WPF與ResourceDictionary的MVVM數據綁定MVVM

Question

我試圖用ResourceDictionary中的ViewModel綁定視圖，但它不起作用。

該應用程序是非常簡單的窗口與2個文本框。當我將文本鍵入textbox1時，textbox2必須獲取相同的文本。當然，我的視圖中的文本框必須綁定到ViewModel中的屬性。

我新的WPF，我開始綁定視圖和的ViewModels的方式是在視圖的代碼隱藏：

DataContext = new MyViewModel(); 

現在我想要實現一個更清潔的分離。我的代碼是

的App.xaml：

<Application x:Class="NavigationCleanBinding.App" 
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
     StartupUri="/Views/MainWindowView.xaml"> 
    <Application.Resources> 
     <ResourceDictionary Source="MainResourceDictionary.xaml" /> 
    </Application.Resources> 
</Application> 

MainResourceDictionary.xaml：

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xamlpresentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:Views="clr-namespace:NavigationCleanBinding.Views" 
    xmlns:ViewModels="clr-namespace:NavigationCleanBinding.ViewModels"> 

    <DataTemplate DataType="{x:Type ViewModels:MainWindowViewModel}"> 
     <Views:MainWindowView /> 
    </DataTemplate> 

</ResourceDictionary> 

MainWindowView.xaml：

<Window x:Class="NavigationCleanBinding.Views.MainWindowView" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Title="MainWindow" Height="350" Width="525"> 

<Grid> 
    <TextBox Height="23" HorizontalAlignment="Left" Margin="61,14,0,0" 
      Name="textBox1" VerticalAlignment="Top" Width="120" 
      Text="{Binding TestData, Mode=TwoWay, 
      UpdateSourceTrigger=PropertyChanged}"/> 
    <Label Content="Test:" Height="28" HorizontalAlignment="Left" Margin="12,12,0,0" 
     Name="label1" VerticalAlignment="Top" Width="43" /> 
    <Label Content="Result:" Height="28" HorizontalAlignment="Left" Margin="10,46,0,0" 
     Name="label2" VerticalAlignment="Top" /> 

    <TextBox Height="23" HorizontalAlignment="Left" Margin="61,48,0,0" 
      Name="textBox2" VerticalAlignment="Top" Width="120" 

      Text="{Binding TestData, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"/> 
    </Grid> 
</Window> 

MainWindowViewModel：

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

namespace NavigationCleanBinding.ViewModels 
{ 
    class MainWindowViewModel 
    { 
     private String _testData; 
     public String TestData 
     { 
      get { return _testData; } 
      set { _testData = value; } 
     } 

     private MainWindowViewModel() 
     { 
      _testData = null; 
     } 
    } 
} 

UPDATE：

我改變屬性TESTDATA這樣：

public String TestData 
    { 
     get { return _testData; } 
     set 
     { 
      _testData = value; 
      OnPropertyChanged("TestData"); 

     } 
    } 

而且implemened的INotifyPropertyChanged的是這樣的：

public event PropertyChangedEventHandler PropertyChanged; 
    private void OnPropertyChanged(String propertyName) 
    { 
     PropertyChangedEventHandler handler = PropertyChanged; 
     if (handler != null) 
     { 
      handler(this, new PropertyChangedEventArgs(propertyName)); 
     } 
    } 

Answer 1

所以user1064 519是在正確的軌道上：

• 查看需要一個UserControl，而不是一個Window，因爲它是在主窗口

• 視圖模型需要被加載到主窗口託管，這是什麼觸發要發現並加載DataTemplate。

  <Window x:Class="WpfTemplateBootstrap.MainWindow" 
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
      xmlns:local="clr-namespace:WpfTemplateBootstrap" 
      Title="MainWindow" Height="350" Width="525"> 
      <ContentControl> 
       <ContentControl.Content> 
        <local:MainWindowViewModel /> 
       </ContentControl.Content> 
      </ContentControl> 
  

之後，你應該是啓動和運行。 我已經在這裏發佈了一個深入的示例：wpf bootstrapping datatemplates--the chicken and the egg

Answer 2

您的視圖模型必須實現的接口INotifyPropertyChanged並提出一個PropertyChanged事件時任何綁定的屬性值都會更改，以便您的視圖可以知道發生的更改。

Answer 3

DataTemplate sholudnt包含窗口，它可以包含任何類型的控件。

的DataTemplate：

<DataTemplate DataType="{x:Type ViewModels:MainWindowViewModel}"> 
     <Views:MainWindowView /> 
</DataTemplate> 

用戶控件：

<UserControl x:Class="NavigationCleanBinding.Views.MainView" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Height="350" Width="525"> 

<Grid> 
    <TextBox Height="23" HorizontalAlignment="Left" Margin="61,14,0,0" 
      Name="textBox1" VerticalAlignment="Top" Width="120" 
      Text="{Binding TestData, Mode=TwoWay, 
      UpdateSourceTrigger=PropertyChanged}"/> 
    <Label Content="Test:" Height="28" HorizontalAlignment="Left" Margin="12,12,0,0" 
     Name="label1" VerticalAlignment="Top" Width="43" /> 
    <Label Content="Result:" Height="28" HorizontalAlignment="Left" Margin="10,46,0,0" 
     Name="label2" VerticalAlignment="Top" /> 

    <TextBox Height="23" HorizontalAlignment="Left" Margin="61,48,0,0" 
      Name="textBox2" VerticalAlignment="Top" Width="120" 

      Text="{Binding TestData, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"/> 
    </Grid> 
</UserControl> 

窗口：

<Window x:Class="NavigationCleanBinding.Views.MainWindowView" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Title="MainWindow" Height="350" Width="525"> 

<ContentControl Content={Binding}/> 
</Window>