Control, Control, You Must Learn Control - Unity 3D UI Essentials - page 126

The Toggle specific options that are exposed (in the middle) give us a few capabilities:

• Is On : This determines the initial state of the Toggle , active/checked
• Toggle Transition : This controls how the toggle graphic enters and exits the
view, blinkered on/off or fades in/out (default)

There are only two options at present for the transition, I would have
liked to see more or at least a Mecanim hook-in here. Hopefully, it'll be
extended in future updates. If not, then you can always do it yourself.

• Graphic : This is the sprite to use for the check image ( not the checkmark
GameObject as shown previously, which is the checkmark background),
this is the image that is turned on/off by the Toggle
• Group : We'll cover this later, essentially, it allows for grouping of Toggle
options together, only allowing a single item in a group to be checked at a time

So from the default setup that Unity gives you, all that is needed is a Toggle
graphic and you're done, but as Unity shows, you should really think beyond
that for a good UX.

Grouping toggles
As described earlier, in the Toggle control's properties, multiple toggles can be
grouped together under a single group. The net effect of a toggle group means that
only one Toggle within the group can be active (checked true) at a time. This is great
for those multiple choice situations where there can only be one right answer.

Groups can be placed anywhere on the scene, the best option however, is to create a
parent empty GameObject, add the Toggle Group component to it, and then place
each toggle that is part of the group as a child of this parent GameObject. For example:

1. In a new scene, create a Canvas and add an empty Empty GameObject as its

child. Name this new GameObject Toggle Group Parent .

2. Add the Toggle Group component to the Toggle Group Parent GameObject.

3. Add a Toggle control as a child of the Toggle Group Parent GameObject.

4. Select the Toggle and drag the Toggle Group Parent to the Group property

of the Toggle component.

5. Set the Is On property to False (unchecked).