoaInternalIdle();
- wxLogDebug("doIdle called");
-#ifdef __WXDEBUG__
- if(wxTheApp->IsInAssert())
- {
- wxLogDebug("Idle events ignored durring assertion dialog");
- }
- else
-#endif
- {
- NSRunLoop *rl = [NSRunLoop currentRunLoop];
- // runMode: beforeDate returns YES if something was done
- while(wxTheApp->ProcessIdle()) // FIXME: AND NO EVENTS ARE PENDING
- {
- wxLogDebug("Looping for idle events");
- #if 1
- if( [rl runMode:[rl currentMode] beforeDate:[NSDate distantPast]])
- {
- wxLogDebug("Found actual work to do");
- break;
- }
- #endif
- }
- }
- wxLogDebug("Idle processing complete, requesting next idle event");
- // Add ourself back into the run loop (on next event) if necessary
- wxTheApp->CocoaRequestIdle();
+ wxTheApp->CocoaDelegate_applicationDidResignActive();
}
-- (void)sendEvent: (NSEvent*)anEvent
+- (void)applicationWillUpdate:(NSNotification *)notification;
{
- wxLogDebug("SendEvent");
- wxTheApp->CocoaInstallRequestedIdleHandler();
- [super sendEvent: anEvent];
+ wxTheApp->CocoaDelegate_applicationWillUpdate();
}
-- (BOOL)applicationShouldTerminateAfterLastWindowClosed:(NSApplication *)theApplication
+- (void)controlTintChanged:(NSNotification *)notification
{
- BOOL ret = wxTheApp->GetExitOnFrameDelete();
- wxLogDebug("applicationShouldTermintaeAfterLastWindowClosed=%d",ret);
- return ret;
+ wxLogDebug(wxT("TODO: send EVT_SYS_COLOUR_CHANGED as appropriate"));
}
-@end // wxPoserNSApplication
+@end // implementation wxNSApplicationObserver : NSObject
+WX_IMPLEMENT_GET_OBJC_CLASS(wxNSApplicationObserver,NSObject)
// ========================================================================
// wxApp
// wxApp Static member initialization
// ----------------------------------------------------------------------------
IMPLEMENT_DYNAMIC_CLASS(wxApp, wxEvtHandler)
-BEGIN_EVENT_TABLE(wxApp, wxEvtHandler)
- EVT_IDLE(wxAppBase::OnIdle)
-// EVT_END_SESSION(wxApp::OnEndSession)
-// EVT_QUERY_END_SESSION(wxApp::OnQueryEndSession)
-END_EVENT_TABLE()
// ----------------------------------------------------------------------------
// wxApp initialization/cleanup
// application (otherwise applications would need to handle it)
if ( argc > 1 )
{
- static const wxChar *ARG_PSN = _T("-psn_");
- if ( wxStrncmp(argv[1], ARG_PSN, sizeof(ARG_PSN) - 1) == 0 )
+ static const wxChar *ARG_PSN = wxT("-psn_");
+ if ( wxStrncmp(argv[1], ARG_PSN, wxStrlen(ARG_PSN)) == 0 )
{
// remove this argument
- memmove(argv, argv + 1, argc--);
+ --argc;
+ memmove(argv + 1, argv + 2, argc * sizeof(wxChar *));
}
}
- // Posing must be completed before any instances of the Objective-C
- // classes being posed as are created.
- wxPoseAsInitializer::InitializePosers();
+ /*
+ Cocoa supports -Key value options which set the user defaults key "Key"
+ to the value "value" Some of them are very handy for debugging like
+ -NSShowAllViews YES. Cocoa picks these up from the real argv so
+ our removal of them from the wx copy of it does not affect Cocoa's
+ ability to see them.
+
+ We basically just assume that any "-NS" option and its following
+ argument needs to be removed from argv. We hope that user code does
+ not expect to see -NS options and indeed it's probably a safe bet
+ since most user code accepting options is probably using the
+ double-dash GNU-style syntax.
+ */
+ for(int i=1; i < argc; ++i)
+ {
+ static const wxChar *ARG_NS = wxT("-NS");
+ static const int ARG_NS_LEN = wxStrlen(ARG_NS);
+ if( wxStrncmp(argv[i], ARG_NS, ARG_NS_LEN) == 0 )
+ {
+ // Only eat this option if it has an argument
+ if( (i + 1) < argc )
+ {
+ argc -= 2;
+ memmove(argv + i, argv + i + 2, argc * sizeof(wxChar*));
+ // drop back one position so the next run through the loop
+ // reprocesses the argument at our current index.
+ --i;
+ }
+ }
+ }
return wxAppBase::Initialize(argc, argv);
}
void wxApp::CleanUp()
{
- wxDC::CocoaShutdownTextSystem();
+ wxAutoNSAutoreleasePool pool;
+
+ wxCocoaDCImpl::CocoaShutdownTextSystem();
wxMenuBarManager::DestroyInstance();
+ [[NSNotificationCenter defaultCenter] removeObserver:sg_cocoaAppObserver];
+ if(!sm_isEmbedded)
+ {
+ [m_cocoaApp setDelegate:nil];
+ [m_cocoaAppDelegate release];
+ m_cocoaAppDelegate = NULL;
+ }
+
wxAppBase::CleanUp();
}
{
m_topWindow = NULL;
- m_isIdle = true;
-#if WXWIN_COMPATIBILITY_2_2
- m_wantDebugOutput = TRUE;
-#endif
-#ifdef __WXDEBUG__
- m_isInAssert = FALSE;
-#endif // __WXDEBUG__
-
argc = 0;
+#if !wxUSE_UNICODE
argv = NULL;
+#endif
m_cocoaApp = NULL;
+ m_cocoaAppDelegate = NULL;
}
-void wxApp::CocoaInstallIdleHandler()
+void wxApp::CocoaDelegate_applicationWillBecomeActive()
+{
+}
+
+void wxApp::CocoaDelegate_applicationDidBecomeActive()
+{
+}
+
+void wxApp::CocoaDelegate_applicationWillResignActive()
+{
+ wxTopLevelWindowCocoa::DeactivatePendingWindow();
+}
+
+void wxApp::CocoaDelegate_applicationDidResignActive()
{
- // If we're not the main thread, don't install the idle handler
- if(m_cocoaMainThread != [NSThread currentThread])
- {
- wxLogDebug("Attempt to install idle handler from secondary thread");
- return;
- }
- // If we're supposed to be stopping, don't add more idle events
- if(![m_cocoaApp isRunning])
- return;
- wxLogDebug("wxApp::CocoaInstallIdleHandler");
- m_isIdle = false;
- // Call doIdle for EVERYTHING dammit
-// We'd need Foundation/NSConnection.h for this next constant, do we need it?
- [[ NSRunLoop currentRunLoop ] performSelector:@selector(doIdle:) target:m_cocoaApp argument:NULL order:0 modes:[NSArray arrayWithObjects:NSDefaultRunLoopMode, /* NSConnectionReplyRunLoopMode,*/ NSModalPanelRunLoopMode, /**/NSEventTrackingRunLoopMode,/**/ nil] ];
}
bool wxApp::OnInitGui()
{
wxAutoNSAutoreleasePool pool;
if(!wxAppBase::OnInitGui())
- return FALSE;
+ return false;
// Create the app using the sharedApplication method
m_cocoaApp = [NSApplication sharedApplication];
- wxMenuBarManager::CreateInstance();
+ if(!sm_isEmbedded)
+ {
+ // Enable response to application delegate messages
+ m_cocoaAppDelegate = [[WX_GET_OBJC_CLASS(wxNSApplicationDelegate) alloc] init];
+ [m_cocoaApp setDelegate:m_cocoaAppDelegate];
+ }
+
+ // Enable response to "delegate" messages on the notification observer
+ [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
+ selector:@selector(applicationWillBecomeActive:)
+ name:NSApplicationWillBecomeActiveNotification object:nil];
+
+ [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
+ selector:@selector(applicationDidBecomeActive:)
+ name:NSApplicationDidBecomeActiveNotification object:nil];
+
+ [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
+ selector:@selector(applicationWillResignActive:)
+ name:NSApplicationWillResignActiveNotification object:nil];
+
+ [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
+ selector:@selector(applicationDidResignActive:)
+ name:NSApplicationDidResignActiveNotification object:nil];
+
+ [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
+ selector:@selector(applicationWillUpdate:)
+ name:NSApplicationWillUpdateNotification object:nil];
+
+ // Enable response to system notifications
+ [[NSNotificationCenter defaultCenter] addObserver:sg_cocoaAppObserver
+ selector:@selector(controlTintChanged:)
+ name:NSControlTintDidChangeNotification object:nil];
+
+ if(!sm_isEmbedded)
+ wxMenuBarManager::CreateInstance();
+
+ wxCocoaDCImpl::CocoaInitializeTextSystem();
+ return true;
+}
- wxDC::CocoaInitializeTextSystem();
-// [ m_cocoaApp setDelegate:m_cocoaApp ];
- #if 0
- wxLogDebug("Just for kicks");
- [ m_cocoaApp performSelector:@selector(doIdle:) withObject:NULL ];
- wxLogDebug("okay.. done now");
- #endif
- return TRUE;
+wxApp::~wxApp()
+{
+ if(m_cfRunLoopIdleObserver != NULL)
+ {
+ // Invalidate the observer which also removes it from the run loop.
+ CFRunLoopObserverInvalidate(m_cfRunLoopIdleObserver);
+ // Release the ref as we don't need it anymore.
+ m_cfRunLoopIdleObserver.reset();
+ }
}
bool wxApp::CallOnInit()
bool wxApp::OnInit()
{
if(!wxAppBase::OnInit())
- return FALSE;
+ return false;
- return TRUE;
+ return true;
}
void wxApp::Exit()
wxAppConsole::Exit();
}
-int wxApp::MainLoop()
+void wxApp::WakeUpIdle()
{
- [m_cocoaApp run];
- return 0;
+ /* When called from the main thread the NSAutoreleasePool managed by
+ the [NSApplication run] method would ordinarily be in place and so
+ one would think a pool here would be unnecessary.
+
+ However, when called from a different thread there is usually no
+ NSAutoreleasePool in place because wxThread has no knowledge of
+ wxCocoa. The pool here is generally only ever going to contain
+ the NSEvent we create with the factory method. As soon as we add
+ it to the main event queue with postEvent:atStart: it is retained
+ and so safe for our pool to release.
+ */
+ wxAutoNSAutoreleasePool pool;
+ /* NOTE: This is a little heavy handed. What this does is cause an
+ AppKit NSEvent to be added to NSApplication's queue (which is always
+ on the main thread). This will cause the main thread runloop to
+ exit which returns control to nextEventMatchingMask which returns
+ the event which is then sent with sendEvent: and essentially dropped
+ since it's not for a window (windowNumber 0) and NSApplication
+ certainly doesn't understand it.
+
+ With the exception of wxEventLoop::Exit which uses us to cause the
+ runloop to exit and return to the NSApplication event loop, most
+ callers only need wx idle to happen, or more specifically only really
+ need to ensure that ProcessPendingEvents is called which is currently
+ done without exiting the runloop.
+
+ Be careful if you decide to change the implementation of this method
+ as wxEventLoop::Exit depends on the current behavior.
+ */
+ [m_cocoaApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
+ location:NSZeroPoint modifierFlags:NSAnyEventMask
+ timestamp:0 windowNumber:0 context:nil
+ subtype:0 data1:0 data2:0] atStart:NO];
}
-void wxApp::ExitMainLoop()
+extern "C" static void ObserveMainRunLoopBeforeWaiting(CFRunLoopObserverRef observer, CFRunLoopActivity activity, void *info);
+extern "C" static void ObserveMainRunLoopBeforeWaiting(CFRunLoopObserverRef observer, CFRunLoopActivity activity, void *info)
{
- wxLogDebug("wxApp::ExitMailLoop m_isIdle=%d, isRunning=%d",(int)m_isIdle,(int)[m_cocoaApp isRunning]);
-// CocoaInstallRequestedIdleHandler();
-// if(m_isIdle)
-// [[ NSRunLoop currentRunLoop ] performSelector:@selector(doIdle:) target:m_cocoaApp argument:NULL order:0 modes:[NSArray arrayWithObjects:NSDefaultRunLoopMode, /* NSConnectionReplyRunLoopMode, NSModalPanelRunLoopMode, NSEventTrackingRunLoopMode,*/ nil] ];
-// actually.. we WANT the idle event
-// or not
+ static_cast<wxApp*>(info)->CF_ObserveMainRunLoopBeforeWaiting(observer, activity);
+}
+
#if 0
- if(!m_isIdle)
- [[ NSRunLoop currentRunLoop ] cancelPerformSelector:@selector(doIdle:) target:m_cocoaApp argument:NULL];
+static int sg_cApplicationWillUpdate = 0;
#endif
- [m_cocoaApp stop: m_cocoaApp];
-}
-// Is a message/event pending?
-bool wxApp::Pending()
+/*!
+ Invoked from the applicationWillUpdate notification observer. See the
+ NSApplication documentation for the official statement on when this
+ will be called. Since it can be hard to understand for a Cocoa newbie
+ I'll try to explain it here as it relates to wxCocoa.
+
+ Basically, we get called from within nextEventMatchingMask if and only
+ if any user code told the application to send the update notification
+ (sort of like a request for idle events). However, unlike wx idle events,
+ this notification is sent quite often, nearly every time through the loop
+ because nearly every control tells the application to send it.
+
+ Because wx idle events are only supposed to be sent when the event loop
+ is about to block we instead schedule a function to be called just
+ before the run loop waits and send the idle events from there.
+
+ It also has the desirable effect of only sending the wx idle events when
+ the event loop is actualy going to block. If the event loop is being
+ pumped manualy (e.g. like a PeekMessage) then the kCFRunLoopBeforeWaiting
+ observer never fires. Our Yield() method depends on this because sending
+ idle events from within Yield would be bad.
+
+ Normally you might think that we could just set the observer up once and
+ leave it attached. However, this is problematic because our run loop
+ observer calls user code (the idle handlers) which can actually display
+ modal dialogs. Displaying a modal dialog causes reentry of the event
+ loop, usually in a different run loop mode than the main loop (e.g. in
+ modal-dialog mode instead of default mode). Because we only register the
+ observer with the run loop mode at the time of this call, it won't be
+ called from a modal loop.
+
+ We want it to be called and thus we need a new observer.
+ */
+void wxApp::CocoaDelegate_applicationWillUpdate()
{
- return 0;
+ wxLogTrace(wxTRACE_COCOA,wxT("applicationWillUpdate"));
+
+// CFRunLoopRef cfRunLoop = [[NSRunLoop currentRunLoop] getCFRunLoop];
+ CFRunLoopRef cfRunLoop = CFRunLoopGetCurrent();
+ wxCFRef<CFStringRef> cfRunLoopMode(CFRunLoopCopyCurrentMode(cfRunLoop));
+
+ /* If we have an observer and that observer is for the wrong run loop
+ mode then invalidate it and release it.
+ */
+ if(m_cfRunLoopIdleObserver != NULL && m_cfObservedRunLoopMode != cfRunLoopMode)
+ {
+ CFRunLoopObserverInvalidate(m_cfRunLoopIdleObserver);
+ m_cfRunLoopIdleObserver.reset();
+ }
+#if 0
+ ++sg_cApplicationWillUpdate;
+#endif
+ /* This will be true either on the first call or when the above code has
+ invalidated and released the exisiting observer.
+ */
+ if(m_cfRunLoopIdleObserver == NULL)
+ {
+ // Enable idle event handling
+ CFRunLoopObserverContext observerContext =
+ { 0
+ , this
+ , NULL
+ , NULL
+ , NULL
+ };
+ /* NOTE: I can't recall why we don't just let the observer repeat
+ instead of invalidating itself each time it fires thus requiring
+ it to be recreated for each shot but there was if I remember
+ some good (but very obscure) reason for it.
+
+ On the other hand, I could be wrong so don't take that as gospel.
+ */
+ m_cfRunLoopIdleObserver.reset(CFRunLoopObserverCreate(kCFAllocatorDefault, kCFRunLoopBeforeWaiting, /*repeats*/FALSE, /*priority*/0, ObserveMainRunLoopBeforeWaiting, &observerContext));
+ m_cfObservedRunLoopMode = cfRunLoopMode;
+ CFRunLoopAddObserver(cfRunLoop, m_cfRunLoopIdleObserver, m_cfObservedRunLoopMode);
+ }
}
-// Dispatch a message.
-bool wxApp::Dispatch()
+static inline bool FakeNeedMoreIdle()
{
- return true;
+#if 0
+// Return true on every 10th call.
+ static int idleCount = 0;
+ return ++idleCount % 10;
+#else
+ return false;
+#endif
}
-// Yield to other processes
-bool wxApp::Yield(bool onlyIfNeeded)
+/*!
+ Called by CFRunLoop just before waiting. This is the appropriate time to
+ send idle events. Unlike other ports, we don't peek the queue for events
+ and stop idling if there is one. Instead, if the user requests more idle
+ events we tell Cocoa to send us an applicationWillUpdate notification
+ which will cause our observer of that notification to tell CFRunLoop to
+ call us before waiting which will cause us to be fired again but only
+ after exhausting the event queue.
+
+ The reason we do it this way is that peeking for an event causes CFRunLoop
+ to reenter and fire off its timers, observers, and sources which we're
+ better off avoiding. Doing it this way, we basically let CFRunLoop do the
+ work of peeking for the next event which is much nicer.
+ */
+void wxApp::CF_ObserveMainRunLoopBeforeWaiting(CFRunLoopObserverRef observer, int activity)
{
- // MT-FIXME
- static bool s_inYield = false;
-
-#if wxUSE_LOG
- // disable log flushing from here because a call to wxYield() shouldn't
- // normally result in message boxes popping up &c
- wxLog::Suspend();
-#endif // wxUSE_LOG
-
- if (s_inYield)
+ // Ensure that CocoaDelegate_applicationWillUpdate will recreate us.
+ // We've already been invalidated by CFRunLoop because we are one-shot.
+ m_cfRunLoopIdleObserver.reset();
+#if 0
+ wxLogTrace(wxTRACE_COCOA,wxT("Idle BEGIN (%d)"), sg_cApplicationWillUpdate);
+ sg_cApplicationWillUpdate = 0;
+#else
+ wxLogTrace(wxTRACE_COCOA,wxT("Idle BEGIN"));
+#endif
+ if( ProcessIdle() || FakeNeedMoreIdle() )
{
- if ( !onlyIfNeeded )
- {
- wxFAIL_MSG( wxT("wxYield called recursively" ) );
- }
-
- return false;
+ wxLogTrace(wxTRACE_COCOA, wxT("Idle REQUEST MORE"));
+ [NSApp setWindowsNeedUpdate:YES];
}
-
- s_inYield = true;
-
- // Run the event loop until it is out of events
- while(NSEvent *event = [GetNSApplication()
- nextEventMatchingMask:NSAnyEventMask
- untilDate:[NSDate distantPast]
- inMode:NSDefaultRunLoopMode
- dequeue: YES])
+ else
{
- [GetNSApplication() sendEvent: event];
+ wxLogTrace(wxTRACE_COCOA, wxT("Idle END"));
}
-
-#if wxUSE_LOG
- // let the logs be flashed again
- wxLog::Resume();
-#endif // wxUSE_LOG
-
- s_inYield = false;
-
- return true;
}
-#ifdef __WXDEBUG__
-void wxApp::OnAssert(const wxChar *file, int line, const wxChar* cond, const wxChar *msg)
-{
- m_isInAssert = TRUE;
- wxAppBase::OnAssert(file, line, cond, msg);
- m_isInAssert = FALSE;
-}
-#endif // __WXDEBUG__
+/* A note about Cocoa's event loops vs. run loops:
+
+ It's important to understand that Cocoa has a two-level event loop. The
+ outer level is run by NSApplication and can only ever happen on the main
+ thread. The nextEventMatchingMask:untilDate:inMode:dequeue: method returns
+ the next event which is then given to sendEvent: to send it. These
+ methods are defined in NSApplication and are thus part of AppKit.
+
+ Events (NSEvent) are only sent due to actual user actions like clicking
+ the mouse or moving the mouse or pressing a key and so on. There are no
+ paint events; there are no timer events; there are no socket events; there
+ are no idle events.
+
+ All of those types of "events" have nothing to do with the GUI at all.
+ That is why Cocoa's AppKit doesn't implement them. Instead, they are
+ implemented in Foundation's NSRunLoop which on OS X uses CFRunLoop
+ to do the actual work.
+
+ How NSApplication uses NSRunLoop is rather interesting. Basically, it
+ interacts with NSRunLoop only from within the nextEventMatchingMask
+ method. It passes its inMode: argument almost directly to NSRunLoop
+ and thus CFRunLoop. The run loop then runs (e.g. loops) until it
+ is told to exit. The run loop calls the callout functions directly.
+ From within those callout functions the run loop is considered to
+ be running. Presumably, the AppKit installs a run loop source to
+ receive messages from the window server over the mach port (like a
+ socket). For some messages (e.g. need to paint) the AppKit will
+ call application code like drawRect: without exiting the run loop.
+ For other messages (ones that can be encapsulated in an NSEvent)
+ the AppKit tells the run loop to exit which returns control to
+ the nextEventMatchingMask method which then returns the NSEvent
+ object. It's important to note that once the runloop has exited
+ it is no longer considered running and thus if you ask it which
+ mode it is running in it will return nil.
+
+ When manually pumping the event loop care should be taken to
+ tell it to run in the correct mode. For instance, if you are
+ using it to run a modal dialog then you want to run it in
+ the modal panel run loop mode. AppKit presumably has sources
+ or timers or observers that specifically don't listen on this
+ mode. Another interesting mode is the connection reply mode.
+ This allows Cocoa to wait for a response from a distributed
+ objects message without firing off user code that may result
+ in a DO call being made thus recursing. So basically, the
+ mode is a way for Cocoa to attempt to avoid run loop recursion
+ but to allow it under certain circumstances.
+ */
projects / wxWidgets.git / blobdiff