ContributionsView.java

package me.ccrama.redditslide.Fragments;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import me.ccrama.redditslide.Activities.Profile;
import me.ccrama.redditslide.Adapters.ContributionAdapter;
import me.ccrama.redditslide.Adapters.ContributionPosts;
import me.ccrama.redditslide.Adapters.ContributionPostsSaved;
import me.ccrama.redditslide.Constants;
import me.ccrama.redditslide.R;
import me.ccrama.redditslide.Views.CatchStaggeredGridLayoutManager;
import me.ccrama.redditslide.Views.PreCachingLayoutManager;
import me.ccrama.redditslide.Visuals.Palette;
import me.ccrama.redditslide.handler.ToolbarScrollHideHandler;

public class ContributionsView extends Fragment {


    private int totalItemCount;
    private int visibleItemCount;
    private int pastVisiblesItems;
    private ContributionAdapter adapter;
    private ContributionPosts posts;
    private String id;
    private String where;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View v = inflater.inflate(R.layout.fragment_verticalcontent, container, false);

        final RecyclerView rv = ((RecyclerView) v.findViewById(R.id.vertical_content));
        final PreCachingLayoutManager mLayoutManager;

        mLayoutManager = new PreCachingLayoutManager(getContext());


        rv.setLayoutManager(mLayoutManager);
        rv.setItemViewCacheSize(2);
        v.findViewById(R.id.post_floating_action_button).setVisibility(View.GONE);
        final SwipeRefreshLayout mSwipeRefreshLayout = (SwipeRefreshLayout) v.findViewById(R.id.activity_main_swipe_refresh_layout);

        mSwipeRefreshLayout.setColorSchemeColors(Palette.getColors(id, getActivity()));

        //If we use 'findViewById(R.id.header).getMeasuredHeight()', 0 is always returned.
        //So, we estimate the height of the header in dp
        mSwipeRefreshLayout.setProgressViewOffset(false,
                Constants.TAB_HEADER_VIEW_OFFSET - Constants.PTR_OFFSET_TOP,
                Constants.TAB_HEADER_VIEW_OFFSET + Constants.PTR_OFFSET_BOTTOM);

        mSwipeRefreshLayout.post(new Runnable() {
            @Override
            public void run() {
                mSwipeRefreshLayout.setRefreshing(true);
            }
        });

        if (where.equals("saved") && getActivity() instanceof Profile)
            posts = new ContributionPostsSaved(id, where, ((Profile) getActivity()).category);
        else
            posts = new ContributionPosts(id, where);

        //noinspection StringEquality
        if (where == "hidden") adapter = new ContributionAdapter(getActivity(), posts, rv, true);
        else adapter = new ContributionAdapter(getActivity(), posts, rv);
        rv.setAdapter(adapter);

        posts.bindAdapter(adapter, mSwipeRefreshLayout);
        //TODO catch errors
        mSwipeRefreshLayout.setOnRefreshListener(
                new SwipeRefreshLayout.OnRefreshListener() {
                    @Override
                    public void onRefresh() {
                        posts.loadMore(adapter, id, true);
                        //TODO catch errors
                    }
                }
        );
        rv.addOnScrollListener(new ToolbarScrollHideHandler((Toolbar) getActivity().findViewById(R.id.toolbar), getActivity().findViewById(R.id.header)) {
            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                visibleItemCount = rv.getLayoutManager().getChildCount();
                totalItemCount = rv.getLayoutManager().getItemCount();
                if (rv.getLayoutManager() instanceof PreCachingLayoutManager) {
                    pastVisiblesItems = ((PreCachingLayoutManager) rv.getLayoutManager()).findFirstVisibleItemPosition();
                } else {
                    int[] firstVisibleItems = null;
                    firstVisibleItems = ((CatchStaggeredGridLayoutManager) rv.getLayoutManager()).findFirstVisibleItemPositions(firstVisibleItems);
                    if (firstVisibleItems != null && firstVisibleItems.length > 0) {
                        pastVisiblesItems = firstVisibleItems[0];
                    }
                }

                if (!posts.loading) {
                    if ((visibleItemCount + pastVisiblesItems) + 5 >= totalItemCount && !posts.nomore) {
                        posts.loading = true;
                        posts.loadMore(adapter, id, false);
                    }
                }
            }
        });
        return v;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Bundle bundle = this.getArguments();
        id = bundle.getString("id", "");
        where = bundle.getString("where", "");

    }


}