Configuration and Control Interfaces¶
Device configuration and control is done through ‘interfaces,’ objects that encapsulate the
processes. Typically, neither of these interfaces are explicitly created; accessing
Recorder.config and Recorder.command will automatically instantiate a
ConfigInterface or CommandInterface subclass
appropriate for the given device.
There is some overlap between the configuration and command interfaces; for example, configuring Wi-Fi or setting a device’s clock are handled through the command interface. As a rule, changes that happen immediately are commands, and changes that apply after the recorder restarts (e.g., being reset, starting a recording, being disconnected) are handled by the configuration interface.
Configuration¶
Control¶
Special Notes¶
Callback Functions¶
Several commands feature a parameter for a callback function, which will be called periodically during potentially long-running functions. Callbacks are primarily intended for use with GUIs. If the function returns True, the command will be cancelled. Also, in cases in which the command is executing in the foreground thread, the callback creates an opportunity to update the UI.
Callback functions require no arguments, but for the sake of future-proofing, it is recommended that the functions accept them. In the future, commands may provide information via arguments (e.g., the percentage completed, elapsed time, etc.).
def my_callback(*args, **kwargs):
""" Fake example callback function. Accepts any positional or keyword arguments,
but ignores them. Setting the global variable `keep_going` to `True` will
make the function return `True`, cancelling the command to which the callback
function was provided.
"""
# Something could happen here, like yielding some cycles to the GUI.
# ...
if keep_going:
return False
else:
return True