Ubuntu – Half selected effect in Kubuntu

kdekubuntu

Can someone tell me the differences between the two types of selections in the pictures below (half square and full square)?

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Best Answer

According to KDE Visual Design Group/HIG/CheckBox:

A check box is a control that permits the user to make multiple selections from a number of options. Check boxes are used to toggle an option on or off, or to select or deselect an item. Users make a decision between two clearly opposite choices, e.g. 'on vs. off', 'apply vs. don't apply', 'show vs. hide'.

And further down there's an illustration of the partially filled checkbox with this:

Use the mixed state only to indicate that an option is set for some, but not all, child objects. ...

Checkbox_Mixed_State.qml.png

And this is what I see with a clean, default user account on Kubuntu 18.04:

Tri-state checkboxes

In the comment section below this answer, user26687 has provided a link to a comment by a developer, d_ed, in There are several settings in KDE that have a "half-checked" state. What do they mean?:

That the current value is evaluated by something else but can be overridden here.

So what you're seeing is by design even if it's not very obvious regarding the function!