Xaml 从BindableLayout检索ItemsSource
我有一个Xaml 从BindableLayout检索ItemsSource,xaml,xamarin,xamarin.forms,data-binding,Xaml,Xamarin,Xamarin.forms,Data Binding,我有一个FlexLayout和一个bindableayout <FlexLayout BindableLayout.ItemsSource="{Binding CardItems}" x:Name="SourceLayout" Background="green" Direction="Row" Wrap="Wrap">
FlexLayout
和一个bindableayout
<FlexLayout BindableLayout.ItemsSource="{Binding CardItems}" x:Name="SourceLayout" Background="green"
Direction="Row" Wrap="Wrap">
<BindableLayout.ItemTemplate>
<DataTemplate>
<ContentView>
<Frame CornerRadius="20" Padding="0" WidthRequest="150" Margin="10"
HeightRequest="150"
BackgroundColor="{Binding .,
Converter={StaticResource AlternateColorConverter},
ConverterParameter={x:Reference SourceLayout}}">
<StackLayout>
<StackLayout.GestureRecognizers>
<TapGestureRecognizer Command="{Binding Path=BindingContext.CardItemNavCommand, Source={x:Reference SourceLayout}}"
CommandParameter="{Binding NavTarget}"/>
</StackLayout.GestureRecognizers>
<Label Text="{Binding Text}" TextColor="Black" FontSize="20" VerticalOptions="FillAndExpand"/>
<Label Text="{Binding Text}" TextColor="Black" FontSize="20" VerticalOptions="FillAndExpand"/>
</StackLayout>
</Frame>
</ContentView>
</DataTemplate>
</BindableLayout.ItemTemplate>
</FlexLayout>
是否可以获取转换器中当前项目的索引,以便我可以相应地更改颜色?我知道这可以通过ListView
实现,因为我可以访问items源属性,但无法从bindablellayout
访问资源
<FlexLayout BindableLayout.ItemsSource="{Binding CardItems}" x:Name="SourceLayout" Background="green"
Direction="Row" Wrap="Wrap">
<BindableLayout.ItemTemplate>
<DataTemplate>
<ContentView>
<Frame CornerRadius="20" Padding="0" WidthRequest="150" Margin="10"
HeightRequest="150"
BackgroundColor="{Binding .,
Converter={StaticResource AlternateColorConverter},
ConverterParameter={x:Reference SourceLayout}}">
<StackLayout>
<StackLayout.GestureRecognizers>
<TapGestureRecognizer Command="{Binding Path=BindingContext.CardItemNavCommand, Source={x:Reference SourceLayout}}"
CommandParameter="{Binding NavTarget}"/>
</StackLayout.GestureRecognizers>
<Label Text="{Binding Text}" TextColor="Black" FontSize="20" VerticalOptions="FillAndExpand"/>
<Label Text="{Binding Text}" TextColor="Black" FontSize="20" VerticalOptions="FillAndExpand"/>
</StackLayout>
</Frame>
</ContentView>
</DataTemplate>
</BindableLayout.ItemTemplate>
</FlexLayout>
是否有可能获得转换器中当前项目的索引,以便我可以相应地更改颜色
bindablellayout
是一个静态类,因此我们无法从布局中获取它来获取itemsSource
对于此函数,请尝试在模型类中创建“Identifier”属性,并为backgroundColor设置绑定。然后获取converter类中的值,以从数据收集中获取当前项的索引。根据索引指定背景色
检查代码:
App.xaml.cs
public partial class App : Application
{
public static TestPageViewModel viewModel;
public App()
{
InitializeComponent();
viewModel = new TestPageViewModel();
MainPage = new NavigationPage(new TestPage());
}
}
Page.xaml
<StackLayout BindableLayout.ItemsSource="{Binding DataCollection}" ...>
<BindableLayout.ItemTemplate>
<DataTemplate>
<Grid Padding="0,2,3,0" BackgroundColor="{Binding Identifier, Converter={StaticResource _converter}}">
...
</Grid>
</DataTemplate>
</BindableLayout.ItemTemplate>
</StackLayout>
模范班
public class TestPageModel
{
public string Content { get; set; }
public string Identifier { get; set; }
}
值转换器类
public class TestPageValueConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
var index = GetValue(value);
switch (index)
{
case 1:
return Color.LightBlue;
break;
case 2:
return Color.LightPink;
break;
case 3:
return Color.LightYellow;
break;
default:
break;
}
return Color.White;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
return -1;
}
double GetValue(object value)
{
var viewModel = App.viewModel;
foreach (var item in viewModel.DataCollection)
{
if (item.Identifier == (string)value)
{
return viewModel.DataCollection.IndexOf(item) + 1;
}
}
return -1;
}
}
这回答了你的问题吗?我已经看过那个链接了。我在寻找一个更简单的解决方案。。。