Xamarin表单列表视图将焦点设置为选定行

Question

我正在使用ListView，在每个单元格中，我有一个标签和右侧的条目。当我点击输入框时，键盘会显示，但如果我点击该行而不点击输入框键盘则不会。如何在选择行时使条目聚焦？

<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms" 
	xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" 
	x:Class="Sample7.StartPage">


	<ContentPage.ToolbarItems>
		<ToolbarItem Text="Scanner" Icon="camera.png">
		</ToolbarItem>

		<ToolbarItem Text="Notes" Icon="notes.png" >
		</ToolbarItem>
	</ContentPage.ToolbarItems>


	<ScrollView>
		<StackLayout Padding="20,20,20,0">
				<Picker Title="Location" HorizontalOptions="FillAndExpand" Items="NuseedDataManager.getWarehouses()"/>

				<StackLayout Orientation="Horizontal" Padding="0,20,0,20">
					<Label Text="Show All" HorizontalOptions="FillAndExpand" />
					<Switch IsToggled="true"  HeightRequest="50" WidthRequest="250"/>
				</StackLayout>

				<ListView x:Name="SkuListView" RowHeight="60">
					<ListView.ItemTemplate>
						<DataTemplate>
							<ViewCell>

								<StackLayout Orientation="Horizontal" BackgroundColor="{Binding BackgroundColor}">
									<Label Text="TITLE\nawesome1awesome1awesome1awesome1awesome1awesome1awesome1awesome1awesome1awesome1awesome1awesome1" HorizontalOptions="FillAndExpand" FontSize="12"/>
									<Entry Text="{Binding CountText}" WidthRequest="70" Keyboard="Numeric" IsFocused="{Binding IsEntryFocused}" />
								</StackLayout>

							</ViewCell>
						</DataTemplate>
					</ListView.ItemTemplate>
				</ListView>

				<StackLayout Padding="0,20,0,20">
					<Button Text="Verify" />
				</StackLayout>
		</StackLayout>
	</ScrollView>


</ContentPage>

namespace Sample7
{
	public partial class StartPage : ContentPage
	{
		ObservableCollection<Cell> skus ;
		public StartPage ()
		{
			InitializeComponent ();

			skus = new ObservableCollection<Cell>();


			for (int i = 0; i < 30; i++) {

				if (i < 10) {
					skus.Add(new Cell(){
						BackgroundColor = Color.Aqua,
						CountText = "1"
					});
				} else {

					skus.Add (new Cell () {
						BackgroundColor = Color.Red,
						CountText = "1"
					});

				}
			}

			SkuListView.ItemsSource = skus;

			SkuListView.HeightRequest = SkuListView.RowHeight* skus.Count ()+40;

			SkuListView.ItemSelected += (sender, e) => {
				Cell c = (Cell)e.SelectedItem;

				c.IsEntryFocused = true;
				c.BackgroundColor = Color.Olive;
				c.CountText = "45";

			};
		}
	}
}

Answer 1

为条目创建新行为，并将其BindingContext设置为ListView实例。如果所选行发生更改（ItemSelected事件），请将所选项目与当前行的项目（entry.BindingContext）进行比较。如果匹配，请关注该条目。

<Entry Text="{Binding CountText}" WidthRequest="70" Keyboard="Numeric">
    <Entry.Behaviors>
        <local:FocusEntryFromSelectedRowBehavior BindingContext="{x:Reference SkuListView}" />
    </Entry.Behaviors>
</Entry>

public class FocusEntryFromSelectedRowBehavior : Behavior<Entry>
{
    public Entry AssociatedEntry{ get; private set; }

    protected override void OnAttachedTo(Entry entry)
    {
        base.OnAttachedTo(entry);
        AssociatedEntry = entry;            
        ((ListView)BindingContext).ItemSelected += MyView_ItemSelected;           
    }

    private void MyView_ItemSelected(object sender, SelectedItemChangedEventArgs e)
    {            
        if (AssociatedEntry.BindingContext == e.SelectedItem)
        {
            AssociatedEntry.Focus();
        }
    }

    protected override void OnDetachingFrom(Entry entry)
    {            
        ((ListView)BindingContext).ItemSelected -= MyView_ItemSelected;
        base.OnDetachingFrom(entry);
    }
}

Answer 2

您需要调用Entry的Focus（）方法。