worker_thread.py

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from python_qt_binding.QtCore import QThread


class WorkerThread(QThread):
    """
    Run code in a separate thread, get notified upon completion and kill the thread synchronously.

    Convenience class built around a QThread
    """

    def __init__(self, run_callback, finished_callback=None):
        super(WorkerThread, self).__init__()
        self.run = run_callback
        self._finished_callback = finished_callback

    def start(self):
        # reconnect finished signal
        self.finished.connect(self._finished_handler)
        super(WorkerThread, self).start()

    def _finished_handler(self):
        # disconnect finished signal to avoid being called twice
        self.finished.disconnect(self._finished_handler)
        if self._finished_callback is not None:
            self._finished_callback()

    def kill(self):
        if self.isRunning():
            # clean up
            self.finished.disconnect(self._finished_handler)
            self.terminate()
            self.wait()