RecyclerAdapterのオブジェクトにgetItemを取得する際に問題が発生しました

Question

現在、PhotoクラスのRecyclerAdapterにgetItemという問題が発生しています。私は追加しようとしました

public int getItem(int pos){ 
    return getItem(pos); 
} 

しかし、それは動作していないようです。どのようにすればgetItem(position)にエラーがありますか？ （私が十分精緻化していない場合は、）

ここに私が間違っていることを教えてください。

ViewProfilePostsAdapter.java

public class ViewProfilePostsAdapter extends RecyclerView.Adapter<ViewProfilePostsAdapter.ViewHolder> { 
private static final String TAG = "CustomAdapter"; 

private String[] mDataSet; 
private int[] getItemIn; 

private LayoutInflater mInflater; 
private int mLayoutResource; 
private Context mContext; 
private DatabaseReference mReference; 
private String currentUsername; 

private Photo mPic; 



public static class ViewHolder extends RecyclerView.ViewHolder { 
    //private final TextView textView; 

    ImageView mProfileImage; 
    String likesString; 
    TextView username, timeDelta, caption, likes, liked; 
    ImageView postImage; 
    ImageView heartRed, heartWhite; 

    UserAccountSettings settings = new UserAccountSettings(); 
    User user = new User(); 
    StringBuilder users; 
    String mLikesString; 
    boolean likeByCurrentUser; 
    Heart heart; 
    GestureDetector detector; 
    Photo photo; 

    public ViewHolder(View convertView) { 
     super(convertView); 

     if(convertView == null) { 
      username = (TextView) convertView.findViewById(R.id.display_name); 
      postImage = (ImageView) convertView.findViewById(R.id.post_image); 
      caption = (TextView) convertView.findViewById(R.id.image_caption); 
      timeDelta = (TextView) convertView.findViewById(R.id.image_time_posted); 
      likes = (TextView) convertView.findViewById(R.id.tvLikesString); 
      mProfileImage = (ImageView) convertView.findViewById(R.id.f_profile_image); 
      heartRed = (ImageView) convertView.findViewById(R.id.image_heart_red); 
      heartWhite = (ImageView) convertView.findViewById(R.id.image_heart_white); 
      heart = new Heart(heartWhite, heartRed); 
      liked = (TextView) convertView.findViewById(R.id.likeText); 
     } 
    } 

} 

public ViewProfilePostsAdapter(String[] dataSet, int[] intSet) { 
    mDataSet = dataSet; 
    getItemIn = intSet; 
} 

@Override 
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) { 
    View v = LayoutInflater.from(viewGroup.getContext()) 
      .inflate(R.layout.layout_post_listitem, viewGroup, false); 

    return new ViewHolder(v); 
} 

@Override 
public void onBindViewHolder(final ViewHolder viewHolder, final int position) 
{ 
    Log.d(TAG, "Element " + position + " set."); 

    viewHolder.photo = getItem(position); 
    viewHolder.detector = new GestureDetector(mContext, new GestureListener(viewHolder)); 

    getCurrentUsername(); 

    getLikesString(viewHolder); 

    viewHolder.caption.setText(getItem(position).getCaption()); 

    String timestampDifference = getTimestampDifference(getItem(position)); 
    if(!timestampDifference.equals("0")){ 
     viewHolder.timeDelta.setText(timestampDifference + " DAYS AGO"); 
    }else{ 
     viewHolder.timeDelta.setText("TODAY"); 
    } 

    final ImageLoader imageLoader = ImageLoader.getInstance(); 
    imageLoader.displayImage(getItem(position).getImage_path(), viewHolder.postImage); 


    //get the profile image and username 
    DatabaseReference reference = FirebaseDatabase.getInstance().getReference(); 
    Query query = reference 
      .child(mContext.getString(R.string.dbname_user_account_settings)) 
      .orderByChild(mContext.getString(R.string.field_user_id)) 
      .equalTo(getItem(position).getUser_id()); 
    query.addListenerForSingleValueEvent(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      Log.e(TAG, "onDataChange: OnDataChange ******************************************************************************"); 
      for(DataSnapshot singleSnapshot : dataSnapshot.getChildren()){ 


       Log.e(TAG, "onDataChange: found user: " 
         + singleSnapshot.getValue(UserAccountSettings.class).getUsername() + "****************************"); 

       holder.username.setText(singleSnapshot.getValue(UserAccountSettings.class).getUsername()); 


       imageLoader.displayImage(singleSnapshot.getValue(UserAccountSettings.class).getProfile_photo(), 
         holder.mProfileImage); 

       holder.settings = singleSnapshot.getValue(UserAccountSettings.class); 

      } 

     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

     } 
    }); 

    Query userQuery = mReference 
      .child(mContext.getString(R.string.dbname_users)) 
      .orderByChild(mContext.getString(R.string.field_user_id)) 
      .equalTo(getItem(position).getUser_id()); 
    userQuery.addListenerForSingleValueEvent(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      for(DataSnapshot singleSnapshot : dataSnapshot.getChildren()){ 
       Log.d(TAG, "onDataChange: found user: " + 
         singleSnapshot.getValue(User.class).getUsername()); 

       viewHolder.user = singleSnapshot.getValue(User.class); 
      } 

     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

     } 
    }); 

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

public int getItem(int pos){ 
    return getItem(pos); 
} 



public class GestureListener extends GestureDetector.SimpleOnGestureListener{ 

    ViewHolder mHolder; 
    public GestureListener(ViewHolder holder) { 
     mHolder = holder; 
    } 

    @Override 
    public boolean onDown(MotionEvent e) { 
     return true; 
    } 

    @Override 
    public boolean onDoubleTap(MotionEvent e) { 
     Log.d(TAG, "onDoubleTap: double tap detected."); 

     DatabaseReference reference = FirebaseDatabase.getInstance().getReference(); 
     Query query = reference 
       .child(mContext.getString(R.string.dbname_photos)) 
       .child(mHolder.photo.getPhoto_id()) 
       .child(mContext.getString(R.string.field_likes)); 
     query.addListenerForSingleValueEvent(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       for(DataSnapshot singleSnapshot : dataSnapshot.getChildren()) 
{ 

        String keyID = singleSnapshot.getKey(); 

        //case1: Then user already liked the photo 
        if(mHolder.likeByCurrentUser && 
          singleSnapshot.getValue(Like.class).getUser_id() 
            .equals(FirebaseAuth.getInstance().getCurrentUser().getUid())){ 

         mReference.child(mContext.getString(R.string.dbname_photos)) 
           .child(mHolder.photo.getPhoto_id()) 
           .child(mContext.getString(R.string.field_likes)) 
           .child(keyID) 
           .removeValue(); 
        mReference.child(mContext.getString(R.string.dbname_user_photos)) 
           .child(mHolder.photo.getUser_id()) 
           .child(mHolder.photo.getPhoto_id()) 
           .child(mContext.getString(R.string.field_likes)) 
           .child(keyID) 
           .removeValue(); 

         mHolder.heart.toggleLike(); 
         getLikesString(mHolder); 
        } 
        //case2: The user has not liked the photo 
        else if(!mHolder.likeByCurrentUser){ 
         //add new like 
         addNewLike(mHolder); 
         break; 
        } 
       } 
       if(!dataSnapshot.exists()){ 
        //add new like 
        addNewLike(mHolder); 
       } 
      } 

      @Override 
      public void onCancelled(DatabaseError databaseError) { 

      } 
     }); 

     return true; 
    } 
} 

private void addNewLike(final ViewHolder holder){ 
    Log.d(TAG, "addNewLike: adding new like"); 

    String newLikeID = mReference.push().getKey(); 
    Like like = new Like(); 
    like.setUser_id(FirebaseAuth.getInstance().getCurrentUser().getUid()); 

    mReference.child(mContext.getString(R.string.dbname_photos)) 
      .child(holder.photo.getPhoto_id()) 
      .child(mContext.getString(R.string.field_likes)) 
      .child(newLikeID) 
      .setValue(like); 

    mReference.child(mContext.getString(R.string.dbname_user_photos)) 
      .child(holder.photo.getUser_id()) 
      .child(holder.photo.getPhoto_id()) 
      .child(mContext.getString(R.string.field_likes)) 
      .child(newLikeID) 
      .setValue(like); 

    holder.heart.toggleLike(); 
    getLikesString(holder); 
} 

private void getCurrentUsername(){ 
    Log.d(TAG, "getCurrentUsername: retrieving user account settings"); 
    DatabaseReference reference = FirebaseDatabase.getInstance().getReference(); 
    Query query = reference 
      .child(mContext.getString(R.string.dbname_users)) 
      .orderByChild(mContext.getString(R.string.field_user_id)) 
      .equalTo(FirebaseAuth.getInstance().getCurrentUser().getUid()); 
    query.addListenerForSingleValueEvent(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      for(DataSnapshot singleSnapshot : dataSnapshot.getChildren()){ 
       currentUsername = singleSnapshot.getValue(UserAccountSettings.class).getUsername(); 
      } 

     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

     } 
    }); 
} 

private void getLikesString(final ViewHolder holder){ 
    Log.d(TAG, "getLikesString: getting likes string"); 

    try{ 
     DatabaseReference reference = FirebaseDatabase.getInstance().getReference(); 
     Query query = reference 
       .child(mContext.getString(R.string.dbname_photos)) 
       .child(holder.photo.getPhoto_id()) 
       .child(mContext.getString(R.string.field_likes)); 
     query.addListenerForSingleValueEvent(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       holder.users = new StringBuilder(); 
       for(DataSnapshot singleSnapshot : dataSnapshot.getChildren()) 
{ 

        DatabaseReference reference = FirebaseDatabase.getInstance().getReference(); 
        Query query = reference 
          .child(mContext.getString(R.string.dbname_users)) 
          .orderByChild(mContext.getString(R.string.field_user_id)) 
          .equalTo(singleSnapshot.getValue(Like.class).getUser_id()); 
        query.addListenerForSingleValueEvent(new ValueEventListener() { 
         @Override 
         public void onDataChange(DataSnapshot dataSnapshot) { 
          for(DataSnapshot singleSnapshot : dataSnapshot.getChildren()){ 
           Log.d(TAG, "onDataChange: found like: " + 
             singleSnapshot.getValue(User.class).getUsername()); 

           holder.users.append(singleSnapshot.getValue(User.class).getUsername()); 
           holder.users.append(","); 
          } 

          String[] splitUsers = holder.users.toString().split(","); 

          if(holder.users.toString().contains(currentUsername + ",")){ 
           holder.likeByCurrentUser = true; 
          }else{ 
           holder.likeByCurrentUser = false; 
          } 

          int length = splitUsers.length; 
          if(length == 1){ 
           holder.likesString = "Liked by " + splitUsers[0]; 
          } 
          else if(length == 2){ 
           holder.likesString = "Liked by " + splitUsers[0] 
             + " and " + splitUsers[1]; 
          } 
          else if(length == 3){ 
           holder.likesString = "Liked by " + splitUsers[0] 
             + ", " + splitUsers[1] 
             + " and " + splitUsers[2]; 

          } 
          else if(length == 4){ 
           holder.likesString = "Liked by " + splitUsers[0] 
             + ", " + splitUsers[1] 
             + ", " + splitUsers[2] 
             + " and " + splitUsers[3]; 
          } 
          else if(length > 4){ 
           holder.likesString = "Liked by " + splitUsers[0] 
             + ", " + splitUsers[1] 
             + ", " + splitUsers[2] 
             + " and " + (splitUsers.length - 3) + " others"; 
          } 
          Log.d(TAG, "onDataChange: likes string: " + holder.likesString); 
          //setup likes string 
          setupLikesString(holder, holder.likesString); 
         } 

         @Override 
         public void onCancelled(DatabaseError databaseError) 
{ 

         } 
        }); 
       } 
       if(!dataSnapshot.exists()){ 
        holder.likesString = ""; 
        holder.likeByCurrentUser = false; 
        //setup likes string 
        setupLikesString(holder, holder.likesString); 
       } 
      } 

      @Override 
      public void onCancelled(DatabaseError databaseError) { 

      } 
     }); 
    }catch (NullPointerException e){ 
     Log.e(TAG, "getLikesString: NullPointerException: " + e.getMessage() 
); 
     holder.likesString = ""; 
     holder.likeByCurrentUser = false; 
     //setup likes string 
     setupLikesString(holder, holder.likesString); 
    } 
} 

private void setupLikesString(final ViewHolder holder, String likesString) { 
    Log.d(TAG, "setupLikesString: likes string:" + holder.likesString); 

    if (holder.likeByCurrentUser) { 
     Log.d(TAG, "setupLikesString: photo is liked by current user"); 
     holder.liked.setText("UnLike"); 
     holder.heartWhite.setVisibility(View.GONE); 
     holder.heartRed.setVisibility(View.VISIBLE); 
     holder.heartRed.setOnTouchListener(new View.OnTouchListener() { 
      @Override 
      public boolean onTouch(View v, MotionEvent event) { 
       return holder.detector.onTouchEvent(event); 
      } 
     }); 
    } else { 
     Log.d(TAG, "setupLikesString: photo is not liked by current user"); 
     holder.liked.setText("Like"); 
     holder.heartWhite.setVisibility(View.VISIBLE); 
     holder.heartRed.setVisibility(View.GONE); 
     holder.heartWhite.setOnTouchListener(new View.OnTouchListener() { 
      @Override 
      public boolean onTouch(View v, MotionEvent event) { 
       return holder.detector.onTouchEvent(event); 
      } 
     }); 
    } 
    holder.likes.setText(likesString); 

} 


//---------------------------------------------end of likes---------------------------- 

private String getTimestampDifference(Photo photo){ 
    Log.d(TAG, "getTimestampDifference: getting timestamp difference."); 

    String difference = ""; 
    Calendar c = Calendar.getInstance(); 
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.CANADA); 
    sdf.setTimeZone(TimeZone.getTimeZone("Canada/Pacific"));//google 'android list of timezones' 
    Date today = c.getTime(); 
    sdf.format(today); 
    Date timestamp; 
    final String photoTimestamp = photo.getDate_created(); 
    try{ 
     timestamp = sdf.parse(photoTimestamp); 
     difference = String.valueOf(Math.round(((today.getTime() - timestamp.getTime())/1000/60/60/24))); 
    }catch (ParseException e){ 
     Log.e(TAG, "getTimestampDifference: ParseException: " + e.getMessage()); 
     difference = "0"; 
    } 
    return difference; 
} 
} 

Photo.java

public class Photo implements Parcelable { 

private String caption; 
private String date_created; 
private String photo_id; 
private String user_id; 
private String tags; 
private String image_path; 
private List<Like> likes; 


public Photo(){ 

} 

public Photo(String caption, String date_created, String photo_id, String user_id, String tags, String image_path, List<Like> likes) { 
    this.caption = caption; 
    this.date_created = date_created; 
    this.photo_id = photo_id; 
    this.user_id = user_id; 
    this.tags = tags; 
    this.image_path = image_path; 
    this.likes = likes; 
} 

protected Photo(Parcel in) { 
    caption = in.readString(); 
    date_created = in.readString(); 
    photo_id = in.readString(); 
    user_id = in.readString(); 
    tags = in.readString(); 
    image_path = in.readString(); 
} 

public static final Creator<Photo> CREATOR = new Creator<Photo>() { 
    @Override 
    public Photo createFromParcel(Parcel in) { 
     return new Photo(in); 
    } 

    @Override 
    public Photo[] newArray(int size) { 
     return new Photo[size]; 
    } 
}; 

public String getCaption() { 
    return caption; 
} 

public void setCaption(String caption) { 
    this.caption = caption; 
} 

public String getDate_created() { 
    return date_created; 
} 

public void setDate_created(String date_created) { 
    this.date_created = date_created; 
} 

public String getPhoto_id() { 
    return photo_id; 
} 

public void setPhoto_id(String photo_id) { 
    this.photo_id = photo_id; 
} 

public String getUser_id() { 
    return user_id; 
} 

public void setUser_id(String user_id) { 
    this.user_id = user_id; 
} 

public String getTags() { 
    return tags; 
} 

public void setTags(String tags) { 
    this.tags = tags; 
} 

public String getImage_path() { 
    return image_path; 
} 

public void setImage_path(String image_path) { 
    this.image_path = image_path; 
} 

public List<Like> getLikes() { 
    return likes; 
} 

public void setLikes(List<Like> likes) { 
    this.likes = likes; 
} 

@Override 
public String toString() { 
    return "Photo{" + 
      "caption='" + caption + '\'' + 
      ", date_created='" + date_created + '\'' + 
      ", photo_id='" + photo_id + '\'' + 
      ", user_id='" + user_id + '\'' + 
      ", tags='" + tags + '\'' + 
      ", image_path='" + image_path + '\'' + 
      ", likes=" + likes + 
      '}'; 
} 

@Override 
public int describeContents() { 
    return 0; 
} 

@Override 
public void writeToParcel(Parcel parcel, int i) { 
    parcel.writeString(caption); 
    parcel.writeString(date_created); 
    parcel.writeString(photo_id); 
    parcel.writeString(user_id); 
    parcel.writeString(tags); 
    parcel.writeString(image_path); 
} 
} 

Answer 1

あなたの関数が自分自身を呼び出します。

public int getItem(int pos){ 
    return getItem(pos); 
} 

あなたはいくつかのことを行う必要があり、問題を解決するには： 1）アダプタには写真オブジェクトのコレクションが必要です。例えば。 ArrayListリスト。

これは、多分Countorから入力する必要があります。したがって、アダプタにはこのリストを含むコンストラクタが必要です。

2）これまでの変更のgetItem方法：すべての

public Photo getItem(int pos){ 
    return list.get(pos); 
} 

Answer 2

まず、あなたのgetItem機能は、（私が推測する）オブジェクトを返す必要があります。 また正直なところ、私は達成しようとしていることを少し混乱させています。あなたはリサイクル業者のビューの特定の位置にアイテムを手に入れたいと思っていましたか？あなたのViewholderクラスで

がちょうどRecyclerViewAdapterであなたのOnBindViewHolder関数のコード

int position = 0; 

の下に追加し、あなたのrecyclerviewの各項目の位置があり

public void onBindViewHolder(RecyclerViewAdapter.MyViewHolder holder, int position) { 

    Model yourModel= modelList.get(position); 


    holder.position = position; 



} 

あなたのrecyclerviewでOnClickListenerを取得しようとしているのであれば。以下の方法が役に立つかもしれません。インタフェース

public interface RecyclerViewOnItemClickListener { 

void OnItemClickListener(View view, int position); 
void OnItemLongClickListener(View view, int position); 

}

を作成します。このコードは、あなたがrecyclerviewを表示したい自分のメインの活動やあなたのフラグメントでRecyclerAdapterクラス

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

最終段階に入ります

recyclerViewAdapter.setOnItemClickListener(new RecyclerViewOnItemClickListener() { 
     @Override 
     public void OnItemClickListener(View view, int position) { 
      Model yourModel= modelList.get(position); 

     } 

     @Override 
     public void OnItemLongClickListener(View view, int position) { 

     } 
    }); 

ここでは、アイテムを特定の位置に取得する方法を示します。 希望する;）