All geek questions in one place

Partitioning in RecyclerView

I have been working with lists for some time, and when I began to understand them, they come out with recycling. I have a simple working example containing all the elements. I would like to create sections in recyclerview using the same layout. For example, each section is filtered by data (breakfast, lunch, dinner). How do I create sections in recyclerview? If you need more information or if I think this is a bad question, I will update my question or put more code.

How I will filter adapters for breakfast, lunch and dinner:

FoodAdapter mAdapterBreakfast = new FoodAdapter(LogSet.filterBy("Breakfast"), R.layout.row, this); FoodAdapter mAdapterLunch = new FoodAdapter(LogSet.filterBy("Lunch"), R.layout.row, this); FoodAdapter mAdapterDinner = new FoodAdapter(LogSet.filterBy("Dinner"), R.layout.row, this);

How to get all the elements in the adapter:

 FoodAdapter mAdapter = new FoodAdapter(LogSet.all(), R.layout.row, this);

The following is a working example:

Adapter

 public class FoodAdapter extends RecyclerView.Adapter<FoodAdapter.ViewHolder> { private List<LogSet> meals; private int rowLayout; private Context mContext; View v; public FoodAdapter(List<LogSet> mMeals, int rowLayout, Context context) { this.meals = mMeals; this.rowLayout = rowLayout; this.mContext = context; } @Override public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) { v = LayoutInflater.from(viewGroup.getContext()).inflate(rowLayout, viewGroup, false); return new ViewHolder(v); } @Override public void onBindViewHolder(ViewHolder viewHolder, int i) { LogSet meal = meals.get(i); viewHolder.countryName.setText(meal.getLiftName()); } @Override public int getItemCount() { return meals == null ? 0 : meals.size(); } public static class ViewHolder extends RecyclerView.ViewHolder { public TextView countryName; public ViewHolder(View itemView) { super(itemView); countryName = (TextView) itemView.findViewById(R.id.foodName); } } }

Mainactivity

 public class MainActivity extends ActionBarActivity { RecyclerView mRecyclerView; Date mDate = new Date(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_testing_rec); mRecyclerView = (RecyclerView) findViewById(R.id.list); mRecyclerView.setLayoutManager(new LinearLayoutManager(this)); mRecyclerView.setItemAnimator(new DefaultItemAnimator()); FoodAdapter mAdapter = new FoodAdapter(LogSet.all(), R.layout.row, this); mRecyclerView.setAdapter(mAdapter); /* FoodAdapter mAdapterBreakfast = new FoodAdapter(LogSet.filterBy("Breakfast"), R.layout.row, this); FoodAdapter mAdapterLunch = new FoodAdapter(LogSet.filterBy("Lunch"), R.layout.row, this); FoodAdapter mAdapterDinner = new FoodAdapter(LogSet.filterBy("Dinner"), R.layout.row, this); */ } }

This is how I would send each list value to the adapter:

Adapter

 public class FoodAdapter extends RecyclerView.Adapter<FoodAdapter.ViewHolder> { private List<LogSet> meals; private List<LogSet> breakfast; private List<LogSet> lunch; private List<LogSet> dinner; private int rowLayout; private Context mContext; View v; public FoodAdapter(List<LogSet> mMeals, List<LogSet> mBreakfast, List<LogSet> mLunch, List<LogSet> mDinner, int rowLayout, Context context) { this.meals = mMeals; this.breakfast = mBreakfast; this.lunch = mLunch; this.dinner = mDinner; this.rowLayout = rowLayout; this.mContext = context; } @Override public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) { v = LayoutInflater.from(viewGroup.getContext()).inflate(rowLayout, viewGroup, false); return new ViewHolder(v); } @Override public void onBindViewHolder(ViewHolder viewHolder, int i) { LogSet meal = meals.get(i); viewHolder.countryName.setText(meal.getLiftName()); } public static class ViewHolder extends RecyclerView.ViewHolder { public TextView countryName; public ViewHolder(View itemView) { super(itemView); countryName = (TextView) itemView.findViewById(R.id.foodName); } } @Override public int getItemCount() { return meals == null ? 0 : meals.size(); } }

MainActivity minus all ()

 public class MainActivity extends ActionBarActivity { RecyclerView mRecyclerView; Date mDate = new Date(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_testing_rec); mRecyclerView = (RecyclerView) findViewById(R.id.list); mRecyclerView.setLayoutManager(new LinearLayoutManager(this)); mRecyclerView.setItemAnimator(new DefaultItemAnimator()); FoodAdapter mAdapter = new FoodAdapter(LogSet.all(), LogSet.filterBy("Breakfast"), LogSet.filterBy("Lunch"), LogSet.filterBy("Dinner"), R.layout.row, this); mRecyclerView.setAdapter(mAdapter); /* FoodAdapter mAdapterBreakfast = new FoodAdapter(LogSet.filterBy("Breakfast"), R.layout.row, this); FoodAdapter mAdapterLunch = new FoodAdapter(LogSet.filterBy("Lunch"), R.layout.row, this); FoodAdapter mAdapterDinner = new FoodAdapter(LogSet.filterBy("Dinner"), R.layout.row, this); */ } }

Again, how do I create sections in RecyclerView with breakfast, lunch and dinner?

+5
source share
1 answer

You can achieve this with only one adapter from this library: SectionedRecyclerViewAdapter .

First create a section class to group your items:

 class MySection extends StatelessSection { String title; List<LogSet> list; public MySection(String title, List<LogSet> list) { // call constructor with layout resources for this Section header, footer and items super(R.layout.section_header, R.layout.section_item); this.title = title; this.list = list; } @Override public int getContentItemsTotal() { return list.size(); // number of items of this section } @Override public RecyclerView.ViewHolder getItemViewHolder(View view) { // return a custom instance of ViewHolder for the items of this section return new MyItemViewHolder(view); } @Override public void onBindItemViewHolder(RecyclerView.ViewHolder holder, int position) { MyItemViewHolder itemHolder = (MyItemViewHolder) holder; // bind your view here itemHolder.tvItem.setText(list.get(position).getLiftName()); } @Override public RecyclerView.ViewHolder getHeaderViewHolder(View view) { return new SimpleHeaderViewHolder(view); } @Override public void onBindHeaderViewHolder(RecyclerView.ViewHolder holder) { MyHeaderViewHolder headerHolder = (MyHeaderViewHolder) holder; // bind your header view here headerHolder.tvItem.setText(title); } }

Then you set up RecyclerView with three instances of your section class (breakfast, lunch and dinner):

 // Create an instance of SectionedRecyclerViewAdapter SectionedRecyclerViewAdapter sectionAdapter = new SectionedRecyclerViewAdapter(); // Create your sections with the list of data MySection breakfastSection = new MySection("Breakfast", LogSet.filterBy("Breakfast")); MySection lunchSection = new MySection("Lunch", LogSet.filterBy("Lunch")); MySection dinnerSection = new MySection("Dinner", LogSet.filterBy("Dinner")); // Add your Sections to the adapter sectionAdapter.addSection(breakfastSection); sectionAdapter.addSection(lunchSection); sectionAdapter.addSection(dinnerSection); // Set up your RecyclerView with the SectionedRecyclerViewAdapter RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerview); recyclerView.setLayoutManager(new LinearLayoutManager(getContext())); recyclerView.setAdapter(sectionAdapter);
+2
source

Source: https://habr.com/ru/post/1215254/

More articles:


All Articles