This repository contains a prototype viewer for glue which uses state objects to carry around the state for various ui elements. All communication between classes is effectively done by modifying the state and having callbacks. The main classes/objects are the following:

ScatterViewer: the main DataViewer class - rather than have attributes, this class has a viewer_state attribute that contains an instance of the ScatterViewerState class, which contains all the information required to describe the viewer itself. This includes xatt, yatt, and layers (a set of all the datasets and subsets currently in the viewer).

The options for the ScatterViewer are controlled from the ScatterOptionsWidget widget, which is given access to the ScatterViewerState. The appearance of this widget is defined in the optins_widget.ui file, and we auto-link the widgets in that layout to the attributes in the ScatterViewerState (we do this based on the name of the widgets and state attributes).

The ScatterViewer instantiates ScatterLayerArtist objects which are given the ScatterViewerState as well as the Matplotlib Axes. In this way, the layer artists can register to receive callbacks from the ScatterViewerState whenever e.g. one of the x or y attributes is changed. In addition, the ScatterLayerArtist defines its own state object for things related to the visual settings or that particular layer artist. However, some of the settings are actually already defined in the style attribute of Data objects, so essentially the ScatterLayerArtist has two state objects, one global one for the data, and one with additional options specific to this viewer.

In the example here, the marker size and color are global Data attributes, while we have a third option to join or not the points, which is an option local to this viewer.

To run the example, simply do:

python example.py

Note that the helpers.py file is not specific to this viewer and will be code shared by the different viewers.