SafeLoopThread

class privex.helpers.thread.SafeLoopThread(*args, default_stop=False, default_pause=False, **kwargs)

__init__(*args, default_stop=False, default_pause=False, **kwargs)

This is a simple loop thread class which uses StopperThread to allow an application to signal to the thread that it should shutdown or temporarily pause the loop.

Note that if you have a long loop which takes a long time to run, you should regularly check should_stop and should_pause within your loop, so that the loop can shutdown or pause quickly when you request it to.

Example usage:

>>> # Create a sub-class of SafeLoopThread, and implement a loop() method
>>> class MyThread(SafeLoopThread):
...     loop_sleep = 2    # 'run' will wait this many seconds between each run of your loop(). set to 0 to disable loop sleeps
...     def loop(self):
...         print("I'm looping!")
...
>>> t = MyThread(default_pause=True)
>>> t.start()
>>> # No output because default_pause was set to True. To start the loop, we'll unpause it
>>> t.emit_unpause()
I'm looping!
I'm looping!
I'm looping!
>>> t.emit_pause()
>>> # We can re-pause the loop from our main thread, and the output stops again.
>>> # If we unpause the thread again, we can also ask the thread to stop looping and shutdown using emit_stop
>>> t.emit_unpause()
I'm looping!
I'm looping!
>>> t.emit_stop()
>>> t.is_alive()
False
>>> # Because we sent a STOP event, 'run' stopped looping, and returned.
>>> # To be able to start the same thread object again, we'd need to clear the STOP event first
>>> t.emit_start()  # Clear the STOP event we set with emit_stop
>>> t.start()       # Start the thread again
I'm looping!
I'm looping!

Parameters

• args –

• default_stop – If True, will trigger the event ev_stop in the constructor, which will prevent the thread from being able to start until ev_stop is cleared e.g. via emit_start()

• default_pause – If True, will trigger the event ev_pause in the constructor, which will cause ‘run’ to wait until ev_pause is cleared e.g. via emit_unpause() before starting the loop

• kwargs –

Key List[Union[Event,BetterEvent]] stop_events

Additional Event or BetterEvent ‘s which when set, will cause should_stop to become True.

Key List[Union[Event,BetterEvent]] pause_events

Additional Event or BetterEvent ‘s which when set, will cause should_pause to become True.

Methods

Methods

__init__(*args[, default_stop, default_pause])	This is a simple loop thread class which uses StopperThread to allow an application to signal to the thread that it should shutdown or temporarily pause the loop.
loop()
run()	Method representing the thread’s activity.

Attributes

Attributes

loop_sleep
pause_sleep