qtlets

Automatic linking of data to qt widgets. MCV without the boilerplate.

qtlets provides a simple way to keep in sync Qt widgets and data, without forcing a redesign of your data classes. The rule is: if you like your class, you can keep your class.

Currently, bidirectional linking can be performed in a simple call¹: instance.link_widget(my_widget, "name") The data displayed on my_widget will be updated whenever instance.name is modified. Changing the value on my_widget will update instance.name. Multiple widgets can be kept synchronized in this way.

This functionnality is provided by a lightweight Mixin class called HasQtlets. To enable qtlets on an Existing class, simply do:

class Data(HasQtlets, Existing): pass

and then use Data as a drop-in replacement for Existing. To link widgets, make calls to link_widget. The widget should be able to send and receive the appropriate data type. A few basic types are availalbe in qtlets.widgets

This library is currently in early stages. The documentation is light, and the API is changing quickly. All help is appreciated...

¹ Some conditions currently apply, see the Features section.

Getting started

Requires Python 3.8+.

Installation

Regular installation

pip install qtlets

Development installation

For development, clone the repository and install with dev dependencies:

pip install -e ".[dev]"

Running tests

After installation:

pytest

Features

The following features are currently supported:

• Linking of widgets and data. Currently, scalar data members are supported;
• Multiple widgets can be linked with the same data attribute;
• Compatibility with simple vanilla classes, as well as more complex third-party libraries such as traitlets (Even attrs! Isn't inheritance wonderful?);
• Support for properties;
• The signal and slots used to communicate with the widget can be specified explicitly. For some widgets, a reasonable default is provided.

The following features are desired:

• Adding more data types and widgets.
• Streamlined type conversions and checks. For type conversion, we can pass conversion functions to link_widget.
• Support for collections attributes (ex: instance.values = [])
• Support polling (inst.link(widget, attrname, poll_interval=15))
• Leverage Qt's thread affinity when using signals and slots, for setting as well as for getting.
• More dedicated widgets.
• Use either PySide6 or PyQt. See how pyqtgraph does it.