LayerControl: Add 'Toggle all layers' menu item to layer control options

[jebu75]

It would be useful to have an option to toggle all sublayers either on or off when clicking on a layer name in the Layer Control widget.

This isn't a great mockup but will hopefully illustrate the idea:

[DavidSpriggs]

Toggle off or on? A true toggle would flip whatever is set.

[jebu75]

The idea would be to quickly turn on/off all sublayers. The original idea (see #230), was to be able turn a all layers on or off. Sort of like pretty standard 'select all/select none' functionality for a group of checkboxes. @btfou had the idea that this might be useful for all sub-layers of an operational layer as well.

[friendde]

Can we replicate ArcMap and use CTRL + click to turn off/on all layers at once?

[friendde]

No bad idea sorry that would not work across all devices.

[jebu75]

It might not work for all all devices but would work on a desktop with the menu item for mobile. The problem I see is how does a user know they can do that? There would not be any indication in the UI and you put a hint, you would have to remove it on mobile. Seems like it might get over complicated.

[tmcgee]

Dave has a point about the connotation of toggling The action should be made more clear. I suggest perhaps two menu choices. Something like

`Show All Layers in Folder`
`Hide All Layers in Folder`

or

`Turn On All Layers in Folder`
`Turn Off All Layers in Folder`

I prefer the first set.

[jebu75]

I agree with two choices. The titles might need to be shorter, just have to see how it lays out I guess.

[tmcgee]

As far as hints in the UI, the different color of the layer name is a good hint. I think adding a small menu icon floating to the right of the layer name is an additional and arguably better "clue". I believe that adding the icon could be handled with CSS for a particular app so no code changes required.

EDIT: Ignore this comment here. I do not want to subvert the original issue. ;)

[DavidSpriggs]

I like the idea of an icon to open the menu rather than a blue text link. A small gear icon from FA would work nicely.

[tmcgee]

I will create a separate issue for the icon. Sorry for the tangent...

[btfou]

If I can get some consensus on an icon replacing the link, and some thoughts on these items, I'll do it.

1. Gear or something else
2. Where? after of before the checkbox? or at the far right?
3. I was also considering a solid background for the top level of the control for better differentiation.

[jebu75]

I vote for the gear at the far right, that or a drop down icon. The css classes should be documented to aide developers in customizing to their own needs.

[jebu75]

I like @tmcgee's idea of creating a separate issue to discuss how the layer menu is opened. This issue was more about menu items related turning all sublayers on and off.

[tmcgee]

Discussion of icon should stop here and continue in issue #231

[btfou]

@jebu75 @tmcgee Dynamic layer menu (w/ sublayers) has turn all on/off menu items. https://github.com/cmv/cmv-app/tree/LayerControl-1.3.1-patch