I am new to Shopify and I want to learn how to create a Metafields Editor like SuperFields or Metafields Manager.
I searched a lot after relevant information but I had no luck so far. Can you provide me some examples and materials? If you have already created an application like this can you explain the process?
Any help is highly appreciated.
I usually don't answer open ended questions like this, but today GOT came out so I'm in a "sharing" mood. :D
We can't provide you any guides here because this is not a specific problem that can be answered. You are asking us how to paint a wall and create you a video on how to do so in the process instead of showing us what have you painted on your own in order to point out your mistakes. You can take this as constructive criticism with a grain of salt.
So ignoring the above comment here is a little freebie:
Pretty much every App in Shopify communicates with the REST API ( or GraphQL ) in order to achieve something. ( there are some exceptions here, don't jump on me with your guns community )
So when you ask how to create a metafield App, the simple answer is "You communicate with the REST Api". There is nothing more to it.
There is a metafield section in the Rest Api that provides information about this: https://help.shopify.com/en/api/reference/metafield
There is no specific guide how to create a Metafield App, but there are many guides on how to communicate with the REST Api. There are additional libraries ( official and community ones ) that makes this process even more painless.
So invest your time in reading how to properly communicate with the rest API and if you have a specific problem, you can ask it then here and we can try to help you, but not an open ended question like this one. ;)