How to know when the Recyler view in android is done inflating items?-CodePudding

The requirement is that I want to highlight the first item of recycler view on my screen. I am using recyclerView.getChildAt(0) to get the first item but how do I figure out whether the first item of recycler view is available or not? I can't directly call getChildAt() because in some cases the network response might be slow and getChildAt(0) may return null.

Tried using onGlobalLayoutListener, didn't work.

CodePudding user response：

Why not highlight it in onBindViewHolder of the adapter? You can check if the item is at position 0 or not and highlight accordingly. The adapter is responsible for the views anyway. You don't need to handle it outside the adapter class.

override fun onBindViewHolder(holder: YourHolderType, position: Int) {
    //...

    if (position == 0) {
        // highlight the view in the holder
    } else {
        // de-highlight the view
    }
}

CodePudding user response：

To find count of total items (instead of child-views), check like:

if (recyclerView.getAdapter().getItemCount() > 0) {
    // Do something with items...
} else {
    // No items, do something else?
}

Listener style

In case you are not sure when to do above check:

import androidx.recyclerview.widget.LinearLayoutManager;

// ...

recyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false){
    @Override
    public void onLayoutCompleted(RecyclerView.State state) {
        super.onLayoutCompleted(state);

        // Your check should be here...
    }
);