Callback example (with timer), for python

bindings/python/Callback functions/callbacks.py

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+from ctypes import c_int, c_ubyte, c_void_p, POINTER, string_at #imports allowing the use of our library
+from threading import Timer
+import time
+import platform
+
+#platform specific imports:
+if (platform.system() == 'Windows'):
+	#Windows
+	from ctypes import windll, WINFUNCTYPE
+	lib = windll.LoadLibrary('TelldusCore.dll') #import our library
+else:
+	#Linux
+	from ctypes import cdll, CFUNCTYPE
+	lib = cdll.LoadLibrary('libtelldus-core.so.2') #import our library
+
+timers = {} #timerlist
+
+def turnOn():
+	print "turning on"
+	lib.tdTurnOn(1)
+
+def turnOff():
+	print "turning off"
+	lib.tdTurnOff(1)
+	
+#function to be called when a device event occurs		
+def callbackfunction(deviceId, method, value, callbackId, context):
+	global timers
+	
+	print "callback!"
+
+	if (deviceId == 1):
+		# is turning on deviceId 1 here, so just return if events for that device are picked up
+		return
+		
+	t = 0
+	print "Received event for device %d" % (deviceId,)
+	if (deviceId in timers):
+		# a timer already exists for this device, it might be running so interrupt it
+		# Many devices (for example motion detectors) resends their messages many times to ensure that they
+		# are received correctly. In this example, we don't want to run the turnOn/turnOff methods every time, instead we
+		# start a timer, and run the method when the timer is finished. For every incoming event on this device, the timer
+		# is restarted.
+		t = timers[deviceId] 
+		t.cancel()
+	if (method == 1):
+		#on
+		t = Timer(0.5, turnOn) #start timer with 0.5 second delay (adjust the delay to suit your needs), then turn on
+	else:
+		#off
+		t = Timer(0.5, turnOff) #start timer with 0.5 second delay (adjust the delay to suit your needs), then turn off
+
+	t.start()
+	timers[deviceId] = t #put timer in list, to allow later cancellation
+
+#function to be called when device event occurs, even for unregistered devices
+def rawcallbackfunction(data, controllerId, callbackId, context):
+	print string_at(data)
+
+if (platform.system() == 'Windows'):
+	CMPFUNC = WINFUNCTYPE(c_void_p, c_int, c_int, POINTER(c_ubyte), c_int, c_void_p) #first is return type
+	CMPFUNCRAW = WINFUNCTYPE(c_void_p, POINTER(c_ubyte), c_int, c_int, c_void_p)
+else:
+	CMPFUNC = CFUNCTYPE(c_void_p, c_int, c_int, POINTER(c_ubyte), c_int, c_void_p)
+	CMPFUNCRAW = CFUNCTYPE(c_void_p, POINTER(c_ubyte), c_int, c_int, c_void_p)
+
+cmp_func = CMPFUNC(callbackfunction)
+cmp_funcraw = CMPFUNCRAW(rawcallbackfunction)
+
+lib.tdInit()
+lib.tdRegisterDeviceEvent(cmp_func, 0)
+#lib.tdRegisterRawDeviceEvent(cmp_funcraw, 0) #uncomment this, and comment out tdRegisterDeviceEvent, to see data for not registered devices
+
+print "Waiting for events..."
+while(1):
+	time.sleep(0.5) #don't exit