将DataContext窗口绑定到ViewModel

时间:2017-05-04 11:58:07

标签: c# wpf xaml mvvm datacontext

好的,我尝试了几种方法,但没有一种方法可以用于我的情况。我有一个带有单个ComboBox的简单窗口。我正在将代码更改为MVVM,所以现在一切仍然在Code-Behind中,应该转到ViewModel等。
但即使在第一步(将ViewModel绑定到View / Window),我似乎也无法将它们绑定在一起。

我的窗口XAML:

<Window x:Class="CustomerGuidance.ClientWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:VM="clr-namespace:CustomerGuidance.ViewModels"
    Title="Stop'n'Go - Client" Height="22" Width="229"
    Loaded="ClientWindow_OnLoaded" WindowStyle="None" 
    WindowStartupLocation="Manual" Top="0" Left="0"
    ResizeMode="NoResize" ShowInTaskbar="False" Topmost="True">
<Window.DataContext>
    <VM:EmployeeViewModel />
</Window.DataContext>
<Canvas Background="Gainsboro">
    <ComboBox Name="EmployeesComboBox"
              ItemsSource="{Binding EmployeeEntries}"
              Width="192" FontFamily="Arial" FontSize="14">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <StackPanel Orientation="Horizontal">
                    <TextBlock Text="{Binding Lastname}" />
                    <TextBlock Text=", " />
                    <TextBlock Text="{Binding Surname}" />
                </StackPanel>
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>
</Canvas>

ViewModel如下所示:

using System.Collections.ObjectModel;
using System.ComponentModel;

namespace CustomerGuidance.ViewModels
{
    public class EmployeeViewModel : INotifyPropertyChanged
    {
        public EmployeeViewModel()
        {
        }

        public static ObservableCollection<ServerWindow.EmployeeEntry> EmployeeEntries { get; set; } = new ObservableCollection<ServerWindow.EmployeeEntry>();

        private string _surname;
        private string _lastname;
        private int _id;

        public string Surname
        {
            get { return _surname; }
            set
            {
                if (_surname == value)
                    return;
                _surname = value;
                NotifyPropertyChanged("Surname");
            }
        }

        public string Lastname
        {
            get { return _lastname; }
            set
            {
                if (_lastname == value)
                    return;
                _lastname = value;
                NotifyPropertyChanged("Lastname");
            }
        }

        public int Id
        {
            get { return _id; }
            set
            {
                if (_id == value)
                    return;
                _id = value;
                NotifyPropertyChanged("Id");
            }
        }

        public virtual event PropertyChangedEventHandler PropertyChanged;

        protected virtual void NotifyPropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            handler?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

我收到以下错误消息:名称“EmployeeViewModel”在命名空间“clr-namespace:CustomerGuidance.ViewModels”中不可用。
现在问题:我缺少什么?我怎么能绑定ViewModel到我的窗口-XAML?

1 个答案:

答案 0 :(得分:1)

您应该为错误构建代码以消失 这是因为设计器在构建之前依赖于(程序)所在的程序集中尚未提供名称空间。