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android recyclerviewはアイテムを表示しません

Recyclerview内にこれらのアイテムを表示したいのですが、まったく表示されず、エラーが表示されません。たぶんあなたたちは私を助けることができます。

MainActivity.Java

    RecyclerView recyclerView = (RecyclerView)findViewById(R.id.rec);
List<MenuData> list = new ArrayList<>();
        recyclerView.setHasFixedSize(true);
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(linearLayoutManager);

        MenuRecAdapter menuRecAdapter = new MenuRecAdapter(list);
        recyclerView.setAdapter(menuRecAdapter);

RecyclerViewアダプター：

    public class MenuRecAdapter extends RecyclerView.Adapter<RecViewHolder>{

    private List<MenuData> mList;
    Activity context;

    public MenuRecAdapter(List<MenuData> mList){
        this.mList = mList;
    }

    public int getItemCount(){
        return mList.size();
    }

    public RecViewHolder onCreateViewHolder(ViewGroup viewGroup, int position){

        View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.menuitem, viewGroup, false);
        RecViewHolder pvh = new RecViewHolder(v);
        return pvh;
    }

    public void onBindViewHolder(RecViewHolder holder, int i){
        holder.menuTeXT.setText(mList.get(i).text);
    }

    @Override
    public void onAttachedToRecyclerView(RecyclerView recyclerView) {
        super.onAttachedToRecyclerView(recyclerView);
    }

}

アイテムのViewHolder：

  public class RecViewHolder extends RecyclerView.ViewHolder {

    public TextView menuTeXT;

    public RecViewHolder(View itemView){
        super(itemView);

        menuTeXT = (TextView)itemView.findViewById(R.id.menuTXT);
    }
}

そして、recyclerviewに入れたいデータ（表示されないもの）：

    class MenuData {

    String text;

    MenuData(String text){
        this.text = text;
    }

    private List<MenuData> list;

    private void initializeData(){
        list = new ArrayList<>();
        list.add(new MenuData("Featured"));
        list.add(new MenuData("Categories"));
        list.add(new MenuData("Sell"));
        list.add(new MenuData("Settings"));
        list.add(new MenuData("Logout"));
    }

}

前もって感謝します

javaandroidandroid-recyclerview
23
svenvdz

MainActivityで

ArrayList<String> list = new ArrayList<>();
list.add("something1");
list.add("something2");

RecyclerView recyclerView = (RecyclerView)findViewById(R.id.rec);
recyclerView.setHasFixedSize(true);

LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView.setLayoutManager(linearLayoutManager);

MenuRecAdapter menuRecAdapter = new MenuRecAdapter(list);
recyclerView.setAdapter(menuRecAdapter);

RecyclerViewアダプター

public class MenuRecAdapter extends RecyclerView.Adapter<RecViewHolder>{

private ArrayList<String> mList = new ArrayList<>();
Activity context;

public MenuRecAdapter(ArrayList<String> mList){
    this.mList = mList;
}

public int getItemCount(){
    return mList.size();
}

public RecViewHolder onCreateViewHolder(ViewGroup viewGroup, int position){

    View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.menuitem, viewGroup, false);
    RecViewHolder pvh = new RecViewHolder(v);
    return pvh;
}

public void onBindViewHolder(RecViewHolder holder, int i){
    holder.menuTeXT.setText(mList.get(i));
}

@Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
    super.onAttachedToRecyclerView(recyclerView);
}
}

そして、ViewHolderは同じままです...

public class RecViewHolder extends RecyclerView.ViewHolder {

public TextView menuTeXT;

public RecViewHolder(View itemView){
    super(itemView);

    menuTeXT = (TextView)itemView.findViewById(R.id.menuTXT);
}
}

menuDataクラスも削除します。上記のコードは正常に動作するはずです。

52
Kushal Sharma

データを取得していないので、リストをアダプタに渡すときに問題が発生すると思います。リストのコピーを作成していないので、リストの参照を直接アダプターに渡しているようです。 MenuRecAdapter menuRecAdapter = new MenuRecAdapter(new Arraylist(list));を試すことをお勧めします

0
yongsunCN