add a "forget all plots" button in the plot pane

[viryfred]

Hi,

I added a button "forget all plots" in the plot pane:

I am far far away to be an expert of JS (first JS code), but here are the intended behavior: decrease the memory consumption (e.g. when performing live plotting).

Thank you in advance to take this feature into account.

[pfitzseb]

Thanks for the contribution!

I'd prefer a solution that doesn't try to update the DOM that often -- you should be able to teardown all items and then just empty this.items and this.ids and then this.activateItem(0) or something like that.

If you want to implement it in that way I'll hold off on merging, otherwise I can just merge and make the change myself -- up to you :)

Oh, and it would be cool if we could find another icon for this button.

[viryfred]

Thanks for your quick answer!

I prefer you merge and make the change, I never programmed in Javascript (that's why I tried the straightforward solution for me), even if I understand the idea behind your solution for performance.

Concerning the icon, where are stored the resources? In which format? I have two propositions:

• a circle slash plus a "All" at the bottom right corner (the most explicit icon, but the "All" can be difficult to read)
• a circle slash plus a backslash (in the same spirit than the "forget plot" icon, but stronger with the backslash)

[pfitzseb]

There are a couple of built-in icons that you can see in the "Styleguide" (just type that into the command paletter).

I've gone with this for now:

Thanks again for the PR, this was definitely a necessary feature! :)