On my content type, I have a boolean field which consists of a single on/off checkbox.
I have created a view, which shows all the nodes of that content type. However, I only want the view to show nodes where the boolean field has been ticked. How can I do this?
I thought in Views I could use "Filter criteria > Content: [Name of Field]."
However, when I select this, the only option available is "Select All". If I select this, I get the following error message:
No valid values found on filter: Content: Show on Main Navigation.
What am I doing wrong?