Python 在PyQt4中使用QRunnable的QThreadPool

考虑下面的代码片段

class Worker(QtCore.QRunnable):
    def __init__(self):
        super(Worker, self).__init__()

    def run(self):
        print('Running Worker')

class Tasks(QtCore.QObject):
    def __init__(self):
        super(Tasks, self).__init__()
        self.pool = QtCore.QThreadPool.globalInstance()
        self.pool.setMaxThreadCount(2)

    def start(self):
        for task in range(3):
            worker = Worker()
            self.pool.start(worker)
        self.pool.waitForDone()

def main():
    prefix_path = os.environ['QGIS_PREFIX_PATH']
    QgsApplication.setPrefixPath(prefix_path, True)
    QgsApplication.initQgis()
    tasks = Tasks()
    tasks.start()

我得到以下错误

_original_runnable_init(self, *args, **kwargs)
TypeError: keyword arguments are not supported

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工作对象创建有什么问题？

不知道QGis初始化有什么问题，但以下代码在我的机器中按预期工作：

from PyQt4 import QtCore

class Worker(QtCore.QRunnable):
    def __init__(self):
        super(Worker, self).__init__()

    def run(self):
        print('Running Worker')

class Tasks(QtCore.QObject):
    def __init__(self):
        super(Tasks, self).__init__()
        self.pool = QtCore.QThreadPool.globalInstance()
        self.pool.setMaxThreadCount(2)

    def start(self):
        for task in range(3):
            worker = Worker()
            self.pool.start(worker)
        self.pool.waitForDone()

if __name__ == '__main__':
    tasks = Tasks()
    tasks.start()

它提供了以下输出：

Running Worker
Running Worker
Running Worker

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不要复制编辑错误消息。发布整个追踪。