The main idea of Invalid is to be used when invalid data is entered within an input element and there is no practical use for invalid state of non input elements.
Could you please elaborate in what scenario an Invalid
state would be set to a RadButton for an example. If there is actually a use case scenario, where such property could be used for every control, you could add a feature request in our Ideas & Feedback Portal
with your suggestion and if the item receives enough votes, our developers team will consider implementing such functionality in one of our future releases.
Please let us know if we can assist you any further.
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