Colliders and Alpha

[Yukichu]

Attempting to create "invisible" collider for UI.

Attempt 1:  UIWidget + Collider = fail
Attempt 2:  UISprite (Alpha 0) + Collider = fail
Attempt 3:  UISprite (Alpha 1/255) + Collider = success

I have it working and that's great, just wondering why UICamera.lastHit.collider doesn't register unless there is some alpha there, or am I mistaken?  Didn't change any other settings.

Mmmm... addendum, the panel is set to "Visible" so I am guessing it's checking for a visible component.  Not 100% sure, but this makes sense.  Will have to test more later.

[RobBrooks]

Yeah I had this too in a UIButton where I needed to make the UISprite disappear on rollover.
So I just gave the rollover colour an alpha of zero to clear it because that was the most direct way of doing it.
Unfortunately, this meant I was then unable to click the button once I'd rolled over it because there was effectively no graphical representation there and that appeared to defeat the process.
So I just set the alpha to 1/255 which was near transparent enough to be imperceptible.

[ArenMook]

UIWidget + Collider is the way to do it. ALT+SHIFT+W, ALT+SHIFT+C.

Not sure why you marked it as "fail". All sprites derive from UIWidget, and the alpha checking code comes straight from UIWidget.