不能在課堂上解決符號findViewById與延伸RecyclerView.Adapter <RecyclerViewAdapter.ViewHolder>

Question

這個班裏

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

，我在方法@Override public void onBindViewHolder(ViewHolder Viewholder, int position) {

嘗試聲明foto = (ImageView) findViewById(R.id.Foto);，我試圖用protected void onCreate(Bundle savedInstanceState) {但它仍然是錯誤

適配器類

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

    Context context; 
    private static final String TAG = RecyclerViewAdapter.class.getSimpleName(); 

    List<GetDataAdapter> getDataAdapter; 

    ImageLoader imageLoader1; 
    private ImageView foto; 
    String getFoto; 
    String FIXURL = "http://192.168.0.103/AndroidFileUpload/"; 
    String url = FIXURL + "uploads/"; 


    public RecyclerViewAdapter(List<GetDataAdapter> getDataAdapter, Context context) { 

     super(); 
     this.getDataAdapter = getDataAdapter; 
     this.context = context; 
    } 

    @Override 
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 

     View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.recyclerview_items, parent, false); 

     ViewHolder viewHolder = new ViewHolder(v); 

     return viewHolder; 
    } 

    @Override 
    public void onBindViewHolder(ViewHolder Viewholder, int position) { 

     final GetDataAdapter getDataAdapter1 = getDataAdapter.get(position); 

     imageLoader1 = ServerImageParseAdapter.getInstance(context).getImageLoader(); 

//  imageLoader1.get(getDataAdapter1.getFoto(), 
//    ImageLoader.getImageListener(
//      Viewholder.networkImageView,//Server Image 
//      R.mipmap.ic_launcher,//Before loading server image the default showing image. 
//      android.R.drawable.ic_dialog_alert //Error image if requested image dose not found on server. 
//    ) 
//  ); 
//  getFoto = getDataAdapter1.getIdJalan();; 
//  String FullURL = url+getFoto; 
     foto = (ImageView) findViewById(R.id.Foto); 
//  Picasso.with(getApplicationContext()).load(url + getDataAdapter1.getFoto()).into(foto); 

     Viewholder.networkImageView.setImageUrl(getDataAdapter1.getFoto(), imageLoader1); 

     Viewholder.ImageTitleNameView.setText(getDataAdapter1.getIdJalan()); 

     Viewholder.itemView.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       Log.d(TAG, "coba nih5 : "+getDataAdapter1.getIdJalan()); 
// 
//    Intent intent = new Intent(v.getContext(), SeconActivity.class); 
//    intent.putExtra("key",getDataAdapter1.getImageTitleName());// getDataAdapter1 in your case 
//    context.startActivity(intent); 
      } 
     }); 

    } 

    @Override 
    public int getItemCount() { 

     return getDataAdapter.size(); 
    } 

    class ViewHolder extends RecyclerView.ViewHolder{ 

     public TextView ImageTitleNameView; 
     public NetworkImageView networkImageView; 

     public ViewHolder(View itemView) { 

      super(itemView); 

      ImageTitleNameView = (TextView) itemView.findViewById(R.id.textView_item); 

      networkImageView = (NetworkImageView) itemView.findViewById(R.id.VollyNetworkImageView1); 
     } 


    } 
} 

這是佈局

<?xml version="1.0" encoding="utf-8"?> 
<android.support.v7.widget.CardView 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:card_view="http://schemas.android.com/apk/res-auto" 
    android:id="@+id/cardview1" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    card_view:cardElevation="3dp" 
    card_view:contentPadding="3dp" 
    card_view:cardCornerRadius="3dp" 
    card_view:cardMaxElevation="3dp" 
    > 


    <RelativeLayout 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content"> 

     <de.hdodenhof.circleimageview.CircleImageView 
      android:id="@+id/Foto" 
      android:layout_width="100dp" 
      android:layout_height="100dp" 
      android:src="@mipmap/ic_launcher"/> 

     <TextView 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:textAppearance="?android:attr/textAppearanceLarge" 
      android:text="Image Name" 
      android:id="@+id/textView_item" 
      android:layout_centerVertical="true" 
      android:layout_toRightOf="@+id/VollyNetworkImageView1" 
      android:layout_toEndOf="@+id/VollyNetworkImageView1" 
      android:layout_marginLeft="20dp"/> 

    </RelativeLayout> 

    </android.support.v7.widget.CardView> 

Answer 1

這個錯誤意味着你使用了錯誤的對象調用findViewById()。您必須使用Activity或View來調用此方法。很可能您需要從傳遞給onBindViewHolder()方法的ViewHolder獲得視圖。像這樣的東西

View v = Viewholder.itemView; 
foto = (ImageView) v.findViewById(R.id.Foto); 

p.s.聲明ViewHolder Viewholder令人難以置信的混亂。通常變量名稱以小寫開頭。更好的是，使用一個明顯不同的詞，如ViewHolder holder。這就明確了什麼類型和名稱，而不需要仔細查看確切的字母和大小寫。