I am using Cloud Firestore to make my own E-commerce App. I want my category collection to contain many categories like shoes, clothes, watches, etc and in each of those categories there are different products so I can click on that category and show all the related products on my app, please guide me or if you have another way to do this, please show me.

Category and Products

CodePudding user response：

According to your comment:

just tens, this is just my personal project.

Since you only have tens of category names, then the best option that you have is to store them in a single document, in an array type field. Then each product document should contain a field where you have to specify the category. Your schema should look like this:

Firestore-root
  |
  --- shop (collection)
  |    |
  |    --- category (document)
  |          |
  |          --- names: ["shoes", "clothes", "watches"]
  |
  --- products (collection)
       |
       --- $productId (document)
             |
             --- name: "Nike Air Jordan"
             |
             --- category: "shoes"

To be able to display the category names, you should simply read the array that exists in the document, and display the content into a ListView, or even better, in a RecyclerView.

Furthermore, if you need to click on a particular category, and go forward to display only the products that correspond to a specific category, then you should use the following query:

FirebaseFirestore db = FirebaseFirestore.getInstance();
Query queryByCategory = db.collection("products").whereEqualTo("category", "shoes");

For displaying the products you might consider reading my answer from the following post:

How to display data from Firestore in a RecyclerView with Android?

The following article might also help you read the data with the use of the Firebase-UI library:

• How to read data from Cloud Firestore using get()?