Android Question Sign key data

[devmobile]

When we make sign key for our app,after create,it give md5 and sha1 and other key that exist in key file to us
My question is Maybe hacker get this keys from my app?

 

[devmobile]

I found my answer in below link
https://www.b4x.com/android/forum/threads/get-the-apk-signature-at-runtime.70490/#post-447574