The Dash Callback - Input, Output, State, and more

The Callback is the most important element in Dash. You need to know it so you can create interactive dashboard apps. In this tutorial I'll show you how to use the callback to connect between the various components of your app, such as the dropdown, the graph, and the pie chart.

View my book - The Book of Dash:

Code:

Data:

Dash Documentation:

Supporting Document:

Video layout:
00:00 - What you will learn
02:37 - Start coding
04:29 - Single Input and Output
11:35 - State, PreventUpdate
22:49 - Callback facts you need to remember!

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[CharmingData]

Hey Everybody, I hope this tutorial helps you build those beautiful dashboards. Don't forget to download the code, the data, and the supporting docs, located under the video.

[ramon]

Your videos are the best, I was trying to find a way to trigger a callback only the button was pressed, and this State (which I didn't know so far) worked perfectly!

[trojansrck]

These are great! Better than Dash's official examples

[Qzbub]

This is great stuff brother. Thank You.

[Premsept]

Great explanation indeed!!
Thank you!

[SR-lfic]

hi, I am a bit confused about line 45 to 47 in your example. You said whatever returned in the function below the @call_back has to have the same properties as the output. The fig variable in the function update_my_graph is a px piechart, how is that a dictionary. I think I misunderstood your tutorial. Any further support in the reply will be truly appreciated.

[yasharrahimi]

Great tutorial.
Thank you so much. 😊👍

[rosmerybetancourt]

Excellent!! This is all i needed, thanks!

[aliabbas-syed]

Just subscribed to you. Your explanations are the best among all other videos. Just wanted to say one thing that dash_core_components package and dash_html_components are deprecated and so that imports to be replaced by from dash import html, dcc, Input, Output. right?

[wp]

Thank you, sir. A bit verbose, but very very useful

[absCT]

thanks for the video found the series really helpful however i was wondering if there was a video on multiple inputs/outputs along with a plotly graph, im struggling to get mine to work

thank you in advance!

[mrdatapsycho]

Hi, These are fantastic tutorial. But that would be fantastic if you provide a playlist which will be easier to follow. Currently the playlist looks random.

[samirahuseynli]

Could you pls advise why would a callback be triggered only once? btw I'm using the same element as output and input and calling callback in API call. Thanks in advance!

[sawon_stories]

I am trying to create a dashboard where the datatable will be displayed based on the value of dropdown. Using callback I am trying to do that but somehow it's not displaying anything because the dataframe is not defined properly in the code. Can you help me to debug that?

[abhinavshah]

I'm finding it difficult to use the callback function to display my scraping code (BS4) in a Tabular format.