ltk

LTK is a little toolkit for writing UIs in PyScript

LTK is implemented as a declarative Python library and leverages jQuery for DOM operations.

Widget Specification

New widget types are created by symply subclassing ltk.Widget:

class HBox(Widget):
    classes = [ "ltk-hbox" ]

By default, widgets are created as div DOM elements. You can choose a different tag:

class Preformatted(Widget):
    classes = [ "ltk-pre" ]
    tag = "pre"

Creating a UI

To create a UI, elements are constructed declaratively:

ltk.Table(
    ltk.TableRow(
        ltk.TableHeader("header1")
        ltk.TableHeader("header2")
    ),
    [
        ltk.TableRow(
            ltk.TableData(value1),
            ltk.TableData(value2),
        )
        for value1, value2 in data
    ],
)

Widgets are added to others by using jQuery's append and appendTo calls:

ltk.body.append(
    ltk.Table(...)
)

container = ltk.VBox(...)
ltk.H1("This is a header").appendTo(container)

Styling

Widgets can be styled using element styles:

ltk.Text("Some text")
    .css("background-color", "red")
    .css("color", "white")
    .css("padding", 8)

Widgets can also be styled using an external stylesheet:

ltk.Text("Some text").addClass("my-special-text)

.ltk-text {
    font-family: Arial;
}

.my-special-text {
    font-family: Courier;
    background-color: red;
    color: white;
    padding: 8px;
}

Events

Event handlers are attached using jQuery mechanisms. As the functions cross PyOdide and JavaScript namespaces, they need to be wrapped with pyodide.ffi.create_proxy calls. We use the shortcut offered by ltk.proxy:

def buy(event):
    purchase(...)

Card("Buy Now").on("click", ltk.proxy(buy))

Examples

See the LTK Kitchen Sink or explore the examples folder

License

LTK is covered under the Apache License:

• The Apache license is a permissive open source software license.

• It allows users to freely use, modify, and distribute the software (including for commercial purposes).

• Modified versions can be distributed without having to release the source code. Though source code changes should be documented.

• The license requires modified versions to retain the Apache license and copyright notice.

• The software is provided by the authors "as is" with no warranties.

• Users are not granted patent rights by contributors, but contributors cannot revoke patent grants for previous contributions.

• The license does not require derived works to adopt the Apache license. Though this is encouraged for consistency.