Question

我见过“x：Static”表达式的示例，用于指定WPF XAML中绑定的ConverterParameter属性。但是，据我所知，Xamarin不允许您以这种方式设置属性。在后面的代码中指定ConverterParameter工作正常，使用StaticResource表达式工作正常，使用文字值，很好。有人可以指点我在Xamarin做一个这样的例子吗？

我的XAML：

<?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="OMS.ProductionPickupPage"
             xmlns:local="clr-namespace:OMS;assembly=OMS"
             Title="Production Pickup"
             Padding="5,5,5,5">
    <ContentPage.Resources>
        <ResourceDictionary>
            <local:PickerIndexConverter x:Key="PickerConverter" />
        </ResourceDictionary>
    </ContentPage.Resources>
<!-- ... -->
<Picker x:Name="LoadingFacility_Picker" Title="Loading Facility" SelectedIndex="{Binding SelectedLoadingFacility, Mode=OneWayToSource, 
Converter={StaticResource PickerConverter}, ConverterParameter={x:Static local:TestClass.TestMember}}" />

这是InitializeComponent（）中LoadFromXml方法抛出的异常：

System.Exception: Property  is not valid for this Expression

堆栈追踪：

[External Code] 
0xC in OMS.ProductionPickupPage.InitializeComponent at e:\Workspace\sumrallj\OMS\OMS\OMS\obj\Debug\ProductionPickupPage.xaml.g.cs:42,-1 C#
0x14 in OMS.ProductionPickupPage..ctor at e:\Workspace\sumrallj\OMS\OMS\OMS\ProductionPickupPage.xaml.cs:17,-1  C#
0x1 in OMS.App.GetMainPage at e:\Workspace\sumrallj\OMS\OMS\OMS\App.cs:14,-1    C#
0x22 in OMS.iOS.AppDelegate.FinishedLaunching at e:\Workspace\sumrallj\OMS\OMS\OMS.iOS\AppDelegate.cs:34,-1 C#
0xB in MonoTouch.UIKit.UIApplication.Main at /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:62,4  C#
0x3B in MonoTouch.UIKit.UIApplication.Main at /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:46,4 C#
0x8 in OMS.iOS.Application.Main at e:\Workspace\sumrallj\OMS\OMS\OMS.iOS\Main.cs:17,-1  C#

TestClass和TestMember都是静态的，我也尝试使用枚举。

namespace OMS
{
    public static class TestClass
    {
        public static string TestMember = "Test";
    }
}

使用带有ConverterParameter属性的x：Static表达式

0 个答案: