interaction_callbacks_for_tools.py — Anaconda Enterprise 4.4 documentation

Anaconda Enterprise: Documentation

# interaction_callbacks_for_tools.py

    from bokeh.models import CustomJS, ColumnDataSource, BoxSelectTool, Range1d, Rect
    from bokeh.plotting import figure, output_file, show

    output_file("boxselecttool_callback.html")

    source = ColumnDataSource(data=dict(x=[], y=[], width=[], height=[]))

    callback = CustomJS(args=dict(source=source), code="""
            // get data source from Callback args
            var data = source.data;

            /// get BoxSelectTool dimensions from cb_data parameter of Callback
            var geometry = cb_data['geometry'];

            /// calculate Rect attributes
            var width = geometry['x1'] - geometry['x0'];
            var height = geometry['y1'] - geometry['y0'];
            var x = geometry['x0'] + width/2;
            var y = geometry['y0'] + height/2;

            /// update data source with new Rect attributes
            data['x'].push(x);
            data['y'].push(y);
            data['width'].push(width);
            data['height'].push(height);

            // emit update of data source
            source.change.emit();
        """)

    box_select = BoxSelectTool(callback=callback)

    p = figure(plot_width=400,
               plot_height=400,
               tools=[box_select],
               title="Select Below",
               x_range=Range1d(start=0.0, end=1.0),
               y_range=Range1d(start=0.0, end=1.0))

    rect = Rect(x='x',
                y='y',
                width='width',
                height='height',
                fill_alpha=0.3,
                fill_color='#009933')

    p.add_glyph(source, rect, selection_glyph=rect, nonselection_glyph=rect)
    show(p)