我喜欢MVVM Light框架，正如许多人所说，简单而强大。
我正在尝试禁用一个按钮，与EventToCommand示例相同（工作正常，但有针对性或3.5）。我添加了一个IsEnabled事件，正在解雇。
我的程序针对4.0。
我的命令已被禁用，但按钮保持启用状态。
我在我的程序中也添加了一个事件，但是没有触发。
不知道我错过了什么。
我的Xaml：
<Window x:Class="MyWPFApp.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WPF4"
xmlns:vw="clr-namespace:MyWPFApp.Views"
Title="MainWindow"
Height="300"
Width="300"
SizeToContent="WidthAndHeight"
DataContext="{Binding Source={StaticResource Locator}, Path=v_MainWindow}">
<Window.Resources>
<!--<ResourceDictionary x:Key="ResDict">
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="/Skins/MainSkin.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>-->
<ControlTemplate x:Key="ButtonTemplate"
TargetType="Button">
<Grid x:Name="Root"
Opacity="0.8"
RenderTransformOrigin="0.5,0.5">
<Grid.RenderTransform>
<TransformGroup>
<ScaleTransform />
<SkewTransform />
<RotateTransform />
<TranslateTransform />
</TransformGroup>
</Grid.RenderTransform>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition From="MouseOver"
GeneratedDuration="00:00:00.2000000"
To="Normal" />
<VisualTransition From="Normal"
GeneratedDuration="00:00:00.2000000"
To="MouseOver" />
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal" />
<VisualState x:Name="MouseOver">
<Storyboard>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Duration="00:00:00.0010000"
Storyboard.TargetName="Root"
Storyboard.TargetProperty="(UIElement.Opacity)">
<SplineDoubleKeyFrame KeyTime="00:00:00"
Value="1" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Duration="00:00:00.0010000"
Storyboard.TargetName="Root"
Storyboard.TargetProperty="(UIElement.Opacity)">
<SplineDoubleKeyFrame KeyTime="00:00:00"
Value="1" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Duration="00:00:00.0010000"
Storyboard.TargetName="Root"
Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<SplineDoubleKeyFrame KeyTime="00:00:00"
Value="0.9" />
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Duration="00:00:00.0010000"
Storyboard.TargetName="Root"
Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<SplineDoubleKeyFrame KeyTime="00:00:00"
Value="0.9" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Duration="00:00:00.0010000"
Storyboard.TargetName="Root"
Storyboard.TargetProperty="(UIElement.Opacity)">
<SplineDoubleKeyFrame KeyTime="00:00:00"
Value="0.4" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Rectangle Fill="{TemplateBinding Background}"
Stroke="Black"
RadiusX="8"
RadiusY="8" />
<TextBlock HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="{TemplateBinding Content}"
TextWrapping="Wrap"
FontSize="12"
FontWeight="Bold" />
</Grid>
</ControlTemplate>
<Style x:Key="ButtonStyle"
TargetType="Button">
<Setter Property="Template"
Value="{StaticResource ButtonTemplate}" />
<Setter Property="Cursor"
Value="Hand" />
</Style>
</Window.Resources>
<Grid x:Name="LayoutRoot">
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<StackPanel Grid.Row="0" Grid.Column="0" Orientation="Vertical" HorizontalAlignment="Left">
<Button Content="Change to Error Status" Style="{StaticResource ButtonStyle}" IsEnabledChanged="EnableChanged">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Click">
<cmd:EventToCommand Command="{Binding StatusCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource AncestorType=Button}, Path=Content}" MustToggleIsEnabled="True"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Button>
<Button Content="Change to Warning" Style="{StaticResource ButtonStyle}" IsEnabledChanged="EnableChanged">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Click">
<cmd:EventToCommand Command="{Binding StatusCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource AncestorType=Button}, Path=Content}" MustToggleIsEnabled="True"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Button>
<Button Content="Success" IsEnabled="False"/>
<Button Content="Info"/>
</StackPanel>
<TextBlock Grid.Row="0" Grid.Column="1"
FontSize="36"
FontWeight="Bold"
Foreground="Purple"
Text="{Binding Welcome}"
VerticalAlignment="Center"
HorizontalAlignment="Center"
TextWrapping="Wrap">
<!--<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseEnter">
<cmd:EventToCommand Command="{Binding StatusCommand}"
CommandParameter="Error" />
</i:EventTrigger>
</i:Interaction.Triggers>-->
</TextBlock>
<vw:v_StatusBar Grid.Row="1" Grid.ColumnSpan="2" />
</Grid>
viewmodel中的MY代码
using System.Windows;
using GalaSoft.MvvmLight;
using GalaSoft.MvvmLight.Command;
using GalaSoft.MvvmLight.Messaging;
namespace MyWPFApp.ViewModel
{
/// <summary>
/// This class contains properties that the main View can data bind to.
/// <para>
/// Use the <strong>mvvminpc</strong> snippet to add bindable properties to this ViewModel.
/// </para>
/// <para>
/// You can also use Blend to data bind with the tool's support.
/// </para>
/// <para>
/// See http://www.galasoft.ch/mvvm/getstarted
/// </para>
/// </summary>
public class vm_MainWindow : ViewModelBase
{
public string Welcome
{
get
{
return "Welcome to Geert's WPF template (based on MVVM Light)";
}
}
private string _status = "Initialized...";
public string Status
{
get
{
return _status;
}
private set
{
if (_status == value)
{
MessageBox.Show("Status is already " + value);
return;
}
_status = value;
MessageBox.Show("Setting status to " + _status);
Messenger.Default.Send<string>(value, "StatusChange");
}
}
public RelayCommand<string> StatusCommand
{
get;
private set;
}
/// <summary>
/// Initializes a new instance of the MainViewModel class.
/// </summary>
public vm_MainWindow()
{
if (IsInDesignMode)
{
// Code runs in Blend --> create design time data.
}
else
{
// Code runs "for real"
StatusCommand = new RelayCommand<string>(p => Status = string.Format("{0}", p), p => p != _status);
}
}
////public override void Cleanup()
////{
//// // Clean up if needed
//// base.Cleanup();
////}
}
}
答案 0 :(得分：0)
发现问题，CanExecuteChanged简单永不解雇!!!!!!
首先，我在（在relaycommand中）添加了以下备注中的建议： http://msdn.microsoft.com/query/dev10.query?appId=Dev10IDEF1&l=EN-US&k=k(SYSTEM.WINDOWS.INPUT.COMMANDMANAGER.REQUERYSUGGESTED);k(TargetFrameworkMoniker-%22.NETFRAMEWORK%2cVERSION%3dV4.0%22);k(DevLang-CSHARP)&rd=true
然后我注意到只有最后一个按钮被启用/禁用。
再次合乎逻辑，在relaycommand中添加的每个处理程序都覆盖了前一个处理程序。
所以，我在eventtocommand中添加了事件处理支持。
并且，一切都很好。
将把我的更正发送给Buignon先生，希望他能正式检查和发布。
ps只检查并更改为WPF 4.0（我现在只需要）