android - Endless RecyclerView with ProgressBar for pagination

Question

I am using a RecyclerView and fetching objects from an API in batches of ten. For pagination, I use EndlessRecyclerOnScrollListener.

It's all working properly. Now all that's left is to add a progress spinner at the bottom of the list while the next batch of objects is fetched by the API. Here is a screenshot of the Google Play Store app, showing a ProgressBar in what is surely a RecyclerView:

The problem is, neither the RecyclerView nor the EndlessRecyclerOnScrollListener have built-in support for showing a ProgressBar at the bottom while the next batch of objects is being fetched.

I have already seen the following answers:

1. Put an indeterminate ProgressBar as footer in a RecyclerView grid.

2. Adding items to Endless Scroll RecyclerView with ProgressBar at bottom.

I am not satisfied with those answers (both by the same person). This involves shoehorning a null object into the data-set midway while the user is scrolling and then taking it out after the next batch is delivered. It looks like a hack that sidesteps the main problem which may or may not work properly. And it causes a bit of jarring and distortion in the list

Using SwipeRefreshLayout is not a solution here. SwipeRefreshLayout involves pulling from the top to fetch the newest items, and it does not show a progress view anyway.

Can someone please provide a good solution for this? I am interested in knowing how Google has implemented this for their own apps (the Gmail app has it too). Are there any articles where this is shown in detail? All answers & comments will be appreciated. Thank you.

Some other references:

1. Pagination with RecyclerView. (Superb overview ...)

2. RecyclerView header and footer. (More of the same ...)

3. Endless RecyclerView with ProgressBar at bottom.

Answer 1

HERE IS SIMPLER AND CLEANER APPROACH.

Implement Endless Scrolling from this Codepath Guide and then follow the following steps.

1. Add progress bar under the RecyclerView.

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rv_movie_grid"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:paddingBottom="50dp"
        android:clipToPadding="false"
        android:background="@android:color/black"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

    </android.support.v7.widget.RecyclerView>

    <ProgressBar
        android:id="@+id/progressBar"
        style="?android:attr/progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:visibility="invisible"
        android:background="@android:color/transparent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

Here android:paddingBottom="50dp" and android:clipToPadding="false" are very important.

2. Get a reference to the progress bar.

progressBar = findViewById(R.id.progressBar);

3. Define methods to show and hide progress bar.

void showProgressView() {
    progressBar.setVisibility(View.VISIBLE);
}

void hideProgressView() {
    progressBar.setVisibility(View.INVISIBLE);
}