I have a python program that displays no errors when I run it but doesn't give any kind of output. It only displays:
"Dash is running on http://127.0.0.1:8050/
- Serving Flask app 'Editable_Table'
- Debug mode: on"
No other output is given. It gives the same result when I run it directly from the command line.
I tried doing some research and read that a potential problem is defining the main() function. I don't know how to do that (ultra beginner to coding here) and everything I tried doesn't work. I have "
if __name__ == "__main__":
app.run_server(debug=True)
at the end of the program, and I tried defining main() as
def main():
main()
and switching the main() and app.run_server(debug=True) lines.
Here's the full code:
from dash import Dash, dash_table, dcc, html
from dash.dependencies import Input, Output, State
app = Dash(__name__)
app.layout = html.Div([
html.Div([
dcc.Input(
id='adding-rows-name',
placeholder='Enter a column name...',
value='',
style={'padding': 10}
),
html.Button('Add Column', id='adding-rows-button', n_clicks=0)
], style={'height': 50}),
dash_table.DataTable(
id='adding-rows-table',
columns=[{
'name': 'Column {}'.format(i),
'id': 'column-{}'.format(i),
'deletable': True,
'renamable': True
} for i in range(1, 5)],
data=[
{'column-{}'.format(i): (j + (i-1)*5) for i in range(1, 5)}
for j in range(5)
],
editable=True,
row_deletable=True
),
html.Button('Add Row', id='editing-rows-button', n_clicks=0),
dcc.Graph(id='adding-rows-graph')
])
@app.callback(
Output('adding-rows-table', 'data'),
Input('editing-rows-button', 'n_clicks'),
State('adding-rows-table', 'data'),
State('adding-rows-table', 'columns'))
def add_row(n_clicks, rows, columns):
if n_clicks > 0:
rows.append({c['id']: '' for c in columns})
return rows
@app.callback(
Output('adding-rows-table', 'columns'),
Input('adding-rows-button', 'n_clicks'),
State('adding-rows-name', 'value'),
State('adding-rows-table', 'columns'))
def update_columns(n_clicks, value, existing_columns):
if n_clicks > 0:
existing_columns.append({
'id': value, 'name': value,
'renamable': True, 'deletable': True
})
return existing_columns
@app.callback(
Output('adding-rows-graph', 'figure'),
Input('adding-rows-table', 'data'),
Input('adding-rows-table', 'columns'))
def display_output(rows, columns):
return {
'data': [{
'type': 'heatmap',
'z': [[row.get(c['id'], None) for c in columns] for row in rows],
'x': [c['name'] for c in columns]
}]
}
def main():
main()
if __name__ == "__main__":
app.run_server(debug=True)
