How can I create a android recyclerView which shows firebase realtime database data with different model class?

Question

I want a recyclerView that fetches data from Firebase real-time database. But the database nodes contain data with different model classes. Now how can I detect which model class I need to use depending on the dataSnapshot.

Answer 1

You don't need multiple adapter you need multiple ViewHolders, check this How to create RecyclerView with multiple view type?

@Override
public int getItemViewType(int position) {
 //... if item is instance of ModelA return 0
 //... if item is instance of ModelB return 1
}

Then in onCreateViewHolder

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
     switch (viewType) {
         case 0: return new ViewHolder0(...);
         case 1: return new ViewHolder1(...);
         ...
     }
}

and in onBindViewHolder

@Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, final int position) {
    switch (holder.getItemViewType()) {
        case 0:
            ViewHolder0 viewHolder0 = (ViewHolder0)holder;
            ...
            break;

        case 1:
            ViewHolder1 viewHolder1 = (ViewHolder1)holder;
            ...
            break;
    }
}

Answer 2

If by multi-adapter you mean to display more than one type of recyclerViewItem in the recyclerView, then just override getItemViewType method in your adapter class, and then in onCreateViewHolderHolder you can inflate the recyclerItemLayouts accordingly by checking viewType argument.

Check this out for more info: https://www.journaldev.com/12372/android-recyclerview-example