Pattern call-backs regarding adding dynamic graphs

Hello,

Where can i see an example of the callback pattern shown in plotly’s article where you can add a graph dynamically that is within a div with associated dropdowns. Can someone please give me guidance on how to go about doing this?

How did the create of the article dynamically create a div that has an “x” in the top right corner so that the graph can be cleared on click. If the code for this article is available, it would be great.

Hi! Did you get it? I was wondering exactly the same.

Hello, no I was not able to figure it out. lol

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Hi!

I got this to work by adding a button with an “X” that would trigger the callback to remove the chart.

Here is this feature added to the example app from 📣 Dash v1.11.0 Release - Introducing Pattern-Matching Callbacks

import dash
from dash.dependencies import Input, Output, State, ALL, MATCH
import dash_html_components as html
import dash_core_components as dcc
import plotly.express as px
import json

df = px.data.gapminder()

app = dash.Dash(__name__)

app.layout = html.Div(
    [
        html.Div(
            children=[
                dcc.Dropdown(
                    options=[{"label": i, "value": i} for i in df.country.unique()],
                    value="Canada",
                    id="country",
                    style={"display": "inline-block", "width": 200},
                ),
                html.Button(
                    "Add Chart",
                    id="add-chart",
                    n_clicks=0,
                    style={"display": "inline-block"},
                ),
            ]
        ),
        html.Div(id="container", children=[]),
    ]
)


def create_figure(column_x, column_y, country):
    chart_type = px.line if column_x == "year" else px.scatter
    return (
        chart_type(df.query("country == '{}'".format(country)), x=column_x, y=column_y,)
        .update_layout(
            title="{} {} vs {}".format(country, column_x, column_y),
            margin_l=10,
            margin_r=0,
            margin_b=30,
        )
        .update_xaxes(title_text="")
        .update_yaxes(title_text="")
    )


@app.callback(
    Output("container", "children"),
    [
        Input("add-chart", "n_clicks"),
        Input({"type": "dynamic-delete", "index": ALL}, "n_clicks"),
    ],
    [State("container", "children"), State("country", "value")],
)
def display_dropdowns(n_clicks, _, children, country):
    default_column_x = "year"
    default_column_y = "gdpPercap"

    input_id = dash.callback_context.triggered[0]["prop_id"].split(".")[0]
    if "index" in input_id:
        delete_chart = json.loads(input_id)["index"]
        children = [
            chart
            for chart in children
            if "'index': " + str(delete_chart) not in str(chart)
        ]
    else:
        new_element = html.Div(
            style={
                "width": "23%",
                "display": "inline-block",
                "outline": "thin lightgrey solid",
                "padding": 10,
            },
            children=[
                html.Button(
                    "X",
                    id={"type": "dynamic-delete", "index": n_clicks},
                    n_clicks=0,
                    style={"display": "block"},
                ),
                dcc.Graph(
                    id={"type": "dynamic-output", "index": n_clicks},
                    style={"height": 300},
                    figure=create_figure(default_column_x, default_column_y, country),
                ),
                dcc.Dropdown(
                    id={"type": "dynamic-dropdown-x", "index": n_clicks},
                    options=[{"label": i, "value": i} for i in df.columns],
                    value=default_column_x,
                ),
                dcc.Dropdown(
                    id={"type": "dynamic-dropdown-y", "index": n_clicks},
                    options=[{"label": i, "value": i} for i in df.columns],
                    value=default_column_y,
                ),
            ],
        )
        children.append(new_element)
    return children


@app.callback(
    Output({"type": "dynamic-output", "index": MATCH}, "figure"),
    [
        Input({"type": "dynamic-dropdown-x", "index": MATCH}, "value"),
        Input({"type": "dynamic-dropdown-y", "index": MATCH}, "value"),
        Input("country", "value"),
    ],
)
def display_output(column_x, column_y, country):
    return create_figure(column_x, column_y, country)


if __name__ == "__main__":
    app.run_server(debug=True)

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