I am working on a feed-style app, where a user has a lot of posts in a scrollable RecyclerView. I have another Activity that the user goes to that is essentially a CalendarView, and the user can select a date from it to navigate to in the RecyclerView. More on this later.
Each item in the RecyclerView is a Post. The Post class looks like this:
public abstract class Post implements Comparable<Post> {
public String userId;
public Date date;
public Post() {
}
protected Post(String userId, Date date) {
this.userId = userId;
this.date = date;
}
@Override
public int compareTo(@NonNull Post o) {
return date.compareTo(o.date);
}
}
Note that all of the Posts are sorted by their dates inside of the RecyclerView. They are sorted so that the most recent posts are at the top.
Inside of my MainActivity, I have the following code to set up the RecyclerView:
myRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
myRecyclerView.setHasFixedSize(false);
layoutManager = new LinearLayoutManager(this);
myRecyclerView.setLayoutManager(layoutManager);
adapter = new SocialJournalAdapter(posts, this);
myRecyclerView.setAdapter(adapter);
Where myRecyclerView is a RecyclerView, adapter is a RecyclerView.Adapter, layoutManager is a RecyclerView.LayoutManager, and posts is a List<Post>.
Assume that the date that is chosen inside of the other calendar Activity isn't necessarily the date of an actual post, but could be any date. So, if I have posts dated Jan 1, 2017 and Mar 15, 2017, and I choose February 1, 2017, the RecyclerView will put the post dated Mar 15, 2017 at the top, since it is the first post after that date.
From this answer, I believe that once I have the index, I can scroll to it with layoutManager.scrollToPositionWithOffset(desiredIndex, 0);, but I haven't tested this out, and I don't really know how to find the desiredIndex
Let me know if you need any other information or more of my code.
