Recyclerview item onClick 从 Main Activity Fragment 打开一个 Fragment

Question

我在 MainActivity 上有 4-5 个片段，在主机片段上我有一个 recyclerview。在回收器的每个项目上，我必须从另外 4 个片段中打开一个片段并杀死放置回收器的当前片段。我无法做到这一点。

这是我的 MainActivity 放置所有片段的地方，宿主片段是放置回收器的 homefragment，我想在单击第 0 个项目时从 homefragment 移动到另一个片段

public class MainActivity extends AppCompatActivity {

private AppBarConfiguration mAppBarConfiguration;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);


    DrawerLayout drawer = findViewById(R.id.drawer_layout);
    NavigationView navigationView = findViewById(R.id.nav_view);
    // Passing each menu ID as a set of Ids because each
    // menu should be considered as top level destinations.
    mAppBarConfiguration = new AppBarConfiguration.Builder(
            R.id.nav_home, R.id.nav_house_business, R.id.nav_committees,
            R.id.nav_senators, R.id.nav_about_senate, R.id.nav_publications, R.id.nav_media_center
            , R.id.nav_get_involved)
            .setDrawerLayout(drawer)
            .build();
    NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
    NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
    NavigationUI.setupWithNavController(navigationView, navController);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onSupportNavigateUp() {
    NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
    return NavigationUI.navigateUp(navController, mAppBarConfiguration)
            || super.onSupportNavigateUp();
}

}

这是我的宿主片段

public class HomeFragment extends Fragment {

private HomeViewModel homeViewModel;
TextView ticker ;

public View onCreateView(@NonNull LayoutInflater inflater,
                         ViewGroup container, Bundle savedInstanceState) {
    homeViewModel =
            ViewModelProviders.of(this).get(HomeViewModel.class);
    final View root = inflater.inflate(R.layout.fragment_home, container, false);

    MyListData[] myListData = new MyListData[] {
            new MyListData("Order of the Day", R.drawable.orders),
            new MyListData("Bills", R.drawable.bills),
            new MyListData("Delete", R.drawable.orders),
            new MyListData("Dialer", R.drawable.bills),
            new MyListData("Alert", R.drawable.orders),
            new MyListData("Map", R.drawable.bills),
            new MyListData("Email", R.drawable.orders),
            new MyListData("Info", R.drawable.bills),
            new MyListData("Delete", android.R.drawable.ic_delete),
            new MyListData("Dialer", android.R.drawable.ic_dialog_dialer),
            new MyListData("Alert", android.R.drawable.ic_dialog_alert),
            new MyListData("Map", android.R.drawable.ic_dialog_map),
    };



    RecyclerView recyclerView = root.findViewById(R.id.recyclerView);
    MyListAdapter adapter = new MyListAdapter(myListData);
    recyclerView.setHasFixedSize(true);
    RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(getContext(), 2);
    recyclerView.setLayoutManager(mLayoutManager);
    //recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
    recyclerView.setAdapter(adapter);

    return root;
}

}

这是我的列表适配器

public class MyListAdapter extends RecyclerView.Adapter<MyListAdapter.ViewHolder>{
private MyListData[] listdata;

// RecyclerView recyclerView;
public MyListAdapter(MyListData[] listdata) {
    this.listdata = listdata;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
    View listItem= layoutInflater.inflate(R.layout.list_item, parent, false);
    ViewHolder viewHolder = new ViewHolder(listItem);

    return viewHolder;
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    final MyListData myListData = listdata[position];
    holder.textView.setText(listdata[position].getDescription());
    holder.imageView.setImageResource(listdata[position].getImgId());


    switch(position)
    {
        case 0 :
        {
            holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
                @Override

                public void onClick(View view) {

                    Fragment someFragment = new Orderofday();
                    FragmentTransaction transaction = getFragmentManager().beginTransaction();
                    transaction.replace(R.id.nav_host_fragment, someFragment ); // give your fragment container id in first parameter
                    transaction.addToBackStack(null);  // if written, this transaction will be added to backstack
                    transaction.commit();
                }
            });
        }
        case 1 :
        {
            holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
                @Override

                public void onClick(View view) {
                    Toast.makeText(view.getContext(),"click on item: "+myListData.getDescription(),Toast.LENGTH_LONG).show();


                }
            });
        }
        case 2 :
        {
            holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
                @Override

                public void onClick(View view) {
                    Toast.makeText(view.getContext(),"click on item: "+myListData.getDescription(),Toast.LENGTH_LONG).show();


                }
            });
        }
        case 3 :
        {
            holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
                @Override

                public void onClick(View view) {
                    Toast.makeText(view.getContext(),"click on item: "+myListData.getDescription(),Toast.LENGTH_LONG).show();


                }
            });
        }
        case 4 :
        {
            holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
                @Override

                public void onClick(View view) {
                    Toast.makeText(view.getContext(),"click on item: "+myListData.getDescription(),Toast.LENGTH_LONG).show();


                }
            });
        }
        case 5 :
        {
            holder.relativeLayout.setOnClickListener(new View.OnClickListener() {
                @Override

                public void onClick(View view) {
                    Toast.makeText(view.getContext(),"click on item: "+myListData.getDescription(),Toast.LENGTH_LONG).show();


                }
            });
        }

        default:
        {
            break;
        }

    }


}


@Override
public int getItemCount() {
    return listdata.length;
}

public static class ViewHolder extends RecyclerView.ViewHolder {
    public ImageView imageView;
    public TextView textView;
    public RelativeLayout relativeLayout;
    public ViewHolder(View itemView) {
        super(itemView);
        this.imageView = (ImageView) itemView.findViewById(R.id.imageView);
        this.textView = (TextView) itemView.findViewById(R.id.textView);
        relativeLayout = (RelativeLayout)itemView.findViewById(R.id.relativeLayout);
    }
}

当单击案例 0 时，我需要杀死当前的 homefragment 并移动到另一个片段，但无法做到这一点，有人帮我实现这一目标

Answer 1

在这个解决方案中，我没有使用导航库

替换 MainActivity 上的片段。你应该在你的适配器类和主片段中创建接口：

public class MyListAdapter extends RecyclerView.Adapter<MyListAdapter.ViewHolder>{

  private OnItemClickListener onItemClickListener;

  //...

 @Override
 public void onBindViewHolder(ViewHolder holder, int position) {
   holder.bind(position, onItemClickListener);
 }

 //...


public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    public ImageView imageView;
    public TextView textView;
    public RelativeLayout relativeLayout;
    private OnItemClickListener listener;

    public ViewHolder(View itemView) {
        super(itemView);
        imageView = (ImageView) itemView.findViewById(R.id.imageView);
        textView = (TextView) itemView.findViewById(R.id.textView);
        relativeLayout = (RelativeLayout) itemView.findViewById(R.id.relativeLayout);
    }

    public void bind(int position, OnItemClickListener listener) {
        this.listener = listener;

        final MyListData myListData = listdata[position];
        textView.setText(listdata[position].getDescription());
        imageView.setImageResource(listdata[position].getImgId());
        relativeLayout.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        if (listener != null) {
            listener.onClick(getAdapterPosition());
        }
    }
}


  public void setOnItemClickListener(OnItemClickListener listener) {
      this.onItemClickListener = listener;
  }

  public interface OnItemClickListener{
      void onClick(int position);
  }

}

在HomeFragment:

public class HomeFragment extends Fragment implements 
MyListAdapter.OnItemClickListener {

  private OnItemClickListener onItemClickListener;

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

      //...

      adapter.setOnItemClickListener(this);

      //...
  }

  @Override
  public void onClick(int position) {
      if (onItemClickListener != null)
          onItemClickListener.onClick(position);
  }


  public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
      this.onItemClickListener = onItemClickListener;
  }

  public interface OnItemClickListener{
      void onClick(int position);
  }
}

在MainActivity:

public class MainActivity extends AppCompatActivity implements 
   HomeFragment.OnItemClickListener {

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

       //...

       HomeFragment homeFragment = new HomeFragment();
       homeFragment.setOnItemClickListener(this);

       getSupportFragmentManager().beginTransaction()
               .replace(R.id.your_frame_layout, homeFragment).commit();
   }

   //...

   @Override
   public void onClick(int position) {
       switch (position){
           case 0:
               //replace fragment
               break;

               //...
       }
   }
}