Updating state on props change in React Form

Question

I am having trouble with a React form and managing the state properly. I have a time input field in a form (in a modal). The initial value is set as a state variable in

Answer 1

componentWillReceiveProps is being deprecated because using it "often leads to bugs and inconsistencies".

If something changes from the outside, consider resetting the child component entirely with key.

Providing a key prop to the child component makes sure that whenever the value of key changes from the outside, this component is re-rendered. E.g.,

On its performance:

While this may sound slow, the performance difference is usually insignificant. Using a key can even be faster if the components have heavy logic that runs on updates since diffing gets bypassed for that subtree.