如何从适配器类中的API响应中使用AlertDialogBox删除消息

Question

我正在处理消息传递应用程序。现在在对话活动中我想为发件人提供一个选项，可以删除他/她的消息。它的工作正常。问题是我想用alertDialogBox来做到这一点。当发件人长时间按他的信息，然后一个对话框将打开，他可以删除该特定的消息。当我使用改造我能做些什么来删除这种消息？

这里是我的自定义适配器类：

public class Single_chat_adapter extends RecyclerView.Adapter{ 

private static final int VIEW_TYPE_MESSAGE_SENT = 1; 
private static final int VIEW_TYPE_MESSAGE_RECEIVED = 2; 


private Context mContext; 
private List<Datum2> data; 
private String userID; 

private UserAuthenticationKey userAuthenticationKey; 
private SharedPreferences sharedPreferences; 
private SharedPreferences.Editor editor; 


public Single_chat_adapter(Context mContext, List<Datum2> data, String userID) { 
    this.mContext = mContext; 
    this.data = data; 
    this.userID = userID; 
} 

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


// Determines the appropriate ViewType according to the sender of the message. 
@Override 
public int getItemViewType(int position) { 
    Datum2 message = (Datum2) data.get(position); 

    if (message.getOriginatorId().equals(userID)) { 
     // If the current user is the sender of the message 
     return VIEW_TYPE_MESSAGE_SENT; 
    } else { 
     // If some other user sent the message 
     return VIEW_TYPE_MESSAGE_RECEIVED; 
    } 
} 
// Inflates the appropriate layout according to the ViewType. 
@Override 
public RecyclerView.ViewHolder onCreateViewHolder(final ViewGroup parent, int viewType) { 

    View view; 
    if (viewType == VIEW_TYPE_MESSAGE_SENT) { 
     view = LayoutInflater.from(parent.getContext()) 
       .inflate(R.layout.item_message_sent, parent, false); 
     return new SentMessageHolder(view); 

    } else if (viewType == VIEW_TYPE_MESSAGE_RECEIVED){ 
     view = LayoutInflater.from(parent.getContext()) 
       .inflate(R.layout.item_message_received, parent, false); 
     return new ReceivedMessageHolder(view); 
    } 
    return null; 
} 
// Passes the message object to a ViewHolder so that the contents can be bound to UI. 
@Override 
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { 
    Datum2 message = (Datum2) data.get(position); 

    switch (holder.getItemViewType()) { 
     case VIEW_TYPE_MESSAGE_SENT: 
      ((SentMessageHolder) holder).bind(message); 

      break; 
     case VIEW_TYPE_MESSAGE_RECEIVED: 
      ((ReceivedMessageHolder) holder).bind(message); 
    } 

    holder.itemView.setOnLongClickListener(new View.OnLongClickListener() { 
     @Override 
     public boolean onLongClick(final View view) { 

      return false; 
     } 
    }); 

} 

// Sent message view holder 
private class SentMessageHolder extends RecyclerView.ViewHolder { 
    TextView messageText, timeText; 
    ImageButton iB; 
    MsgDltAPIService msgDltAPIService; 
    String rec_id; 
    String content_id; 
    final int[] ids = new int[100]; 

    SentMessageHolder(final View itemView) { 
     super(itemView); 

     messageText = itemView.findViewById(R.id.text_message_body); 
     timeText = itemView.findViewById(R.id.text_message_time); 
     iB = itemView.findViewById(R.id.sentMessageTextDelete); 
     msgDltAPIService = RestClient.getClient().create(MsgDltAPIService.class); 

     iB.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       userAuthenticationKey = new UserAuthenticationKey(mContext.getApplicationContext()); 
       sharedPreferences = mContext.getApplicationContext().getSharedPreferences("user authentication", MODE_PRIVATE); 
       editor = sharedPreferences.edit(); 

       ids[0] = Integer.parseInt(content_id); 

       if (!TextUtils.isEmpty(content_id) && TextUtils.isDigitsOnly(content_id)) { 
        ids[0] = Integer.parseInt(content_id); 
       } else { 
        ids[0] = 0; 
       } 
       final MsgDltRequest msgDltRequest = new MsgDltRequest(
         ids, 
         rec_id); 
       Call<MsgDltResponse> call = 
         msgDltAPIService.msgDlt(userAuthenticationKey.getUserTokenKey(), 
           msgDltRequest); 
       call.enqueue(new Callback<MsgDltResponse>() { 
        @Override 
        public void onResponse(Call<MsgDltResponse> call, Response<MsgDltResponse> response) { 

         Toast.makeText(mContext.getApplicationContext(), "message deleted", 
           Toast.LENGTH_LONG).show(); 
        } 

        @Override 
        public void onFailure(Call<MsgDltResponse> call, Throwable t) { 
         Toast.makeText(mContext.getApplicationContext(), "please try again", 
           Toast.LENGTH_LONG).show(); 
        } 
       }); 
      } 
     }); 
    } 

    void bind(Datum2 message) { 
     messageText.setText(message.getMsg()); 

     // Format the stored timestamp into a readable String using method. 
     timeText.setText(message.getCreatedAt().getFormatTime()); 
     content_id = message.getContentId().toString(); 
     if (! message.getOriginatorId().equals(userID)){ 
      rec_id.valueOf(message.getOriginatorId()); 
     } 
     else { 
      rec_id = null; 
     } 
    } 

} 

// Received message view holder 
private class ReceivedMessageHolder extends RecyclerView.ViewHolder { 
    TextView messageText, timeText, nameText; 
    //  ImageView profileImage; 
    HexagonImageView profileImage; 

    ReceivedMessageHolder(View itemView) { 
     super(itemView); 

     messageText = itemView.findViewById(R.id.text_message_body); 
     timeText = itemView.findViewById(R.id.text_message_time); 
     nameText = itemView.findViewById(R.id.text_message_name); 
     profileImage = itemView.findViewById(R.id.image_message_profile); 
    } 

    void bind(Datum2 message) { 
     messageText.setText(message.getMsg()); 

     // Format the stored timestamp into a readable String using method. 
     timeText.setText(message.getCreatedAt().getFormatTime()); 
     nameText.setText(message.getOriginator().getFullName()); 

     // Insert the profile image from the URL into the ImageView. 
     Glide.with(mContext).load("myweburl" + data.get(getLayoutPosition()) 
       .getOriginator().getAvatar()).apply(RequestOptions.circleCropTransform()) 
       .into(profileImage); 
    } 
} 
} 

我设置了一个名为的iB按钮由我可以删除邮件。但不幸的是，我没有通过使用alertBox来做到这一点。

Answer 1

在您长时间按下的侦听器中，使用侦听器将消息对象传递给父活动/适配器，然后从父级打开一个对话框，将对象传递给它，现在删除数据时，只需从List<Datum2> data中删除消息，通知适配器

public class SingleChatAdapter extends RecyclerView.Adapter { 
// ... 
//... 
@Override 
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { 
    Datum2 message = (Datum2) data.get(position); 
    switch (holder.getItemViewType()) { 
    case VIEW_TYPE_MESSAGE_SENT: 
    ((SentMessageHolder) holder).bind(message); 
    break; 
    case VIEW_TYPE_MESSAGE_RECEIVED: 
    ((ReceivedMessageHolder) holder).bind(message); 
    } 
    holder.itemView.setOnLongClickListener(new View.OnLongClickListener() { 
    @Override 
    public boolean onLongClick(final View view) { 
    mListener.onMessageLongPressed(message); 
    return false; 
    } 
    }); 
    } 
    // .... 
    // ... 

// here is the listener interface parent need to implement 
public interface OnChildInteraction { 
    public void onMessageLongPressed(Datum2 message); 
} 
} 

父粗略实施将

public class ParentActicvity extends AppCompatActivity implements SingleChatAdapter.OnChildInteraction 
@override 
public void onMessageLongPressed(Datum2 message){ 
    // override delete button listener to call list.remove(message) 
    // notify adapter. 
// open dialog 

}