Lock Highlight (Unlock) mode
I've always wanted some kind of Lock Highlight feature:
Much like editing a Group after double-click (which grays out all other artboard objects while you edit only that grouped object), I'd like to be able to see a grayed out preview of all the locked objects.
With a keyboard shortcut (e.g. Ctrl + Shift + Alt + Click), you could Unlock individual elements, then exit Lock Highlight mode and keep working.
That would keep you from needing to go back around and relock other elements you didn't want to disturb.
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It’s an interesting idea actually.
The native way Illustrator offers today is the 'Select and Unlock objects on canvas' option in Preferences > Selection & Anchor Display. When it’s enabled, Ai shows small lock icons next to locked objects, if you try to click or marquee them.
Two downsides of the method I can immediately think of:
1. Objects behind locked ones won’t get selected anymore with a click (reported here: http://illustrator.uservoice.com/forums/601447/suggestions/48743753)
2. We still have to click or marquee to see the locks (that’s why a second request exists, to make this option into two: https://illustrator.uservoice.com/forums/333657/suggestions/48753221)The other method we can use is a context menu. Click a locked object and choose to unlock it; and if there are many objects behind the cursor, pick one form the list. A downside for this method — the list only has names, and no highlighting on canvas happens (requested here: http://illustrator.uservoice.com/forums/333657/suggestions/48881447)
Then, there are plugin tools that allow unlocking on canvas.
One would be Lock Unlock Tool by Astute Graphics: https://docs.astutegraphics.com/subscribe/lock-unlock-tool (and here’s a video: https://www.youtube.com/watch?v=s3BDGA5QKw0)
Another plugin tool is a free one, Unlocker Tool by n8ive studio: https://n8ivestudio.gumroad.com/l/HuZMu
Both plugin tools work very similarly — they highlight locked object when you pick the tool and allow to toggle the state.
The second one support marqueeing and separates Lock and Unlock operations with Opt/Alt.Please comment back if these methods suit you.