如何获取特定的 recyclerview 项目类别并将其传递给新 activity

Question

我创建了一个电影应用程序，该应用程序几乎完成了，但有一个缺点，即如果用户单击一个特定类别，他们必须查看该特定类别的所有详细信息。我是 android 的新手，所以我不知道如何实现它。其中一个告诉我们可以使用 sql fetch 但我使用了 retro fit 所以我不想将我的后端从 json 更改为 sql .

我试过类似的问题，但无法上传我的主要 activity、适配器模型 class 和 JSON 文件数据 Mainacivity.Java

package com.example.movieapp;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.SearchView;
import androidx.core.view.MenuItemCompat;
import androidx.core.widget.NestedScrollView;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import androidx.viewpager.widget.ViewPager;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.provider.Settings;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.AdapterView;
import android.widget.Filter;

import com.example.movieapp.adapter.BannerMoviesPagerAdapter;
import com.example.movieapp.adapter.ItemRecyclerAdapter;
import com.example.movieapp.adapter.MainRecyclerAdapter;
import com.example.movieapp.listener.OnItemClickLIstener;
import com.example.movieapp.model.AllCategory;
import com.example.movieapp.model.BannerMovies;
import com.example.movieapp.model.CategoryItemList;
import com.example.movieapp.retrofit.RetrofitClient;
import com.google.android.material.appbar.AppBarLayout;
import com.google.android.material.tabs.TabLayout;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.disposables.CompositeDisposable;
import io.reactivex.observers.DisposableObserver;
import io.reactivex.schedulers.Schedulers;
import retrofit2.Retrofit;

public class MainActivity extends AppCompatActivity  {

    BannerMoviesPagerAdapter bannerMoviesPagerAdapter;
    TabLayout IndicatorTab,categoryTab;
    ViewPager bannerMoviesViewpager;
    List<BannerMovies> homeBannerList;
    List<BannerMovies> tvBannerList;
    List<BannerMovies> songBannerList;
    List<BannerMovies> audioBannerList;
    NestedScrollView nestedScrollView;
    AppBarLayout appBarLayout;

    MainRecyclerAdapter mainRecyclerAdapter;
    ItemRecyclerAdapter itemRecyclerAdapter;
    RecyclerView mainRecycler;
    List<AllCategory> allCategoryList;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // Adding this line will prevent taking screenshot in your app
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_SECURE,
                WindowManager.LayoutParams.FLAG_SECURE);
        IndicatorTab =findViewById(R.id.tab_indicator);
        categoryTab =findViewById(R.id.tabLayout);
        nestedScrollView =findViewById(R.id.nested_scroll);
        appBarLayout =findViewById(R.id.appbar);
        homeBannerList=new ArrayList<>();
        tvBannerList=new ArrayList<>();
        songBannerList=new ArrayList<>();
        audioBannerList=new ArrayList<>();
        getBannerData();
        getAllMoviesData(1);




        categoryTab.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                switch (tab.getPosition()){
                    case 1:

                        setBannerMoviesPagerAdapter(tvBannerList);
                        getAllMoviesData(2);



                        return;
                    case 2:

                        setBannerMoviesPagerAdapter(songBannerList);
                        getAllMoviesData(3);

                        return;

                        case 3:

                            setBannerMoviesPagerAdapter(audioBannerList);
                            getAllMoviesData(4);
                          return;
                    default:

                        setBannerMoviesPagerAdapter(homeBannerList);
                        getAllMoviesData(1);


                }

            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

            }
        });


        //titles
        allCategoryList=new ArrayList<>();


    }

    private void setBannerMoviesPagerAdapter(List<BannerMovies> bannerMoviesList) {
        bannerMoviesViewpager = findViewById(R.id.banner_viewPager);
        bannerMoviesPagerAdapter = new BannerMoviesPagerAdapter(this, bannerMoviesList);
        bannerMoviesViewpager.setAdapter(bannerMoviesPagerAdapter);
        IndicatorTab.setupWithViewPager(bannerMoviesViewpager);


    }


public void setMainRecycler(List<AllCategory>allCategoryList){
        mainRecycler=findViewById(R.id.main_recycler);
        RecyclerView.LayoutManager layoutManager= new LinearLayoutManager(this,RecyclerView.VERTICAL,false);
mainRecycler.setLayoutManager(layoutManager);
mainRecyclerAdapter =new MainRecyclerAdapter(this,allCategoryList);
mainRecycler.setAdapter(mainRecyclerAdapter);
    }
    private void getBannerData()
    {
        CompositeDisposable compositeDisposable = new CompositeDisposable();
        compositeDisposable.add(RetrofitClient.getRetroFitClient().getAllBanners()
                                 .subscribeOn(Schedulers.io())
                                 .observeOn(AndroidSchedulers.mainThread())
                                     .subscribeWith(new DisposableObserver<List<BannerMovies>>() {
                                         @Override
                                         public void onNext(List<BannerMovies> bannerMovies) {
                                            for ( int i=0; i < bannerMovies.size(); i++ )
                                            {
                                                if(bannerMovies.get(i).getBannerCategoryId().toString().equals("1"))
                                                {
                                                    homeBannerList.add(bannerMovies.get(i));

                                                } else if (bannerMovies.get(i).getBannerCategoryId().toString().equals("2"))
                                                {
                                                    tvBannerList.add(bannerMovies.get(i));

                                                }  else if (bannerMovies.get(i).getBannerCategoryId().toString().equals("3"))
                                                {
                                                    songBannerList.add(bannerMovies.get(i));

                                                } else if  (bannerMovies.get(i).getBannerCategoryId().toString().equals("4"))
                                                {
                                                    audioBannerList.add(bannerMovies.get(i));

                                                }
                                                else
                                                {
                                                    homeBannerList.add(bannerMovies.get(i));
                                                }



                                            }
                                         }

                                         @Override
                                         public void onError(Throwable e) {
                                             Log.d("bannerData",""+e);
                                         }

                                         @Override
                                         public void onComplete() {
                                             setBannerMoviesPagerAdapter(homeBannerList);
                                         }
                                     })

        );
    }

    private void getAllMoviesData(Integer categoryId)
    {
        CompositeDisposable compositeDisposable = new CompositeDisposable();
        compositeDisposable.add(RetrofitClient.getRetroFitClient().getAllCategoryMovies(categoryId)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribeWith(new DisposableObserver<List<AllCategory>>() {
                    @Override
                    public void onNext(List<AllCategory> allCategoryList) {
                        for ( int i=0; i < allCategoryList.size(); i++ )
                        {

                        }
                        setMainRecycler(allCategoryList);



                    }

                    @Override
                    public void onError(Throwable e) {
                        Log.d("bannerData",""+e);
                    }

                    @Override
                    public void onComplete() {

                    }
                })

        );
    }



}

Itemrecycleradpater

package com.example.movieapp.adapter;

import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.ImageView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.Glide;
import com.example.movieapp.MovieDetails;
import com.example.movieapp.R;
import com.example.movieapp.model.CategoryItemList;

import java.util.ArrayList;
import java.util.List;

public class ItemRecyclerAdapter extends RecyclerView.Adapter<ItemRecyclerAdapter.ItemViewHolder> implements Filterable {
    Context context;
    private List<CategoryItemList> categoryItemList;
     private List<CategoryItemList>allCategoryListFull;

    public ItemRecyclerAdapter(Context context, List<CategoryItemList> categoryItemList) {
        this.context = context;
        this.categoryItemList = categoryItemList;
        allCategoryListFull = new ArrayList<>(categoryItemList);
    }

    @NonNull
    @Override
    public ItemViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        return new ItemViewHolder(LayoutInflater.from(context).inflate(R.layout.cardview_movies,parent,false));
    }

    @Override
    public void onBindViewHolder(@NonNull ItemViewHolder holder, final int position) {

        Glide.with(context).load(categoryItemList.get(position).getSmallThumb()).placeholder(R.drawable.image12).into(holder.image_item);


       holder.image_item.setOnClickListener(view -> {
               Intent i = new Intent(context, MovieDetails.class);
               i.putExtra("movieId",categoryItemList.get(position).getId());
               i.putExtra("movieName",categoryItemList.get(position).getMovieName());
           i.putExtra("smallThumb",categoryItemList.get(position).getSmallThumb());
               i.putExtra("movieImageUrl",categoryItemList.get(position).getImageUrl());
               i.putExtra("movieFile",categoryItemList.get(position).getFileUrl());
           i.putExtra("MovieDesc",categoryItemList.get(position).getMovieDesc());
           i.putExtra("Language",categoryItemList.get(position).getLanguage());
           i.putExtra("Singers",categoryItemList.get(position).getSingers());
           i.putExtra("TrailerUrl",categoryItemList.get(position).getTrailerUrl());
               context.startActivity(i);

       });

    }


    @Override
    public int getItemCount() {
        return categoryItemList.size();
    }


    @Override
    public Filter getFilter() {
        return filterNew;
    }

    private Filter filterNew = new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            List<CategoryItemList> filteredList = new ArrayList<>();
            if(constraint == null || constraint.length() ==0){
                filteredList.addAll(allCategoryListFull);
            }
            else{
                String filterPattern = constraint.toString().toLowerCase().trim();
                for(CategoryItemList item: allCategoryListFull)
                {
                    if(item.getMovieName().toLowerCase().contains(filterPattern))
                    {
                        filteredList.add(item);
                    }
                }

            }

            FilterResults results  = new FilterResults();
            results.values = filteredList;
            return results;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {

            categoryItemList.clear();
            categoryItemList.addAll((List)results.values);
            notifyDataSetChanged();

        }
    };

    public static final class ItemViewHolder extends RecyclerView.ViewHolder
    {
        ImageView image_item;

        public ItemViewHolder(@NonNull View itemView) {
            super(itemView);
            image_item=itemView.findViewById(R.id.image_item);
        }
    }

}

package com.example.movieapp.adapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.example.movieapp.R;
import com.example.movieapp.model.AllCategory;
import com.example.movieapp.model.CategoryItemList;

import java.util.List;


public class MainRecyclerAdapter extends RecyclerView.Adapter<MainRecyclerAdapter.MainViewHolder> {

    Context context;
    private List<AllCategory> allCategoryList;


    public MainRecyclerAdapter(Context context, List<AllCategory> allCategoryList) {
        this.context = context;
        this.allCategoryList = allCategoryList;
    }

    @NonNull
    @Override
    public MainViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        return new MainViewHolder(LayoutInflater.from(context).inflate(R.layout.main_recycler_row_item, parent, false));

    }

    @Override
    public void onBindViewHolder(@NonNull MainViewHolder holder, int position) {
        holder.categoryName.setText(allCategoryList.get(position).getCategoryTitle());
        setItemRecycler(holder.itemRecycler,allCategoryList.get(position).getCategoryItemList());


    }

    @Override
    public int getItemCount() {
        return allCategoryList.size();
    }


    public static final class MainViewHolder extends RecyclerView.ViewHolder {

        TextView categoryName;
        RecyclerView itemRecycler;


        public MainViewHolder(@NonNull View itemView) {
            super(itemView);
            categoryName = itemView.findViewById(R.id.item_category);
            itemRecycler = itemView.findViewById(R.id.item_recycler);

        }
    }

    private void setItemRecycler(RecyclerView recyclerview, List<CategoryItemList> categoryItemList) {

        ItemRecyclerAdapter itemRecyclerAdapter = new ItemRecyclerAdapter(context,categoryItemList);
        recyclerview.setLayoutManager(new LinearLayoutManager(context,RecyclerView.HORIZONTAL,false));
        //recyclerview.setLayoutManager(new GridLayoutManager(context,3));
        recyclerview.setAdapter(itemRecyclerAdapter);

    }
}

Answer 1

package com.example.movieapp.adapter;

import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.example.movieapp.R;
import com.example.movieapp.model.AllCategory;
import com.example.movieapp.model.CategoryItemList;

import java.util.List;


public class MainRecyclerAdapter extends RecyclerView.Adapter<MainRecyclerAdapter.MainViewHolder> {

    Context context;
    private List<AllCategory> allCategoryList;
    
    public MainRecyclerAdapter(Context context, List<AllCategory> allCategoryList) {
        this.context = context;
        this.allCategoryList = allCategoryList;
    }

    @NonNull
    @Override
    public MainViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        return new MainViewHolder(LayoutInflater.from(context).inflate(R.layout.main_recycler_row_item, parent, false));
    }

    @Override
    public void onBindViewHolder(@NonNull MainViewHolder holder, int position) {

        // Here is your call to an individual item or object like category name
        holder.categoryName.setText(allCategoryList.get(position).getCategoryTitle());

        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //Stuff to open new activity
                List<CategoryItemList> categoryItemList = allCategoryList.get(position).getCategoryItemList()

                Intent i = new Intent(context, MopvieList.class); //New screen
                i.putExtra("itemList", categoryItemList); //passing serializable object
                //NOTE: CategoryItemList class must implement Serializable
            }
        });

        setItemRecycler(holder.itemRecycler, allCategoryList.get(position).getCategoryItemList());
    }

    @Override
    public int getItemCount() {
        return allCategoryList.size();
    }
    
    public static final class MainViewHolder extends RecyclerView.ViewHolder {

        TextView categoryName;
        RecyclerView itemRecycler;
        
        public MainViewHolder(@NonNull View itemView) {
            super(itemView);
            categoryName = itemView.findViewById(R.id.item_category);
            itemRecycler = itemView.findViewById(R.id.item_recycler);

        }
    }

    private void setItemRecycler(RecyclerView recyclerview, List<CategoryItemList> categoryItemList) {
        ItemRecyclerAdapter itemRecyclerAdapter = new ItemRecyclerAdapter(context, categoryItemList);
        recyclerview.setLayoutManager(new LinearLayoutManager(context, RecyclerView.HORIZONTAL, false));
        //recyclerview.setLayoutManager(new GridLayoutManager(context,3));
        recyclerview.setAdapter(itemRecyclerAdapter);
    }
}

Answer 2

 holder.button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            List<CategoryItemList> categoryItemList = allCategoryList.get(position).getCategoryItemList();
            Intent i = new Intent(context, MovieCat.class); //my activity for showing all category
            i.putExtra("itemList", (Serializable) categoryItemList);
            context.startActivity(i);
        }

public class AllCategory implements Serializable {}// as instructed made it serializable.

public class MovieCat extends AppCompatActivity  {
    TextView MovieCat;
    String movieNameCat;

    ArrayList<CategoryItemList> catItems;
    RecyclerView recyclerView;
    MainRecyclerAdapter mainRecyclerAdapter;

Button button;
    String cat; //for item_list intent 
    String catId;// for intent
    int categoryId;// for get all movies data
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_movie_cat);
        MovieCat = findViewById(R.id.textView2);
        movieNameCat = getIntent().getStringExtra("categoryTitle");
        cat = getIntent().getStringExtra("itemList");
        button=findViewById(R.id.view_all_btn);
        MovieCat.setText(movieNameCat);
      catId = getIntent().getStringExtra("categoryId"); getAllMoviesData(categoryId);
        getAllMoviesData(categoryId);
    }




    private void getAllMoviesData(int categoryId) {
        {
            CompositeDisposable compositeDisposable = new CompositeDisposable();
            compositeDisposable.add(RetrofitClient.getRetroFitClient().getAllCategoryMovies(categoryId)
                    .subscribeOn(Schedulers.io())
                    .observeOn(AndroidSchedulers.mainThread())
                    .subscribeWith(new DisposableObserver<List<AllCategory>>() {
                        @Override
                        public void onNext(List<AllCategory> itemList) {
                            for (int i = 0; i < itemList.size(); i++) {
                                setMainRecycler(itemList);

                            }
                        }
                        @Override
                        public void onError(Throwable e) {
                            Log.d("bannerData", "" + e);
                        }
                        @Override
                        public void onComplete() {
                        }
                    })

            );
        }
    }

    public void setMainRecycler(List<AllCategory> catItems) {
        recyclerView = findViewById(R.id.item_cycle);
        RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this, RecyclerView.VERTICAL, false);
        recyclerView.setLayoutManager(layoutManager);
        mainRecyclerAdapter = new MainRecyclerAdapter(this, catItems);
        recyclerView.setAdapter(mainRecyclerAdapter);


    }

更新了我的代码 @KGeeks

如何获取特定的 recyclerview 项目类别并将其传递给新 activity

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android-studio

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