GridViewはHTTP応答で非常に長い時間をレンダしました

Question

私はAndroid開発の初心者です。私はhttp要求のためにこのライブラリを使用していますhttps://github.com/loopj/android-async-http。

そして、私はGridViewで応答JSONをレンダリングするのに非常に時間がかかります。プリローダとして進行状況ダイアログを使用していますが、listviewがレンダリングされる前に削除されています。どのように私はこの問題を解決することができますか？ありがとうございました。

次は、このGridViewのスクリーンショットです。ここで

は、この活動の実施です。

public class LikesActivity extends BottomBarActivity //some custom activity { 
List<Anticafe> mAnticafes = new ArrayList<>(); 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_likes); 

     /*some code*/ 



     Request.post(Constants.POST_SEARCH_API_LINK, params, new AsyncHttpResponseHandler() { 
       @Override 
       public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) { 
        Gson gson = new GsonBuilder().create(); 
        Request request = gson.fromJson(new String(responseBody), Request.class); 

        mAnticafes = request.getAnticafes(); 
        renderListView() 
       } 

       @Override 
       public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable error) { 
        hideProcessDialog(); 
       } 
      }); 


    } 

    private void renderListView() { 
     GridView likesList = (GridView) findViewById(R.id.likes_list); 
     AnticafeAdapter anticafeAdapter = new AnticafeAdapter(this, mAnticafes); 
     anticafeAdapter.setWidth(getWidth()); 
     likesList.setAdapter(anticafeAdapter); 
    } 
} 

ここにはアダプタの完全な実装があります。

public class AnticafeAdapter extends BaseAdapter{ 

    public static final String TAG = "image-request"; 
    private Context mContext; 
    private List<Anticafe> mAnticafes = new ArrayList<>(); 
    private Client mClient; 
    private View mConvertView; 
    private int mWidth; 

    public AnticafeAdapter(Context context, List<Anticafe> anticafes) { 
     mContext = context; 
     mAnticafes = anticafes; 
    } 

    public void setWidth(int mWidth) { 
     this.mWidth = (int) (mWidth/4.7); 
    } 

    @Override 
    public int getCount() { 
     return mAnticafes.size(); 
    } 

    @Override 
    public Anticafe getItem(int position) { 
     return mAnticafes.get(position); 
    } 

    @Override 
    public long getItemId(int position) { 
     return getItem(position).getId(); 
    } 

    @Override 
    public View getView(int position, View convertView, ViewGroup parent) { 

     final Anticafe anticafe = getItem(position); 
     mClient = AnticafeApplication.getInstanse().getClient(); 
     mConvertView = convertView; 
     final ProgressDialog processDialog = new ProgressDialog(mContext); 

     processDialog.setMessage("Информация обновляется. Пожалуйста, подождите."); 

     if(mConvertView == null) { 
      mConvertView = LayoutInflater.from(mContext).inflate(R.layout.adapter_popular, null); 
     } 

     ImageView cover = (ImageView) mConvertView.findViewById(R.id.cover); 
     CircularImageView logo = (CircularImageView) mConvertView.findViewById(R.id.logo); 
     final ImageView like = (ImageView) mConvertView.findViewById(R.id.like); 
     final TextView likesCount = (TextView) mConvertView.findViewById(R.id.likes_count); 
     TextView name = (TextView) mConvertView.findViewById(R.id.name); 
     TextView price = (TextView) mConvertView.findViewById(R.id.price); 

     if(mClient != null) { 
      final boolean liked = mClient.containsLike(anticafe.getId()); 
      if(liked) { 
       like.setImageDrawable(mContext.getResources().getDrawable(R.drawable.ic_like)); 
      } else { 
       like.setImageDrawable(mContext.getResources().getDrawable(R.drawable.ic_unlike)); 
      } 
     } else { 
      like.setImageDrawable(mContext.getResources().getDrawable(R.drawable.ic_unlike)); 
     } 

     likesCount.setText(String.valueOf(anticafe.getTotalLikes())); 
     name.setText(anticafe.getName()); 
     price.setText(anticafe.getPrices()); 

     Picasso.with(mContext).load(anticafe.getAttachment().getCover()).networkPolicy(NetworkPolicy.OFFLINE).into(cover); 
     Picasso.with(mContext).load(anticafe.getAttachment().getLogo()).resize(mWidth, mWidth).into(logo); 

     likeMechanism(anticafe, processDialog, like, likesCount); 

     name.setOnClickListener(anticafeOpenActivityEvent(anticafe.getId())); 
     price.setOnClickListener(anticafeOpenActivityEvent(anticafe.getId())); 
     logo.setOnClickListener(anticafeOpenActivityEvent(anticafe.getId())); 
     cover.setOnClickListener(anticafeOpenActivityEvent(anticafe.getId())); 

     BottomBarActivity activity = (BottomBarActivity) this.mContext; 
     activity.hideProcessDialog(); 

     return mConvertView; 
    } 

    private void likeMechanism(final Anticafe anticafe, final ProgressDialog processDialog, final ImageView like, final TextView likesCount) { 
     like.setOnClickListener(new OnClickListener() { 
      @Override 
      public void onClick(View v) { 

       if (mClient == null) { 
        AlertDialog.Builder builder = new AlertDialog.Builder(mContext); 
        builder.setTitle("Вы не авторизованы") 
          .setMessage("До тех пор, пока вы не пройдете авторизацию, вы не сможете пользоваться некоторым функционалом нашего приложение. Авторизация займет всего лишь пару минут.") 
          .setCancelable(false) 
          .setNegativeButton("Скрыть", new DialogInterface.OnClickListener() { 
           @Override 
           public void onClick(DialogInterface dialog, int which) { 
           } 
          }) 
          .setPositiveButton("Авторизоваться", new DialogInterface.OnClickListener() { 
           @Override 
           public void onClick(DialogInterface dialog, int which) { 
            Intent intent = new Intent(mContext, AuthActivity.class); 
            mContext.startActivity(intent); 
            Activity activity = ((Activity) mContext); 
            activity.overridePendingTransition(R.anim.slide_in_left, R.anim.slide_in_right); 
           } 
          }); 

        AlertDialog dialog = builder.create(); 
        dialog.show(); 

       } else { 

        processDialog.show(); 

        RequestParams params = new RequestParams(); 
        params.add("anticafe_id", anticafe.getId() + ""); 
        AuthedRequest.post(Constants.LIKE_API_LINK, params, new AsyncHttpResponseHandler() { 
         @Override 
         public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) { 
          processDialog.hide(); 
          Gson gson = new GsonBuilder().create(); 
          try { 
           LikeResponse response = gson.fromJson(new String(responseBody, Constants.UTF_8), LikeResponse.class); 
           if (response.getLikeStatus().equals("unliked")) { 
            like.setImageDrawable(mContext.getResources().getDrawable(R.drawable.ic_unlike)); 
           } else if (response.getLikeStatus().equals("liked")) { 
            like.setImageDrawable(mContext.getResources().getDrawable(R.drawable.ic_like)); 
           } 
           likesCount.setText(String.valueOf(response.getTotalLikes())); 
          } catch (UnsupportedEncodingException e) { 
           e.printStackTrace(); 
          } finally { 
           processDialog.hide(); 
          } 
         } 

         @Override 
         public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable error) { 
          try { 
           Log.d("json", "onSuccess: " + new String(responseBody, Constants.UTF_8)); 
          } catch (UnsupportedEncodingException e) { 
           e.printStackTrace(); 
          } finally { 
           processDialog.hide(); 
          } 
         } 

        }); 
       } 
      } 
     }); 
    } 

    private OnClickListener anticafeOpenActivityEvent(final int id) { 
     return new OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       Bundle bundle = new Bundle(); 
       bundle.putInt("entity_id", id); 
       ((BottomBarActivity) mContext).openNewActivity(AnticafeActivity.class, bundle); 
      } 
     }; 
    } 

    private static class LikeResponse { 

     @SerializedName("status") 
     @Expose 
     private Integer status; 
     @SerializedName("error") 
     @Expose 
     private Boolean error; 
     @SerializedName("likeStatus") 
     @Expose 
     private String likeStatus; 
     @SerializedName("totalLikes") 
     @Expose 
     private Integer totalLikes; 

     public LikeResponse(Integer status, Boolean error, String likeStatus, Integer totalLikes) { 
      this.status = status; 
      this.error = error; 
      this.likeStatus = likeStatus; 
      this.totalLikes = totalLikes; 
     } 

     /** 
     * 
     * @return 
     * The status 
     */ 
     public Integer getStatus() { 
      return status; 
     } 

     /** 
     * 
     * @param status 
     * The status 
     */ 
     public void setStatus(Integer status) { 
      this.status = status; 
     } 

     /** 
     * 
     * @return 
     * The error 
     */ 
     public Boolean getError() { 
      return error; 
     } 

     /** 
     * 
     * @param error 
     * The error 
     */ 
     public void setError(Boolean error) { 
      this.error = error; 
     } 

     /** 
     * 
     * @return 
     * The likeStatus 
     */ 
     public String getLikeStatus() { 
      return likeStatus; 
     } 

     /** 
     * 
     * @param likeStatus 
     * The likeStatus 
     */ 
     public void setLikeStatus(String likeStatus) { 
      this.likeStatus = likeStatus; 
     } 

     /** 
     * 
     * @return 
     * The totalLikes 
     */ 
     public Integer getTotalLikes() { 
      return totalLikes; 
     } 

     /** 
     * 
     * @param totalLikes 
     * The totalLikes 
     */ 
     public void setTotalLikes(Integer totalLikes) { 
      this.totalLikes = totalLikes; 
     } 

    } 
} 

Answer 1

あなたは何が問題なのか正確に言うコードを表示しません。
しかし、そのようなピカソなどのWebからの画像取り込み用のサードパーティのライブラリを使用して、より良いどのような方法：
http://square.github.io/picasso
このライブラリがスムーズにあなたのイメージをロードして、自身でキャッシュを疥癬。
UPDATE：
その他のオプションは、あなたのアダプタクラスであなたのGetViewメソッドでviewHolderデザインパターンを使用していけないということです。
現在のコードでは、gridViewのすべてのセルでfindViewByIdメソッドを呼び出しますが、初めて呼び出す必要があります。 この問題を解決するには、viewHolderデザインパターンを使用する必要があります。

ビューホルダー付きGetViewメソッドのexampple：ビューホルダークラスの

@Override 
public View getView(int position, View convertView, ViewGroup parent) { 

    ViewHolderItem viewHolder; 

    /* 
    * The convertView argument is essentially a "ScrapView" as described is Lucas post 
    * http://lucasr.org/2012/04/05/performance-tips-for-androids-listview/ 
    * It will have a non-null value when ListView is asking you recycle the row layout. 
    * So, when convertView is not null, you should simply update its contents instead of inflating a new row layout. 
    */ 
    if(convertView==null){ 

     // inflate the layout 
     LayoutInflater inflater = ((Activity) mContext).getLayoutInflater(); 
     convertView = inflater.inflate(layoutResourceId, parent, false); 

     // well set up the ViewHolder 
     viewHolder = new ViewHolderItem(); 
     viewHolder.textViewItem = (TextView) convertView.findViewById(R.id.textViewItem); 

     // store the holder with the view. 
     convertView.setTag(viewHolder); 

    }else{ 
     // we've just avoided calling findViewById() on resource everytime 
     // just use the viewHolder 
     viewHolder = (ViewHolderItem) convertView.getTag(); 
    } 

    // object item based on the position 
    ObjectItem objectItem = data[position]; 

    // assign values if the object is not null 
    if(objectItem != null) { 
     // get the TextView from the ViewHolder and then set the text (item name) and tag (item ID) values 
     viewHolder.textViewItem.setText(objectItem.itemName); 
     viewHolder.textViewItem.setTag(objectItem.itemId); 
    } 

    return convertView; 

} 

例（このクラスでは、ビューの要素を定義する）：

static class ViewHolderItem { 
    TextView textViewItem; 
} 

詳細はこの参照してください。
をhttps://www.javacodegeeks.com/2013/09/android-viewholder-pattern-example.html