registryconnecteddynamicclient.py

#!/usr/bin/env python


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## Copyright (C) 2017 Ford Motor Company
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import sys

from PyQt5.QtCore import pyqtSignal, pyqtSlot, QCoreApplication, QObject, QUrl
from PyQt5.QtRemoteObjects import QRemoteObjectNode


class DynamicClient(QObject):

    # This signal is connected with server_slot() slot of the source object and
    # echoes back the switch state received from the source.
    echoSwitchState = pyqtSignal(bool)

    def __init__(self, replica, parent=None):
        super().__init__(parent)

        self._replica = replica
        self._clientSwitchState = False

        replica.initialized.connect(self.initConnection)

    @pyqtSlot(bool)
    def recSwitchState(self, value):
        self._clientSwitchState = self._replica.property('currState')

        print("Received source state", value, self._clientSwitchState)

        # Emit the signal to echo the received state back to the server.
        self.echoSwitchState.emit(self._clientSwitchState)

    @pyqtSlot()
    def initConnection(self):
        # Connect the replica source signal currStateChanged() with the
        # client's recSwitchState() slot to receive the source's current state.
        self._replica.currStateChanged.connect(self.recSwitchState)

        # Connect the client's echoSwitchState() signal with replica's
        # server_slot() to echo back the received state.
        self.echoSwitchState.connect(self._replica.server_slot)


if __name__ == '__main__':

    app = QCoreApplication(sys.argv)

    # Create the remote object node.
    repNode = QRemoteObjectNode(QUrl('local:registry'))

    # Acquire a replica of the source from the host node.
    replica = repNode.acquireDynamic('SimpleSwitch')

    # Create the client switch object and pass the replica to it.
    rswitch = DynamicClient(replica)

    sys.exit(app.exec_())