I implement a field which input is "sanitised" via regex and if the input has chars that are not allowed by the regex the value of the exported property should not change. I made the the field to update the property on every input character. The value of the exported property updates as expected (checked via debugging) but the UI text control doesn't update the value and the wrong character stays in it. As per different articles I saw that the KVO/KVC pattern doesn't include in itself 2 way data binding. How I should circumvent that?