Wie aktualisiert man Artikel in RecycleView?

Question

Ich erstelle Anwendung, in der ich Funktionen wie Facebook Timeline geben, wo Menschen ihre Geschichte aktualisieren können und jeder Benutzer die Geschichte mögen oder kommentieren kann. Alles funktioniert gut, aber das Problem ist, dass bei einer Aktualisierung der Story die Daten der aktualisierten Story auf dem Server gespeichert, aber nicht gleichzeitig in der Recycle-Ansicht hinzugefügt werden. Wenn der Benutzer zurückgeht und erneut auf dem Zeitleistenbildschirm erscheint, wird die Liste aktualisiert. Wie kann ich dieses Problem lösen?

Individuelle Adapter

public class TimeLineListAdapter extends RecyclerView.Adapter<TimeLineListAdapter.ViewHolder> { 
    private List<TimeLineItem> timeLineItems; 
    String message, storyId, token; 
    private Context context; 
    ImageLoader imageLoader = AppController.getInstance().getImageLoader(); 

    public TimeLineListAdapter(List<TimeLineItem> timeLineItems, Context context) { 
     super(); 
     this.context = context; 
     this.timeLineItems = timeLineItems; 
    } 

    @Override 
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 
     View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.timeline_item, parent, false); 
     ViewHolder viewHolder = new ViewHolder(v); 
     return viewHolder; 
    } 

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

     //Getting the particular item from the list 
     TimeLineItem item = timeLineItems.get(position); 

     if (item.getTotalLikes().equals("0")){ 
      holder.txtLike.setText(""); 
     }else { 
      holder.txtLike.setText(item.getTotalLikes()); 
     } 

     if (item.getTotalComment().equals("0")){ 
      holder.txtComment.setText(""); 
     }else { 
      holder.txtComment.setText("("+item.getTotalComment()+")"); 
     } 

     if (item.getIsLike() == 0){ 

     }else { 
      holder.imageLike.setImageBitmap(null); 
      holder.imageLike.setBackgroundResource(R.drawable.islike); 
      holder.txtLike.setTextColor(Color.parseColor("#3498db")); 
     } 

     holder.name.setText(item.getName() + " " + item.getLname()); 


     /*Long.parseLong(item.getTimeStamp()), 
       System.currentTimeMillis(), DateUtils.SECOND_IN_MILLIS);*/ 
     holder.timestamp.setText(item.getTimeStamp()); 

     // Chcek for empty status message 
     if (!TextUtils.isEmpty(item.getStatus())) { 
      holder.statusMsg.setText(item.getStatus()); 
      holder.statusMsg.setVisibility(View.VISIBLE); 
     } else { 
      // status is empty, remove from view 
      holder.statusMsg.setVisibility(View.GONE); 
     } 

     // Checking for null feed url 
     if (item.getUrl() != null) { 
      holder.url.setText(Html.fromHtml("<a href=\"" + item.getUrl() + "\">" 
        + item.getUrl() + "</a> ")); 

      // Making url clickable 
      holder.url.setMovementMethod(LinkMovementMethod.getInstance()); 
      holder.url.setVisibility(View.VISIBLE); 
     } else { 
      // url is null, remove from the view 
      holder.url.setVisibility(View.GONE); 
     } 

     // user profile pic 
     holder.profilePic.setImageUrl(item.getProfilePic(), imageLoader); 

     // Feed image 
     if (item.getImge() != null) { 
      holder.feedImageView.setImageUrl(item.getImge(), imageLoader); 
      holder.feedImageView.setVisibility(View.VISIBLE); 
      holder.feedImageView 
        .setResponseObserver(new TimeLineImageView.ResponseObserver() { 
         @Override 
         public void onError() { 
         } 

         @Override 
         public void onSuccess() { 
         } 
        }); 
     } else { 
      holder.feedImageView.setVisibility(View.GONE); 
     } 

     holder.txtComment.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 

       final TimeLineItem m = timeLineItems.get(position); 
       String ide = String.valueOf(m.getId()); 

       Intent intent = new Intent(context, StoryDetailActivity.class); 
       intent.putExtra("storyId",ide); 
       context.startActivity(intent); 
      } 
     }); 

     holder.txtCommentLabel.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       final TimeLineItem m = timeLineItems.get(position); 
       String ide = String.valueOf(m.getId()); 

       Intent intent = new Intent(context, StoryDetailActivity.class); 
       intent.putExtra("storyId",ide); 
       context.startActivity(intent); 
      } 
     }); 


     holder.imageLike.setOnTouchListener(new View.OnTouchListener() { 
      @Override 
      public boolean onTouch(View view, MotionEvent motionEvent) { 

       TimelineActivity t = new TimelineActivity(); 

       final TimeLineItem m = timeLineItems.get(position); 
       String ide = String.valueOf(m.getId()); 

       likeStory(ide,t.token); 

       return false; 
      } 
     }); 

    } 

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

    class ViewHolder extends RecyclerView.ViewHolder{ 

     TextView name, timestamp, statusMsg, url, txtLike, txtComment, txtCommentLabel; 
     NetworkImageView profilePic; 
     TimeLineImageView feedImageView; 
     ImageView imageLike; 

     //Initializing Views 
     public ViewHolder(View itemView) { 
      super(itemView); 
      name = (TextView) itemView.findViewById(R.id.name); 
      timestamp = (TextView) itemView.findViewById(R.id.timestamp); 
      statusMsg = (TextView) itemView.findViewById(R.id.txtStatusMsg); 
      url = (TextView) itemView.findViewById(R.id.txtUrl); 
      profilePic = (NetworkImageView) itemView.findViewById(R.id.profilePic); 
      feedImageView = (TimeLineImageView) itemView.findViewById(R.id.feedImage1); 
      imageLike = (ImageView) itemView.findViewById(R.id.imgLike); 
      txtLike = (TextView) itemView.findViewById(R.id.txtLike); 
      txtComment = (TextView) itemView.findViewById(R.id.txtComment); 
      txtCommentLabel = (TextView) itemView.findViewById(R.id.txtCommentLabel); 
     } 
    } 

    private void likeStory(final String story_id, final String token) { 
     // Tag used to cancel the request 
     String tag_string_req = "req_register"; 

     StringRequest strReq = new StringRequest(Request.Method.POST, AppConfig.likeStory, new Response.Listener<String>() { 

      @Override 
      public void onResponse(String response) { 

       try { 
        JSONObject jObj = new JSONObject(response); 
        boolean error = jObj.getBoolean("status"); 
        message = jObj.getString("message"); 
        if (error) { 

        } else { 

        } 
       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 

      } 
     }, new Response.ErrorListener() { 

      @Override 
      public void onErrorResponse(VolleyError error) { 
       Toast.makeText(context, "Oops something went wrong...", Toast.LENGTH_LONG).show(); 
      } 
     }) { 

      @Override 
      protected Map<String 
        , String> getParams() { 
       // Posting params to register url 
       Map<String, String> params = new HashMap<String, String>(); 
       params.put("my_token", token); 
       params.put("story_id", story_id); 

       return params; 
      } 

     }; 

     // Adding request to request queue 
     AppController.getInstance().addToRequestQueue(strReq, tag_string_req); 
    } 

} 

TimeLineActivity

public void getTimeLineData(final String token, final String page) { 


     String tag_string_req = "req_register"; 
     // making fresh volley request and getting json 
     StringRequest strReq = new StringRequest(Request.Method.POST, AppConfig.timeline, new Response.Listener<String>() { 

      @Override 
      public void onResponse(String response) { 
       VolleyLog.d(TAG, "Response: " + response.toString()); 
       if (response != null) { 
        try { 
         JSONObject jObj = new JSONObject(response); 
         boolean error = jObj.getBoolean("status"); 
         String message = jObj.getString("message"); 
         if (error) { 
          totalPages = jObj.getInt("totalPages"); 
          pageCount = jObj.getInt("page"); 

          int limit = jObj.getInt("limit"); 
          parseJsonFeed(response); 
         } 

        } catch (Exception e) { 

        } 

       } 
      } 
     }, new Response.ErrorListener() { 

      @Override 
      public void onErrorResponse(VolleyError error) { 
       VolleyLog.d(TAG, "Error: " + error.getMessage()); 
      } 
     }) { 

      @Override 
      protected Map<String, String> getParams() { 
       // Posting params to register url 
       Map<String, String> params = new HashMap<String, String>(); 
       params.put("my_token", token); 
       params.put("page", page); 
       params.put("limit", "5"); 

       return params; 
      } 
     }; 

     // Adding request to request queue 
     AppController.getInstance().addToRequestQueue(strReq, tag_string_req); 

    } 

    private void parseJsonFeed(String response) { 
     try { 
      JSONObject jsonObj = new JSONObject(response); 
      JSONArray feedArray = jsonObj.getJSONArray("data"); 

      for (int i = 0; i < feedArray.length(); i++) { 
       JSONObject feedObj = (JSONObject) feedArray.get(i); 

       TimeLineItem item = new TimeLineItem(); 
       item.setId(feedObj.getInt("id")); 
       item.setName(feedObj.getString("name")); 
       item.setLname(feedObj.getString("lname")); 

       // Image might be null sometimes 
       String image = feedObj.isNull("image") ? null : feedObj 
         .getString("image"); 

       if (image.equals("")) { 
        item.setImge(image); 
       } else { 
        item.setImge(AppConfig.storyPic + image); 
       } 

       item.setStatus(feedObj.getString("story_text")); 
       item.setProfilePic(AppConfig.profilePic + feedObj.getString("profile_pic")); 
       item.setTimeStamp(feedObj.getString("time_stamp")); 
       item.setIsLike(feedObj.getInt("is_like")); 
       item.setTotalLikes(feedObj.getString("total_likes")); 
       item.setTotalComment(feedObj.getString("total_comments")); 

       /*// url might be null sometimes 
       String feedUrl = feedObj.isNull("url") ? null : feedObj 
         .getString("url"); 
       item.setUrl(feedUrl);*/ 

       timeLineItems.add(item); 
      } 

      // notify data changes to list adapater 
      adapter.notifyDataSetChanged(); 


     } catch (JSONException e) { 
      e.printStackTrace(); 
     } 
    } 

private void addStory(final String story_text, final String token, final String image) { 
     // Tag used to cancel the request 
     String tag_string_req = "req_register"; 

     pDialog.setMessage("Please wait ..."); 
     showDialog(); 

     StringRequest strReq = new StringRequest(Request.Method.POST, AppConfig.addStory, new Response.Listener<String>() { 

      @Override 
      public void onResponse(String response) { 
       hideDialog(); 

       try { 
        JSONObject jObj = new JSONObject(response); 
        boolean error = jObj.getBoolean("status"); 
        message = jObj.getString("message"); 
        if (error) { 
         adapter.notifyDataSetChanged(); 
         txtStatusBox.setText(""); 
         imgImageUpload.setImageBitmap(null); 
         imgImageUpload.setBackgroundResource(R.drawable.image); 
         Toast.makeText(TimelineActivity.this, message, Toast.LENGTH_SHORT).show(); 
         slidingUpPanelLayout.setPanelState(SlidingUpPanelLayout.PanelState.COLLAPSED); 

        } else { 

         // Error occurred in registration. Get the error 
         // message 
         String errorMsg = jObj.getString("message"); 
         Toast.makeText(TimelineActivity.this, errorMsg, Toast.LENGTH_LONG).show(); 
        } 
       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 

      } 
     }, new Response.ErrorListener() { 

      @Override 
      public void onErrorResponse(VolleyError error) { 
       Toast.makeText(TimelineActivity.this, "Oops something went wrong...", Toast.LENGTH_LONG).show(); 
       hideDialog(); 
      } 
     }) { 

      @Override 
      protected Map<String 
        , String> getParams() { 
       // Posting params to register url 
       Map<String, String> params = new HashMap<String, String>(); 
       params.put("my_token", token); 
       params.put("story_text", story_text); 
       params.put("image", image); 

       return params; 
      } 

     }; 

     // Adding request to request queue 
     AppController.getInstance().addToRequestQueue(strReq, tag_string_req); 
    } 

Answer 1

Sie müssen irgendeine Art von Polling-Mechanismus auf Serverseite implementieren, dies zu tun. Es gibt einen Workaround dafür, aber es gilt nicht als gute Übung. Sie können eine Timer verwenden, um Ihre getTimeline-Funktion regelmäßig aufzurufen, um die Recycler-Ansicht zu aktualisieren. So etwas wie dies in Ihrem onCreate:

Timer autoRefresh; 
autoRefresh=new Timer(); 
    autoRefresh.schedule(new TimerTask() { 
     @Override 
     public void run() { 
      runOnUiThread(new Runnable() { 
       public void run() { 
        getTimeLineData(token, page); 
       } 
      }); 
     } 
    }, 0, your_time_in_milliseconds); 

Sie können sogar das tun asynchron durch AsyncTask in Android verwenden.