exercise

Exercise

TodoFooter

1. Open TodoFooter and write a TodoFooterProps interface. It should include two values, a function and an object. Assign this interface to props like this: (props: TodoFooterProps)
2. Write an _onClick function that calls props.clear.

   Since TodoFooter is not a class the _onClick needs to be declared as a const, and placed before the return.

3. Add _onClick to the button's onClick. You won't need to use this since this isn't a class.

   We can't assign our clear function directly to onClick. We always need to create a function that calls our callbacks. () => props.clear()

4. Test out this functionality. Check a few todos complete and click the Clear Completed button

TodoHeader

1. Open TodoHeader and write TodoHeaderProps which will include 3 values. Replace the first any with this interface.
2. This component also has state. Write TodoHeaderState (there's just one item), and add this where the second any was.
3. Add _onFilter to each of the filter buttons

   Note that we can't add new parameters to onClick, but we can pull information from the event target!

4. Write an _onAdd method that calls addTodo on the current labelInput, then sets the labelInput in state to an empty string
5. Call _onAdd from the submit button
6. Check out this new functionality! We can now add and filter todos!