René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Can not read properties of undefined 'X'","articleBody":"Using virtualization=True and style_data_conditional throws an error of 'can not read properties of undefined column_name'.  Here is an MWE to test with, scroll down a bit on the table and then select a cell in the last column.  I created a topic on the community forum and the results were it seems to be a bug.  [Community Topic](https://community.plotly.com/t/cannot-read-properties-of-undefined/67103/2)\r\n\r\n````\r\nimport dash\r\nimport dash_table\r\nimport dash_html_components as html\r\nfrom dash.dependencies import Input, Output, State, MATCH, ALL\r\nimport pandas as pd\r\n\r\napp = dash.Dash(__name__)\r\n\r\ndf = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/Emissions%20Data.csv').reset_index()\r\ndf['Emission'] = df['Emission'].map(lambda x: '{0:.2f}'.format(x))\r\n\r\napp.layout = html.Div([html.Div([], id='test'), dash_table.DataTable(\r\n    id='table',\r\n        data=df.to_dict('records'),\r\n        columns=[{'id': c, 'name': c} for c in df.columns],\r\n        editable=True,\r\n        filter_action=\"native\",\r\n        sort_action=\"native\",\r\n        sort_mode=\"multi\",\r\n        page_action=\"none\",\r\n\t\tfixed_rows={'headers': True, 'data': 0},\r\n\t\t#sort_action='native',\r\n\t\texport_format=\"xlsx\",\r\n\t\texport_headers=\"display\",\r\n\t\texport_columns='all',\r\n\t\t#filter_action='native',\t\t\r\n        virtualization=True,\r\n\t\tstyle_data_conditional=[{\r\n\t\t\t\t\t'if': {\r\n\t\t\t\t\t\t'filter_query': '{Emission} \u003e 0',\r\n\t\t\t\t\t\t'column_id': 'Emission'\r\n\t\t\t\t\t},\r\n\t\t\t\t\t'color': 'green'\r\n\t\t\t\t},\r\n\t\t\t\t{\r\n\t\t\t\t\t'if': {\r\n\t\t\t\t\t\t'filter_query': '{Emission} \u003c 0',\r\n\t\t\t\t\t\t'column_id': 'Emission'\r\n\t\t\t\t\t},\r\n\t\t\t\t\t'color': 'red'\r\n\t\t\t\t}],\r\n\t\ttooltip_conditional=[\r\n\t\t\t{\r\n\t\t\t\t'if': {\r\n\t\t\t\t\t'filter_query': '{Emission} \u003c 0',\r\n\t\t\t\t\t\t'column_id': 'Emission'\r\n\t\t\t\t\t\t},\r\n\t\t\t\t'value': 'Further review required, calculated demand is 20% lower than the 3 year average units sold'\r\n\t\t\t},\r\n\t\t\t{\r\n\t\t\t\t'if': {\r\n\t\t\t\t\t'filter_query': '{Emission} \u003e 0',\r\n\t\t\t\t\t\t'column_id': 'Emission'\r\n\t\t\t\t\t\t},\r\n\t\t\t\t'value': 'Further review required, calculated demand is 20% higher than the 3 year average units sold'\r\n\t\t\t},\r\n\t\t]\r\n)\r\n])\r\n\r\n\r\n@app.callback(Output('test', 'children'), [Input('table', 'active_cell')])\r\ndef updateIT(ac):\r\n\tif ac:\r\n\t\treturn ac['column_id']\r\n\telse:\r\n\t\treturn ''\r\n\t\r\n\t\r\nif __name__ == '__main__':\r\n\tapp.run_server(debug=True)\r\n````\r\n\r\n","author":{"url":"https://github.com/croll12-creator","@type":"Person","name":"croll12-creator"},"datePublished":"2022-08-28T11:35:08.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/950/dash-table/issues/950"}