Limit onClick to chartArea

[kurkle]

Closes: #6044

Demo

[nagix]

It may be better to handle click events in beforeEvent in the legend plugin and to return false because this change could break existing applications?

[kurkle]

It may be better to handle click events in beforeEvent in the legend plugin and to return false because this change could break existing applications?

That would fire onClick on scales and could still break some applications.

[nagix]

Currently, click events are picked by legend's onClick and the chart-level onClick callbacks, but there is no callback in scales or other elements. onClick for the whole canvas has been available for long time, so I'm not sure it is breaking something.

On the other hand, click events on the legend cause a few problems as reported, I think this change (interception of click events by legend's onClick) is acceptable for most of users. How do you think?

[benmccann]

I think this probably makes sense. Users can add their own onClick to the canvas fairly easily if that's what they want.

Not a main consideration, but this PR would improve usability of the zoom plugin chartjs/chartjs-plugin-zoom#205

[simonbrunel]

I'm worry that there are existing implementations that listen for this click events and do hit test with scale elements or the title (e.g. open a "link"). I agree with @nagix, this is here since a very long time and I'm pretty sure it will break some projects.

[yusufozturk]

@kurkle @etimberg Thanks!