Panel doesn't listen to title changed

[hbcarlos]

Description

Not sure if this is a bug, I would say it is.
MenuBar and TabBar listen to title changes on every inserted widget, but Panel doesn't.
MenuBar:

lumino/packages/widgets/src/menubar.ts

Line 229 in 705ffa9

menu.title.changed.connect(this._onTitleChanged, this);

TabBar:

lumino/packages/widgets/src/tabbar.ts

Line 430 in 705ffa9

title.changed.connect(this._onTitleChanged, this);

The problem is that the AccordionPanel extends Panel and uses its children titles to separate the widgets and show/hide the respective child. See screenshot:

I'm trying to update the title, but it doesn't update the widget since the accordion panel is not listening for changes.

Is this a bug in the Panel widget? Should I open a PR to listen for title changes in the Panel widget, or should I overwrite the addWidget and insertWidget in the AccordionPanel to listen for changes?

Reproduce

Expected behavior

Context

[blink1073]

I think that logic should go in AccordionPanel and not Panel if possible, since not every panel needs to concern itself with the titles of its children.

[hbcarlos]

Okay. Thanks, @blink1073. I'll open a PR!

[fcollonval]

Thanks for catching that one @hbcarlos
I agree with @blink1073 that this should be corrected only in the accordion panel.

[fcollonval]

Closing as the fix #249 has been merged.