In the context of this exercise, how does this update the text on every change?
The way this works is generally as follows.
Every time we change the input of the text field, whether by adding or deleting some text, it will trigger the
onChange attribute’s function,
handleUserInput(). When this function is invoked, it will update the state of the component to the current value of the text field using
setState(). Any time
setState() is called for a component, it will trigger a call to the
render() method, which will re-display the text to the latest value of the text field.