Question

我正在做recyclerview我有一个活动，我想在那个有recyclerview的活动中显示我的片段。我不知道我哪里出错了请帮我这个

这是我的活动 CategoryHairActivity.java

 import com.saloon.fragments.HairCategoryFragment;

    import android.os.Bundle;
    import android.support.v4.app.FragmentManager;
    import android.support.v4.app.FragmentTransaction;
    import android.support.v7.app.AppCompatActivity;
    import android.view.Menu;
    import android.view.MenuItem;

    public class CategoryHairActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_category_hair);
        HairCategoryFragment hairCategoryFragment=new HairCategoryFragment();
        if(hairCategoryFragment!=null){
            FragmentManager fmanager=getSupportFragmentManager();
            FragmentTransaction ft=fmanager.beginTransaction();
            ft.add(R.id.mainContent, hairCategoryFragment);
            ft.commit();
        }

    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
          return super.onOptionsItemSelected(item);
        }
    }

这是我的片段 HairCategoryFragment.java

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

     import com.saloon.adapters.HairCategoryAdapter;
      import com.saloon.callbacks.HairCategoryInformation;
      import com.saloon.myapp.R;

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

     public class HairCategoryFragment extends Fragment {

    public HairCategoryAdapter adapter;
    private RecyclerView recyclerView;
    @Override
    public View onCreateView(LayoutInflater inflater,
             ViewGroup container,  Bundle savedInstanceState) {
    View rootView=inflater.inflate(R.layout.hair_service_list_view, container,    false);
    adapter=new HairCategoryAdapter(getActivity(), getData());
    recyclerView=(RecyclerView) rootView.findViewById(R.id.serviceListView);
    recyclerView.setAdapter(adapter);
    recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
    return rootView;
    }
    private List<HairCategoryInformation> getData() {
        List<HairCategoryInformation> data = new   ArrayList<HairCategoryInformation>();
        String[] serviceNames ={"razor cut","lime cut","onion cut","step cut"};
        String[] servicePrices={"200","300","400","500"};

            for(int i=0;i<serviceNames.length && i<servicePrices.length;i++){
                HairCategoryInformation current = new HairCategoryInformation();
                current.serviceName=serviceNames[i];
                current.servicePrice=servicePrices[i];
                data.add(current);
            }
            return data;
    }
    }

Viewholder.java

 import com.saloon.myapp.R;

import android.support.v7.widget.RecyclerView.ViewHolder;
import android.view.View;
import android.widget.CheckBox;
import android.widget.TextView;

public class HairCategoryViewHolder extends ViewHolder{

public CheckBox checkbox;
public TextView name,price;

public HairCategoryViewHolder(View itemView) {
    super(itemView);
checkbox=(CheckBox) itemView.findViewById(R.id.serviceSelect);
name=(TextView) itemView.findViewById(R.id.serviceName);
price=(TextView) itemView.findViewById(R.id.servicePrice);
}

}

HairCategoryInformation.java

  public class HairCategoryInformation {
    public String serviceName,servicePrice;
     }

HairCategoryAdapter.java

import java.util.Collections;
 import java.util.List;

 import com.saloon.callbacks.HairCategoryInformation;
 import com.saloon.viewholder.HairCategoryViewHolder;

   import android.content.Context;
  import android.support.v7.widget.RecyclerView;
  import android.view.LayoutInflater;
  import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.ViewGroup;
 import android.widget.Toast;

  public class HairCategoryAdapter extends RecyclerView.Adapter<HairCategoryViewHolder>{

private LayoutInflater inflater;
private List<HairCategoryInformation> hairCategoryInformations = Collections.emptyList();
private Context context;
String text;
public HairCategoryAdapter(Context context,List<HairCategoryInformation> hairCategoryInformations) {
    this.context=context;
    inflater=LayoutInflater.from(context);
    this.hairCategoryInformations=hairCategoryInformations;
}

@Override
public HairCategoryViewHolder onCreateViewHolder(ViewGroup parent, int type) {
    View view=inflater.inflate(com.saloon.myapp.R.layout.hair_category_list, parent,false);
    HairCategoryViewHolder holder=new HairCategoryViewHolder(view);
    return holder;
}

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

@Override
public void onBindViewHolder(HairCategoryViewHolder holder, int position) {
HairCategoryInformation current=hairCategoryInformations.get(position);
holder.name.setText(current.serviceName);
holder.price.setText(current.servicePrice);
holder.checkbox.setTag(position);
holder.checkbox.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
Toast.makeText(context, v.getTag().toString(), Toast.LENGTH_SHORT).show();
    }
});
}
@Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
    super.onAttachedToRecyclerView(recyclerView);
}
}

Answer 1

为什么在初始化后检查hairCategoryFragment为null？无论如何，代码似乎很好，似乎你在布局上有问题。

RecyclerView没有显示任何内容

1 个答案: