Chart Events and Methods¶

Events¶

The HighCharts component supports events that allow making charts more interactive:

point_click - fires when a point is clicked
point_select - fires when a point is selected
point_unselect - fires when point is unselected
series_hide - fires when series is hidden
series_show - fires when series is shown
series_click - fires when series is clicked
tooltip - fires when chart requests a tooltip (covered in its own chapter in the tutorial)

For all chart events, JustPy adds the following fields to the second argument of the event handler (msg in this tutorial): - msg.x - the x value of the point - msg.y - the y value of the point - msg.category - the category value of the point - msg.color - the point's color - msg.series_name - the name of the series the point is in - msg.series_index - the index of the series the point is in - msg.point_index - the index of the point in the series

Methods¶

`async def draw_crosshair(self, point_list, websocket)`¶

Draw crosshairs for designated points.

    async def draw_crosshair(self, point_list, websocket):
        # data is list of of dictionaries  whose keys are:
        # 'id': the chart id 
        # 'series': the series index
        # 'point': the point index 
        #  Values are  all integers
        # Example:
        # {'id': chart_id, 'series': msg.series_index, 'point': msg.point_index}
        await websocket.send_json({'type': 'draw_crosshair', 'data': point_list})
        # So the page itself does not update, only the tooltip, return True not None
        return True

See example of usage in Iris Flower Dataset Visualization

`async def select_point(self, point_list, websocket)`¶

Selects designated points.

async def select_point(self, point_list, websocket):
    # data is list of of dictionaries  whose keys are:
    # 'id': the chart id 
    # 'series': the series index
    # 'point': the point index 
    #  Values are  all integers
    # Example:
    # {'id': chart_id, 'series': msg.series_index, 'point': msg.point_index}
    await websocket.send_json({'type': 'select_point', 'data': point_list})
    # So the page itself does not update, only the tooltip, return True not None
    return True