listview中selecteditem的背景颜色xamarin.forms

Question

当在Xamarin.forms中使用ListView时，在选择一个项目时，该项目仍然像一个相当丑陋的背景颜色。我可以禁用此功能吗？

这里是我的代码：

<StackLayout> 
    <ListView x:Name="FoodList" HasUnevenRows="True" CachingStrategy="RecycleElement" ItemTapped="OnItemTapped"> 
    <ListView.ItemTemplate> 
     <DataTemplate> 
     <ViewCell> 
      <StackLayout Padding="0,15,0,0" > 
      <StackLayout Orientation="Horizontal" BackgroundColor="White" > 
      <Image Source="{Binding image_url}" Aspect="AspectFill" HeightRequest="200" WidthRequest="200"/> 
      <StackLayout Orientation="Vertical"> 
       <Label Text="{Binding food_name}" TextColor="Black" Style="{StaticResource MainLisTtext}" /> 
       <Label Text="{Binding price}" TextColor="Black" Style="{StaticResource SubLisTtext}" /> 
       <Label Text="{Binding food_description}" TextColor="Black" Style="{StaticResource SubLisTtext}" /> 
      </StackLayout> 
      </StackLayout> 
      </StackLayout> 
     </ViewCell>vc 
     </DataTemplate> 
    </ListView.ItemTemplate> 
    </ListView> 
</StackLayout> 

Answer 1

这可以通过使用自定义渲染

iOS的自定义呈现

编辑iOS上SelectionStyle属性来完成。

下面的示例将UITableViewCellSelectionStyle设置为None。

using System; 

using UIKit; 

using Xamarin.Forms; 
using Xamarin.Forms.Platform.iOS; 

using ListViewSample.iOS; 

[assembly: ExportRenderer(typeof(ViewCell), typeof(ViewCellItemSelectedCustomRenderer))] 
namespace ListViewSample.iOS 
{ 
    public class ViewCellItemSelectedCustomRenderer : ViewCellRenderer 
    { 
     public override UITableViewCell GetCell(Cell item, UITableViewCell reusableCell, UITableView tv) 
     { 
      var cell = base.GetCell(item, reusableCell, tv); 

      cell.SelectionStyle = UITableViewCellSelectionStyle.None; 

      return cell; 
     } 
    } 
} 

Android的自定义呈现

1. 创建一个新的绘制，ViewCellBackground.xml并将其保存到Resources>drawable文件夹：

   <?xml version="1.0" encoding="UTF-8" ?> 
   <selector xmlns:android="http://schemas.android.com/apk/res/android"> 
       <item android:state_pressed="true" > 
        <shape android:shape="rectangle"> 
         <!--Change the selected color by modifying this hex value--> 
         <solid android:color="#FFFFFF" /> 
        </shape> 
       </item> 
       <item> 
        <shape android:shape="rectangle"> 
         <solid android:color="#FFFFFF" /> 
        </shape> 
       </item> 
   </selector> 
   

2. 为ViewCell

   创建自定义呈现

   using System; 
   
   using Xamarin.Forms; 
   using Xamarin.Forms.Platform.Android; 
   
   using ListViewSample.Droid; 
   
   [assembly: ExportRenderer(typeof(ViewCell), typeof(ViewCellItemSelectedCustomRenderer))] 
   namespace ListViewSample.Droid 
   { 
       public class ViewCellItemSelectedCustomRenderer : ViewCellRenderer 
       { 
        protected override Android.Views.View GetCellCore(Cell item, Android.Views.View convertView, Android.Views.ViewGroup parent, Android.Content.Context context) 
        { 
         var cell = base.GetCellCore(item, convertView, parent, context); 
   
         cell.SetBackgroundResource(Resource.Drawable.ViewCellBackground); 
   
         return cell; 
        } 
       } 
   } 
   

编辑：删除不执行自定义渲染器

---

样品Xamarin.Forms的ListView应用

using System; 
using System.Collections.Generic; 

using Xamarin.Forms; 

namespace ListViewSample 
{ 
    public class CustomViewCell : ViewCell 
    { 
     public CustomViewCell() 
     { 
      View = new Label 
      { 
       Text = "Hello World" 
      }; 
     } 
    } 

    public class ListViewContentPage : ContentPage 
    { 
     public ListViewContentPage() 
     { 
      var itemSourceList = new List<CustomViewCell>(); 
      itemSourceList.Add(new CustomViewCell()); 
      itemSourceList.Add(new CustomViewCell()); 

      var listView = new ListView(); 
      listView.ItemTemplate = new DataTemplate(typeof(CustomViewCell)); 
      listView.ItemsSource = itemSourceList; 
      listView.SeparatorVisibility = SeparatorVisibility.None; 

      Content = listView; 
     } 
    } 

    public class App : Application 
    { 
     public App() 
     { 
      // The root page of your application 

      MainPage = new NavigationPage(new ListViewContentPage()); 
     } 
    } 
}