android - How to know whether a RecyclerView / LinearLayoutManager is scrolled to top or bottom?

Question

Currently I am using the follow code to check whether SwipeRefreshLayout should be enabled.

private void laySwipeToggle() {
    if (mRecyclerView.getChildCount() == 0 || mRecyclerView.getChildAt(0).getTop() == 0) {
        mLaySwipe.setEnabled(true);
    } else {
        mLaySwipe.setEnabled(false);
    }
}

But here is the problem. When it's scrolled to another item's view's boundary mRecyclerView.getChildAt(0).getTop() also returns 0.

Is there something like RecyclerView.isScrolledToBottom() or RecyclerView.isScrolledToTop()?

EDIT: (mRecyclerView.getChildAt(0).getTop() == 0 && linearLayoutManager.findFirstVisibleItemPosition() == 0) kind of does the RecyclerView.isScrolledToTop(), but what about RecyclerView.isScrolledToBottom()?

Answer 1

The solution is in the layout manager.

LinearLayoutManager layoutManager = new LinearLayoutManager(this);

// Add this to your Recycler view
recyclerView.setLayoutManager(layoutManager);

// To check if at the top of recycler view
if(layoutManager.firstCompletelyVisibleItemPosition()==0){
    // Its at top
}

// To check if at the bottom of recycler view
if(layoutManager.lastCompletelyVisibleItemPosition()==data.size()-1){
    // Its at bottom
}

EDIT

In case your item size is larger than the screen use the following to detect the top event.

RecyclerView recyclerView = (RecyclerView) view;
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();

int pos = linearLayoutManager.findFirstVisibleItemPosition();

if(linearLayoutManager.findViewByPosition(pos).getTop()==0 && pos==0){
    return true;
}

PS: Actually, if you place the RecyclerView directly inside the SwipeRefreshview you wouldn't need to do this