My Dash plotly app not working

Dash Python
1

Hi, I have scripted an web app with dash.plotly. But having issues with it. Can anyone help me with it? I need it to be submitted tonight as a project.

2

Hello @moizbaloch1,

Welcome to the community!

This request is very vague, could you please provide more info about where you are having the issue.

Also, can you provide a MRE:

3 
import dash
from dash import html, dcc

PopulationDistribution = dash.Dash(__name__, use_pages=True)

PopulationDistribution.layout = html.Div(
    [
        # main app framework
        html.Div("WorldWide Population Distribution", style={'fontSize':50, 'textAlign':'center'}),
        html.Div([
            dcc.Link(page['name']+"  |  ", href=page['path'])
            for page in dash.page_registry.values()
        ]),
        html.Hr(),

        # content of each page
        dash.page_container
    ]
)


if __name__ == "__main__":
    PopulationDistribution.run(debug=True)`Preformatted text`
4

Thank you, @moizbaloch1.

Do you have a pages folder in that directory? If not, your app wont load because it cant parse through any files.

Also, here is a standard way to initialize:

import dash
from dash import html, dcc, Dash

app = Dash(__name__, use_pages=True)

app.layout = html.Div(
    [
        # main app framework
        html.Div("WorldWide Population Distribution", style={'fontSize':50, 'textAlign':'center'}),
        html.Div([
            dcc.Link(page['name']+"  |  ", href=page['path'])
            for page in dash.page_registry.values()
        ]),
        html.Hr(),

        # content of each page
        dash.page_container
    ]
)


if __name__ == "__main__":
    app.run(debug=True, port=12345)

The main thing was that typically we call it app, that way its easier to reference and copy & paste code. :slight_smile:

5

I have directory for pages and also data file

6

Hmm…

The application runs fine if I have a pages_folder.

Are you having issues with a specific folder? Can you copy my code and use it? Does it work?

1 Like
7

Appis loading but , when i move to another page. there is an error that page not found Error 404

8

Can you post your other pages.py?

Do you have layout = in each?

9 
import dash
from dash import dcc, html
import plotly.express as px
import pandas as pd 

dash.register_page(__name__)

df = pd.read_csv(r'd:\New\Data.csv')

layout = html.Div(
    [
        dcc.Dropdown([x for x in df.year.unique()], id='cont-choice', style={'width':'50%'}),
        dcc.Graph(id='line-fig',
                  figure=px.bar(df, x='country', y='population'))
    ]
)
10

Another Page> Blockquote

import dash
from dash import dcc, html
import plotly.express as px
import pandas as pd

dash.register_page(name)

df = pd.read_csv(r’d:\New\Data.csv’)

layout = html.Div(
[
dcc.Dropdown([x for x in df.year.unique()], id=‘cont-choice’, style={‘width’:‘50%’}),
dcc.Graph(id=‘line-fig’,
figure=px.bar(df, x=‘country’, y=‘population’))
]
)

11

Are there any errors in the console or anything that could shed some light?

12

if its okay, Can I email it to you , the zip file.

13

Issue is naming of the files leads to an incompatible path.

However, you can declare the path when you register the page and then it will work. :slight_smile:

from dash import dcc, html
import plotly.express as px
import pandas as pd

dash.register_page(__name__, path='/pop_per_country_selected')

df = pd.read_csv(r'Data.csv')

layout = html.Div(
    [
        dcc.Dropdown([x for x in df.year.unique()], id='cont-choice', style={'width':'50%'}),
        dcc.Graph(id='line-fig',
                  figure=px.bar(df, x='country', y='population'))
    ]
)

image
image1858×509 37.5 KB

1 Like
14

Thank you, still not working for me though

15

You’ll need to do it on all your files.

Is your main page loading with the graphs?

1 Like