Console warning: prop amPm is required but not set in Hour12Input

[emilyuhde]

When using the TimePicker in dev mode, I'm seeing a console warning.

Warning: Failed prop type: The prop amPm is marked as required in Hour12Input, but its value is null. in Hour12Input (created by TimeInput) in TimeInput (created by TimePicker) in div (created by TimePicker)

I only seem to be seeing this warning when I use hooks to manage the state of the TimePicker component: https://gist.github.com/emilyuhde/ded5df5a5b54baeb981403148b9c892a

I don't see the warning when I use a stateful class: https://gist.github.com/emilyuhde/8275a185ca2ca649a30dc3fb6df9be88

[emilyuhde]

I think I see the issue, the react dependency is "react": "^16.7.0". Are there plans to update the dependency to 16.8.x soon?

[wojtekmaj]

^16.7.0 signifies compatibility with >=16.7.0; <17.0.0, so with 16.8.0, too. I don't think that is the cause!

[wojtekmaj]

Hmmmm, I tested your code and I don't see the warning you're seeing. The only thing I see is that you use useState() without default prop, which causes it to be undefined initially, which is not the case in your class component. So maybe that's the problem?

[emilyuhde]

Thanks for looking at this. I was looking at this issue some more yesterday and I think I figured out what's actually causing it. If I initialize the value to null, and the TimePicker is in 12 hour format, that seems to be what's causing the console warning to appear. I think the use of a class component with state vs using hooks was just a red herring and isn't actually causing an issue. That's why I closed this issue and created #31 since that console warning isn't wrong, it's just annoying when I want to intentionally initialize the value to null so that the TimePicker will display the placeholder --:-- -- state.

[yaniiv]

+1, having the exact same issue as emily. I can confirm that it has to do with initializing the value to null. Not a big issue, but it would be helpful to add a blurb in the readme!

[wojtekmaj]

@yantonsoup This has already been fixed and will land in the next release.