(self, on_change)
Enable notification of changes for this characteristic on the
        specified on_change callback.  on_change should be a function that takes
        one parameter which is the value (as a string of bytes) of the changed
        characteristic value.
Enable notification of changes for this characteristic on the
        specified on_change callback.  on_change should be a function that takes
        one parameter which is the value (as a string of bytes) of the changed
        characteristic value.
Enable notification of changes for this characteristic on the specified on_change callback . on_change should be a function that takes one parameter which is the value ( as a string of bytes ) of the changed characteristic value .
def start_notify(self, on_change):
        """Enable notification of changes for this characteristic on the
        specified on_change callback.  on_change should be a function that takes
        one parameter which is the value (as a string of bytes) of the changed
        characteristic value.
        """
        # Setup a closure to be the first step in handling the on change callback.
        # This closure will verify the characteristic is changed and pull out the
        # new value to pass to the user's on change callback.
        def characteristic_changed(iface, changed_props, invalidated_props):
            # Check that this change is for a GATT characteristic and it has a
            # new value.
            if iface != _CHARACTERISTIC_INTERFACE:
                return
            if 'Value' not in changed_props:
                return
            # Send the new value to the on_change callback.
            on_change(''.join(map(chr, changed_props['Value'])))
        # Hook up the property changed signal to call the closure above.
        self._props.connect_to_signal('PropertiesChanged', characteristic_changed)
        # Enable notifications for changes on the characteristic.
        self._characteristic.StartNotify()
def start_notify ( self , on_change ) : # Setup a closure to be the first step in handling the on change callback. # This closure will verify the characteristic is changed and pull out the # new value to pass to the user's on change callback. def characteristic_changed ( iface , changed_props , invalidated_props ) : # Check that this change is for a GATT characteristic and it has a # new value. if iface != _CHARACTERISTIC_INTERFACE : return if 'Value' not in changed_props : return # Send the new value to the on_change callback. on_change ( '' . join ( map ( chr , changed_props [ 'Value' ] ) ) ) # Hook up the property changed signal to call the closure above. self . _props . connect_to_signal ( 'PropertiesChanged' , characteristic_changed ) # Enable notifications for changes on the characteristic. self . _characteristic . StartNotify ( )