[3.4.1] not able to detect which bar was clicked (working in 2.x)

[jacekkarczmarczyk]

Expected Behavior

In 2.x when clicking on the bar of the bar chart I was able to tell which bar was clicked, it doesn't work any more in 3.x and I don't see it mentioned in the migration guide

Current Behavior

Second argument of the options.onClick contains always all bars (series? sorry, not sure about the nomenclature, see the reproduction)

Possible Solution

Pass only the clicked bar instead of all, or add additional argument to the onClick

Steps to Reproduce

https://codepen.io/jkarczm/pen/VwbjyRa?editors=1010

Click the left bar and the right bar - how to distinguish which one was clicked?

Context

I have daily chart with bar per user, so clicking on the bar shows the data for clicked date and user

Environment

• Chart.js version: 3.4.1
• Browser name and version: Chrome
• Link to your project:

[etimberg]

One option is to set the interaction mode to 'nearest' https://codepen.io/etimberg/pen/mdmEXbm?editors=1010

Another option is to have the onClick handler look directly under the mouse point using getElementsAtEventForMode https://codepen.io/etimberg/pen/xxdOpox?editors=1010

[jacekkarczmarczyk]

Excelent, thank you! Am I right about this change not being mentioned in the migration guide though?

[jacekkarczmarczyk]

BTW, both examples link to the same codepen

[etimberg]

Sorry about that; I fixed the links.

I looked back at the 2.9 source code and it appears that it called onClick the same way with all of the active elements. I'm kind of surprised that there is a change though, because the default interaction modes should be identical. I'm happy to look at a PR updating the migration docs though 😄

[etimberg]

I think I found the discrepancy. In 2.9, the hover mode defaulted to index whereas the tooltip mode defaulted to nearest. We normalized both those defaults in 3.0, which is why this changed