Question

我正在使用带有可点击项目的自定义适配器。问题是，当我滚动列表视图时，它会重新运行项目点击中存在的代码。如何禁用listview执行此操作？

以下是我的适配器示例：

public override View GetView(int position, View convertView, ViewGroup parent)
    {
        View row = convertView;
        if (row == null)
        {
            row = LayoutInflater.From(mContext).Inflate(Resource.Layout.InventoryPreview, null, false);

        }

        TextView txtInventoryName = row.FindViewById<TextView>(Resource.Id.txtInventoryName);

         Button ExtraBtn = row.FindViewById<Button>(Resource.Id.ExtrasBtn);




        txtInventoryName.Click += (sender, e) =>
        {
            var db = new SQLiteConnection(Connection.dpPath);
            db.CreateTable<OrderPreviewClass>();
            OrderPreviewClass tbl = new OrderPreviewClass();

            Connection.InventoryItemID = mitems[position].InventoryItemID;
            Connection.InventoryItemName = mitems[position].InventoryItemName;
            Connection.RetailPrice = mitems[position].InventoryItemPrice;
            Connection.Quantity = "1";

            tbl.CategoryID = Connection.CategoryID;
            tbl.InventoryItemID = Connection.InventoryItemID;
            tbl.Description = Connection.InventoryItemName;
            tbl.Quantity = Connection.Quantity;
            tbl.Price = Connection.RetailPrice;
            tbl.ExtrasPrice = "0";
            tbl.RealPrice = Connection.RetailPrice;
            tbl.Extras = ",";
            db.Insert(tbl);
            Toast toast = Toast.MakeText(mContext, "x1 " + txtInventoryName.Text, ToastLength.Short);
            toast.Show();

        };
        ExtraBtn.Click += (sender, e) =>
        {

            Connection.InventoryItemID = mitems[position].InventoryItemID;
            Connection.InventoryItemName = mitems[position].InventoryItemName;
            Connection.RetailPrice = mitems[position].InventoryItemPrice;
            Toast toast = Toast.MakeText(mContext, txtInventoryName.Text, ToastLength.Short);
            toast.Show();
            mContext.StartActivity(typeof(ExtrasPreviewMain));


        };



        return row;
    }

每次listview滚动时，如何停止重新运行代码？我应该使用ClickListener吗？

Answer 1

原因是您的单元格被回收，因此每次单元格被回收时，您都会向文本控件和按钮添加另一个事件 - C＃中的事件是多播委托，因此可以触发多个事物。

每次回收单元格时，都会添加另一个事件处理程序。

简单修复是将两个处理程序都提取到方法或本地函数而不是lambdas中，并且在添加之前总是删除处理程序。

类似的东西：

void TextHandler(object sender, EventArgs args) =
{
   var db = new SQLiteConnection(Connection.dpPath);
   ... // rest of the handler here
}

// remove the handler - doesn't matter if it's not already set
txtInventoryName.Click -= TextHandler;

// set the handler
txtInventoryName.Click += TextHandler;

滚动我的列表视图重新运行我的所有项目的代码

1 个答案: