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Source code for kivy.support


Activate other frameworks/toolkits inside the kivy event loop.


__all__ = ('install_gobject_iteration', 'install_twisted_reactor',
           'uninstall_twisted_reactor', 'install_android')

[docs]def install_gobject_iteration(): '''Import and install gobject context iteration inside our event loop. This is used as soon as gobject is used (like gstreamer). ''' from kivy.clock import Clock try: from gi.repository import GObject as gobject except ImportError: import gobject if hasattr(gobject, '_gobject_already_installed'): # already installed, don't do it twice. return gobject._gobject_already_installed = True # get gobject mainloop / context loop = gobject.MainLoop() gobject.threads_init() context = loop.get_context() # schedule the iteration each frame def _gobject_iteration(*largs): # XXX we need to loop over context here, otherwise, we might have a lag loop = 0 while context.pending() and loop < 10: context.iteration(False) loop += 1 Clock.schedule_interval(_gobject_iteration, 0)
# ----------------------------------------------------------------------------- # Android support # ----------------------------------------------------------------------------- g_android_redraw_count = 0 _redraw_event = None def _android_ask_redraw(*largs): # after wakeup, we need to redraw more than once, otherwise we get a # black screen global g_android_redraw_count from kivy.core.window import Window Window.canvas.ask_update() g_android_redraw_count -= 1 if g_android_redraw_count < 0: return False
[docs]def install_android(): '''Install hooks for the android platform. * Automatically sleep when the device is paused. * Automatically kill the application when the return key is pressed. ''' try: import android except ImportError: print('Android lib is missing, cannot install android hooks') return from kivy.clock import Clock from kivy.logger import Logger import pygame Logger.info('Support: Android install hooks') # Init the library android.init() android.map_key(android.KEYCODE_MENU, pygame.K_MENU) android.map_key(android.KEYCODE_BACK, pygame.K_ESCAPE) # Check if android should be paused or not. # If pause is requested, just leave the app. def android_check_pause(*largs): # do nothing until android asks for it. if not android.check_pause(): return from kivy.app import App from kivy.base import stopTouchApp from kivy.logger import Logger from kivy.core.window import Window global g_android_redraw_count, _redraw_event # try to get the current running application Logger.info('Android: Must go into sleep mode, check the app') app = App.get_running_app() # no running application, stop our loop. if app is None: Logger.info('Android: No app running, stop everything.') stopTouchApp() return # try to go to pause mode if app.dispatch('on_pause'): Logger.info('Android: App paused, now wait for resume.') # app goes in pause mode, wait. android.wait_for_resume() # is it a stop or resume ? if android.check_stop(): # app must stop Logger.info('Android: Android wants to close our app.') stopTouchApp() else: # app resuming now ! Logger.info('Android: Android has resumed, resume the app.') app.dispatch('on_resume') Window.canvas.ask_update() g_android_redraw_count = 25 # 5 frames/seconds for 5 seconds if _redraw_event is None: _redraw_event = Clock.schedule_interval( _android_ask_redraw, 1 / 5) else: _redraw_event.cancel() _redraw_event() Logger.info('Android: App resume completed.') # app doesn't support pause mode, just stop it. else: Logger.info('Android: App doesn\'t support pause mode, stop.') stopTouchApp() Clock.schedule_interval(android_check_pause, 0)
_twisted_reactor_stopper = None _twisted_reactor_work = None
[docs]def install_twisted_reactor(**kwargs): '''Installs a threaded twisted reactor, which will schedule one reactor iteration before the next frame only when twisted needs to do some work. Any arguments or keyword arguments passed to this function will be passed on the the threadedselect reactors interleave function. These are the arguments one would usually pass to twisted's reactor.startRunning. Unlike the default twisted reactor, the installed reactor will not handle any signals unless you set the 'installSignalHandlers' keyword argument to 1 explicitly. This is done to allow kivy to handle the signals as usual unless you specifically want the twisted reactor to handle the signals (e.g. SIGINT). .. note:: Twisted is not included in iOS build by default. To use it on iOS, put the twisted distribution (and zope.interface dependency) in your application directory. ''' import twisted # prevent installing more than once if hasattr(twisted, '_kivy_twisted_reactor_installed'): return twisted._kivy_twisted_reactor_installed = True # don't let twisted handle signals, unless specifically requested kwargs.setdefault('installSignalHandlers', 0) # install threaded-select reactor, to use with own event loop from twisted.internet import _threadedselect _threadedselect.install() # now we can import twisted reactor as usual from twisted.internet import reactor from twisted.internet.error import ReactorNotRunning from collections import deque from kivy.base import EventLoop from kivy.logger import Logger from kivy.clock import Clock # will hold callbacks to twisted callbacks q = deque() # twisted will call the wake function when it needs to do work def reactor_wake(twisted_loop_next): '''Wakeup the twisted reactor to start processing the task queue ''' Logger.trace("Support: twisted wakeup call to schedule task") q.append(twisted_loop_next) # called every frame, to process the reactors work in main thread def reactor_work(*args): '''Process the twisted reactor task queue ''' Logger.trace("Support: processing twisted task queue") while len(q): q.popleft()() global _twisted_reactor_work _twisted_reactor_work = reactor_work # start the reactor, by telling twisted how to wake, and process def reactor_start(*args): '''Start the twisted reactor main loop ''' Logger.info("Support: Starting twisted reactor") reactor.interleave(reactor_wake, **kwargs) Clock.schedule_interval(reactor_work, 0) # make sure twisted reactor is shutdown if eventloop exists def reactor_stop(*args): '''Shutdown the twisted reactor main loop ''' if reactor.threadpool: Logger.info("Support: Stopping twisted threads") reactor.threadpool.stop() Logger.info("Support: Shutting down twisted reactor") reactor._mainLoopShutdown() try: reactor.stop() except ReactorNotRunning: pass import sys sys.modules.pop('twisted.internet.reactor', None) global _twisted_reactor_stopper _twisted_reactor_stopper = reactor_stop # start and stop the reactor along with kivy EventLoop Clock.schedule_once(reactor_start, 0) EventLoop.bind(on_stop=reactor_stop)
[docs]def uninstall_twisted_reactor(): '''Uninstalls the Kivy's threaded Twisted Reactor. No more Twisted tasks will run after this got called. Use this to clean the `twisted.internet.reactor` . .. versionadded:: 1.9.0 ''' import twisted # prevent uninstalling more than once if not hasattr(twisted, '_kivy_twisted_reactor_installed'): return from kivy.base import EventLoop global _twisted_reactor_stopper _twisted_reactor_stopper() EventLoop.unbind(on_stop=_twisted_reactor_stopper) del twisted._kivy_twisted_reactor_installed