View

All the files related to the GUI should be placed within the View package. This is the third leg of the MVC design pattern. If the Model is properly built, the Views are relatively simple PyQt objects. It is important to point out that if there is any logic of the experiment that goes into the view, the code is going to become harder to share, unless it is for the exact same purpose.

Start GUI

Convenience function to wrap the initialization of a window. The Experiment class should be created outside and passed as argument.

>>> experiment = Experiment()
>>> experiment.load_config('filename')
>>> experiment.load_daq()
>>> start_gui(experiment)

PFTL.view.start_gui.start_gui(experiment)[source]: Starts a GUI for the ScanWindow using the provided experiment. :param Experiment experiment: Experiment object with a loaded config.

Main Window

This is the central code for the user interface of Python for the Lab. The design of the window is specifcied in its own .ui file, generated with Qt Designer.

class PFTL.view.main_window.MainWindow(experiment=None)[source]

Bases: QMainWindow

Main Window for the user interface

Parameters:: experiment (Experiment) – Experiment model, can be left empty just for testing. Should be instantiated and initialized before passing it.

experiment

The experiment object

Type:: Experiment

plot_widget

Widget to hold the plot

Type:: pg.PlotWidget

plot

The real plot that can be updated with new data

Type:: pg.PlotWidget.plotItem

start_button

The start button

Type:: QPushButton

start_scan()[source]: Wrapper that updates the values from the UI (start, stop, num_steps, delay, channel_in, channel_out) before starting the scan.

Warning

There is a bug in this code (left for students to find out and sort it). If a user changes the values on the UI and presses “start” again, the metadata will store the new values, not the proper ones.

stop_scan()[source]: Stops the scan. It is wrapping the stop_scan() method. The only reason to do it this way is in case stopping a scan requires more work, for example stopping timers to prevent useless updates, etc.

update_gui()[source]: It is called on a timer to display the latest values of the applied voltage and the measured voltage.

update_plot()[source]: This method is called periodically via a QTimer. It updates the plot to show what is currently available in the experiment data. If the acquisition is over, the timer is stopped (this prevents wasting computation resources updating a plot that does not change).