Angular Formly - Is it possible to change the fields className with expressionProperties

Question

I have an Angular Formly form with a checkbox and I want to set a class on the wrapper based on if the field is checked or not.

So in the same way that I can do

expressionProperties: {
    'templateOptions.label': '$viewValue'
}

is it possible to do something like

expressionProperties: {
    'className': '$viewValue'
}

I don't seem to be able to get it to work.

Answer 1

Here's how you'd do it: https://jsbin.com/nerijo/edit?js,output

Basic idea: Your wrapper can reference the formControl object to get the $viewValue directly. You could also have it reference a data property that you set with expressionProperties. You could also use a templateManipulator to add the template (instead of a wrapper). angular-formly is very flexible.