我不能有两个不同的数据源来绑定到我的不同全景项目

Question

我为两个不同的绑定源创建了两个不同的类。 Model1.cs 和 Model2.cs 。

Model1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MultiBindingTest
{
    class Model1
    {
        public string str1 { get; set; }
        public string str2 { get; set; }
        public Model1(string one , string two)
        {
            str1 = one;
            str2 = two;
        }
    }
}

Model2.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MultiBindingTest
{
    class Model2
    {
        public string one { get; set; }
        public string two { get; set; }
        public Model2 (string str1 , string str2)
        {
            one = str1;
            two = str2;
        }
    }
}

我有另外两个类，我希望它们成为数据源，它们被命名为 vm1.cs 和 vm2.cs； vm1 有一个类类型 Model1 的可观察集合，而 Vm2 有一个类类型 model2 的可观察集合，我在它们的构造函数中填充了数据。

Vm1.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MultiBindingTest
{
    class vm1:NotificationObject
{
        private static ObservableCollection<Model1> _testVM1;
        public static ObservableCollection<Model1> TestVM1
        {
            get { return _testVM1; }
            set { _testVM1 = value; }
        }
        public vm1()
        {
            TestVM1 = new ObservableCollection<Model1>();
            TestVM1.Add(new Model1("1", "Model1"));
            TestVM1.Add(new Model1("2", "Model1"));
            TestVM1.Add(new Model1("3", "Model1"));
        }
    }
}

VM2.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

 namespace MultiBindingTest
{
    class vm2:NotificationObject
    {
        private static ObservableCollection<Model2> _testVM2;
        public static ObservableCollection<Model2> TestVM2
        {
            get { return _testVM2; }
            set { _testVM2 = value; }
        }
        public vm2()
        {
            TestVM2 = new ObservableCollection<Model2>();
            TestVM2.Add(new Model2("1", "Model2"));
            TestVM2.Add(new Model2("2", "Model2"));
            TestVM2.Add(new Model2("3", "Model2"));
        }
    }
}

通知对象

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MultiBindingTest
{
    public class NotificationObject : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;

        public void RaisePropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }
}

我想将 Vm1 绑定为panoramaitem1 的数据上下文，将vm2 绑定为panoramaItem2 的数据上下文，这样我就可以在每个中绑定longlistselector 项。但我得到一个 xamlParseException ，我做错了什么。

主页 Xaml

<phone:PhoneApplicationPage
    x:Class="MultiBindingTest.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
    xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:MultiBindingTest"
    mc:Ignorable="d"
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="Portrait" Orientation="Portrait"
    shell:SystemTray.IsVisible="True">

    <phone:Panorama x:Name="mainPanorama"
                    Title="Binding Test Application">
        <phone:PanoramaItem x:Name="ItemOne"
                            Header="Item One">
            <phone:LongListSelector>
                <phone:LongListSelector.DataContext>
                    <local:vm1 />
                </phone:LongListSelector.DataContext>
                <phone:LongListSelector.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Vertical">
                            <TextBlock Text="{Binding Path=str1}"/>
                            <TextBlock Text="{Binding Path=str2}" />
                        </StackPanel>
                    </DataTemplate>
                </phone:LongListSelector.ItemTemplate>
            </phone:LongListSelector>

        </phone:PanoramaItem>
        <phone:PanoramaItem x:Name="ItemTwo"
                            Header="Item Two">
            <phone:LongListSelector>
                <phone:LongListSelector.DataContext>
                    <local:vm2 />
                </phone:LongListSelector.DataContext>
                <phone:LongListSelector.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Vertical">
                            <TextBlock Text="{Binding Path=one}" />
                            <TextBlock Text="{Binding Path=two}" />
                        </StackPanel>
                    </DataTemplate>
                </phone:LongListSelector.ItemTemplate>
            </phone:LongListSelector>

        </phone:PanoramaItem>
    </phone:Panorama>
</phone:PhoneApplicationPage>

附加信息 所有的类都在同一个命名空间中

XamlParseException

 System.Windows.Markup.XamlParseException occurred
  HResult=-2146233087
  Message=Cannot create instance of type 'MultiBindingTest.vm1' [Line: 23 Position: 33]
  Source=System.Windows
  LineNumber=23
  LinePosition=33
  StackTrace:
       at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator)
       at MultiBindingTest.MainPage.InitializeComponent()
       at MultiBindingTest.MainPage..ctor()
  InnerException: 

Answer 1

公开您的视图模型类：

public class vm1:NotificationObject{...}
public class vm2:NotificationObject{...}