"""AppKit helpers.
Exported functions:
* runEventLoop - run NSApplicationMain in a safer way
* runConsoleEventLoop - run NSRunLoop.run() in a stoppable manner
* stopEventLoop - stops the event loop or terminates the application
* endSheetMethod - set correct signature for NSSheet callbacks
* callAfter - call a function on the main thread (async)
* callLater - call a function on the main thread after a delay (async)
"""
__all__ = ( 'runEventLoop', 'runConsoleEventLoop', 'stopEventLoop', 'endSheetMethod', 'callAfter', 'callLater' )
from AppKit import *
from Foundation import *
import os
import sys
import traceback
import objc
class PyObjCAppHelperCaller(NSObject):
def initWithArgs_(self, args):
self = self.init()
self.args = args
return self
def callAfter_(self, sender):
self.performSelectorOnMainThread_withObject_waitUntilDone_(
self.call_, self.args, False)
def callLater_(self, delay):
self.performSelector_withObject_afterDelay_(
self.callAfter_, None, delay)
def call_(self, (func, args, kwargs)):
func(*args, **kwargs)
def callAfter(func, *args, **kwargs):
"""call a function on the main thread (async)"""
pool = NSAutoreleasePool.alloc().init()
obj = PyObjCAppHelperCaller.alloc().initWithArgs_((func, args, kwargs))
obj.callAfter_(None)
del obj
del pool
def callLater(delay, func, *args, **kwargs):
"""call a function on the main thread after a delay (async)"""
pool = NSAutoreleasePool.alloc().init()
obj = PyObjCAppHelperCaller.alloc().initWithArgs_((func, args, kwargs))
obj.callLater_(delay)
del obj
del pool
class PyObjCAppHelperApplicationActivator(NSObject):
def activateNow_(self, aNotification):
NSApp().activateIgnoringOtherApps_(True)
class PyObjCAppHelperRunLoopStopper(NSObject):
singletons = {}
def currentRunLoopStopper(cls):
runLoop = NSRunLoop.currentRunLoop()
return cls.singletons.get(runLoop)
currentRunLoopStopper = classmethod(currentRunLoopStopper)
def init(self):
self = super(PyObjCAppHelperRunLoopStopper, self).init()
self.shouldStop = False
return self
def shouldRun(self):
return not self.shouldStop
def addRunLoopStopper_toRunLoop_(cls, runLoopStopper, runLoop):
if runLoop in cls.singletons:
raise ValueError, "Stopper already registered for this runLoop"
cls.singletons[runLoop] = runLoopStopper
addRunLoopStopper_toRunLoop_ = classmethod(addRunLoopStopper_toRunLoop_)
def removeRunLoopStopperFromRunLoop_(cls, runLoop):
if runLoop not in cls.singletons:
raise ValueError, "Stopper not registered for this runLoop"
del cls.singletons[runLoop]
removeRunLoopStopperFromRunLoop_ = classmethod(removeRunLoopStopperFromRunLoop_)
def stop(self):
self.shouldStop = True
# this should go away when/if runEventLoop uses
# runLoop iteration
if NSApp() is not None:
NSApp().terminate_(self)
def performStop_(self, sender):
self.stop()
def stopEventLoop():
"""
Stop the current event loop if possible
returns True if it expects that it was successful, False otherwise
"""
stopper = PyObjCAppHelperRunLoopStopper.currentRunLoopStopper()
if stopper is None:
if NSApp() is not None:
NSApp().terminate_(None)
return True
return False
NSTimer.scheduledTimerWithTimeInterval_target_selector_userInfo_repeats_(
0.0,
stopper,
'performStop:',
None,
False)
return True
def endSheetMethod(meth):
"""
Return a selector that can be used as the delegate callback for
sheet methods
"""
return objc.selector(meth, signature='v@:@ii')
def unexpectedErrorAlertPanel():
exceptionInfo = traceback.format_exception_only(
*sys.exc_info()[:2])[0].strip()
return NSRunAlertPanel("An unexpected error has occurred",
"%@",
"Continue", "Quit", None, "(%s)" % exceptionInfo)
def unexpectedErrorAlertPdb():
import pdb
traceback.print_exc()
pdb.post_mortem(sys.exc_info()[2])
return True
def machInterrupt(signum):
stopper = PyObjCAppHelperRunLoopStopper.currentRunLoopStopper()
if stopper is not None:
stopper.stop()
elif NSApp() is not None:
NSApp().terminate_(None)
else:
import os
os._exit(1)
def installMachInterrupt():
try:
import signal
from PyObjCTools import MachSignals
except:
return
MachSignals.signal(signal.SIGINT, machInterrupt)
def runConsoleEventLoop(argv=None, installInterrupt=False, mode=NSDefaultRunLoopMode):
if argv is None:
argv = sys.argv
if installInterrupt:
installMachInterrupt()
runLoop = NSRunLoop.currentRunLoop()
stopper = PyObjCAppHelperRunLoopStopper.alloc().init()
PyObjCAppHelperRunLoopStopper.addRunLoopStopper_toRunLoop_(stopper, runLoop)
try:
while stopper.shouldRun():
nextfire = runLoop.limitDateForMode_(mode)
if not stopper.shouldRun():
break
if not runLoop.runMode_beforeDate_(mode, nextfire):
stopper.stop()
finally:
PyObjCAppHelperRunLoopStopper.removeRunLoopStopperFromRunLoop_(runLoop)
RAISETHESE = (SystemExit, MemoryError, KeyboardInterrupt)
def runEventLoop(argv=None, unexpectedErrorAlert=None, installInterrupt=None, pdb=None, main=NSApplicationMain):
"""Run the event loop, ask the user if we should continue if an
exception is caught. Use this function instead of NSApplicationMain().
"""
if argv is None:
argv = sys.argv
if pdb is None:
pdb = 'USE_PDB' in os.environ
if pdb:
from PyObjCTools import Debugging
Debugging.installVerboseExceptionHandler()
# bring it to the front, starting from terminal
# often won't
activator = PyObjCAppHelperApplicationActivator.alloc().init()
NSNotificationCenter.defaultCenter().addObserver_selector_name_object_(
activator,
'activateNow:',
NSApplicationDidFinishLaunchingNotification,
None,
)
else:
Debugging = None
if installInterrupt is None and pdb:
installInterrupt = True
if unexpectedErrorAlert is None:
if pdb:
unexpectedErrorAlert = unexpectedErrorAlertPdb
else:
unexpectedErrorAlert = unexpectedErrorAlertPanel
runLoop = NSRunLoop.currentRunLoop()
stopper = PyObjCAppHelperRunLoopStopper.alloc().init()
PyObjCAppHelperRunLoopStopper.addRunLoopStopper_toRunLoop_(stopper, runLoop)
firstRun = NSApp() is None
try:
while stopper.shouldRun():
try:
if firstRun:
firstRun = False
if installInterrupt:
installMachInterrupt()
main(argv)
else:
NSApp().run()
except RAISETHESE:
traceback.print_exc()
break
except:
exctype, e, tb = sys.exc_info()
objc_exception = False
if isinstance(e, objc.error):
NSLog("%@", unicode(str(e), 'utf-8', 'replace'))
elif not unexpectedErrorAlert():
NSLog("%@", u"An exception has occured:")
traceback.print_exc()
sys.exit(0)
else:
NSLog("%@", u"An exception has occured:")
traceback.print_exc()
else:
break
finally:
if Debugging is not None:
Debugging.removeExceptionHandler()
PyObjCAppHelperRunLoopStopper.removeRunLoopStopperFromRunLoop_(runLoop)
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