Xamarin安卓Gridview與CustomAdapter ART問題

Question

我有android和gridview和customadapter問題。 （物品細胞包含imageview，3個文字瀏覽和2個按鈕）

2物理設備（1與Android 4.3（達爾維克），1與Android 5.1.1（藝術））。

在dalvik設備上，gridview滾動非常平滑。 在ART設備上，gridview滾動速度非常慢。

圖像由getview中調用的asynctask加載。

有什麼建議嗎？

下面是我的GetView代碼片段：

public override View GetView(int position, View convertView, ViewGroup parent) 
    { 
     var item = _orderItemLoader.OrderItems[position]; 

     View itemView = LayoutInflater.From(_context).Inflate(Resource.Layout.OrderItemCell, parent, false); 

     var tvDisplayName = itemView.FindViewById<TextView>(Resource.Id.tvDisplayName); 
     var tvDisplayAmount = itemView.FindViewById<TextView>(Resource.Id.tvDisplayAmount); 
     var tvDisplayCount = itemView.FindViewById<TextView>(Resource.Id.textViewQuantity); 

     foreach (var _item in _orderItemLoader.OrderItems) 
     { 
      if (GetItemId(position) == _item.ItemId) 
      { 
       tvDisplayCount.Text = _item.Count.ToString(); 
       break; 
      } 
     } 

     var btnPlus = itemView.FindViewById<Button>(Resource.Id.buttonPlus); 
     btnPlus.Focusable = false; 
     btnPlus.FocusableInTouchMode = false; 
     btnPlus.Clickable = true; 
     btnPlus.Tag = position; 
     btnPlus.Click += (s, e) => 
     { 
      int pos = (int)((Button)s).Tag; 
      foreach (var itm in _orderItemLoader.OrderItems) 
      { 
       if (item.ItemId == GetItemId(position)) 
       { 
        item.Count += 1; 

        tvDisplayCount.Text = item.Count.ToString(); 
        break; 
       } 
      } 
     }; 
     var btnMinus = itemView.FindViewById<Button>(Resource.Id.buttonMinus); 
     btnMinus.Focusable = false; 
     btnMinus.FocusableInTouchMode = false; 
     btnMinus.Clickable = true; 
     btnMinus.Tag = position; 
     btnMinus.Click += (s, e) => 
     { 
      int pos = (int)((Button)s).Tag; 
      var tmpItem = GetItem(pos); 
      if (tmpItem != null) 
      { 
       if (tmpItem.Count > 1) 
        tmpItem.Count -= 1; 
       else 
        tmpItem.Count = 0; 

       tvDisplayCount.Text = tmpItem.Count.ToString(); 
      }     
     }; 
     var imgThumbail = itemView.FindViewById<ImageView>(Resource.Id.imgThumbnail); 

     imgThumbail.SetScaleType(ImageView.ScaleType.CenterCrop); 
     imgThumbail.SetPadding(8, 8, 8, 8); 

     tvDisplayName.Text = item.ItemName; 
     tvDisplayName.SetTextColor(Android.Graphics.Color.Black); 

     tvDisplayAmount.Text = ServiceManager.GetCurrency(item.Amount); 
     tvDisplayAmount.SetTextColor(Android.Graphics.Color.Black); 

     tvDisplayCount.SetTextColor(Android.Graphics.Color.Black); 

     new SetImageBitmapTask(item, imgThumbail, _activity).Execute(""); 

     return itemView; 
    } 

Answer 1

我提高了使用ViewHolder列表的表現，我會告訴你一個例子，這樣就可以實現

ViewHolder：

public class StoreRecomendadaViewHolder : Object 
    { 
     public ImageView imgView { set; get; } 
     public TextView txtView { set; get; } 
    } 

GetView：

public override View GetView(int position, View convertView, ViewGroup parent) 
    { 
     StoreRecomendadaViewHolder holder = null; 
     var view = convertView; 
     if (view != null) 
      holder = view.Tag as StoreRecomendadaViewHolder; 

     var item = items[position]; 

     if (holder == null) 
     { 
      holder = new StoreRecomendadaViewHolder(); 

      if (view == null) 
      { 
       Activity _activity = context; 
       view = _activity.LayoutInflater.Inflate(Resource.Layout.ItemStoreRecomendada, null); 
      } 

      holder.imgView = view.FindViewById<ImageView>(Resource.Id.imgView); 
      holder.txtView = view.FindViewById<TextView>(Resource.Id.txtView); 

      view.Tag = holder; 
     } 
     holder.txtView.SetText(item.NombreComercial, TextView.BufferType.Normal); 
     return view; 
    }