WPF在ViewModel.PropertyChanged事件上更改Button Content
我的尝试（下面）失败了：
＆lt; Canvas x：Key =“Lock”... /＆gt;
＆lt; Canvas x：Key =“Unlock”... /＆gt;
＆lt; Style x：Key =“LockButtonStyle”TargetType =“{x：Type Button}”＆gt;
＆LT; Style.Triggers＆GT;
＆lt; DataTrigger Binding =“{Binding Path = IsReadOnly}”Value =“True”＆gt;
＆LT; DataTrigger.Setters＆GT;
＆lt; Setter Property =“Content”Value =“{StaticResource Lock}”/＆gt;
＆LT; /DataTrigger.Setters>
＆LT; / DataTrigger＆GT;
＆lt; DataTrigger Binding =“{Binding Path = IsReadOnly}”Value =“False”＆gt;
＆LT; DataTrigger.Setters＆GT;
＆lt; Setter Property =“Content”Value =“{StaticResource Unlock}”/＆gt;
＆LT; /DataTrigger.Setters>
＆LT; / DataTrigger＆GT;
＆LT; /Style.Triggers>
＆LT; /样式>
...
＆lt; Button Content =“{StaticResource Lock}”/＆gt;
当ViewModel上的IsReadOnly属性发生更改时，我试图让按钮更改（它使用“IsReadOnly”作为PropertyName触发INotifyPropertyChanged.PropertyChanged）。我错过了什么？
.NET 3.5
答案（至少对我而言 - 不支持一般情况）：
我刚刚为布尔属性绑定编写了一个快速转换器。
[ValueConversion（typeof（bool），typeof（object））]
public class BooleanValueConverter：IValueConverter
{
公共对象FalseValue {get;组; }
公共对象TrueValue {get;组; }
#region IValueConverter成员
public object Convert（对象值，类型targetType，
对象参数，CultureInfo文化）
{
return（bool）值？ this.TrueValue：this.FalseValue;
}
公共对象ConvertBack（对象值，类型targetType，
对象参数，CultureInfo文化）
{
return object.Equals（this.TrueValue，value）？真假;
}
#endregion
}
...
＆lt; local：BooleanValueConverter x：Key =“LockOrUnlock”
TrueValue =“{StaticResource Unlock}”
FalseValue =“{StaticResource Lock}”/＆gt;
...
＆lt; Button Content =“{Binding Path = IsReadOnly，
Converter = {StaticResource LockOrUnlock}}“/＆gt;
没有找到相关结果
已邀请:
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<Window.Resources> <local:ViewModel x:Key="TheViewModel" /> <Canvas x:Key="Lock"> <TextBlock Text="Lock"/> </Canvas> <Canvas x:Key="Unlock"> <TextBlock Text="Unlock"/> </Canvas> <Style x:Key="LockButtonStyle" TargetType="{x:Type Button}"> <Style.Triggers> <DataTrigger Binding="{Binding Path=IsReadOnly}" Value="true"> <DataTrigger.Setters> <Setter Property="Content" Value="{StaticResource Lock}" /> </DataTrigger.Setters> </DataTrigger> <DataTrigger Binding="{Binding Path=IsReadOnly}" Value="false"> <DataTrigger.Setters> <Setter Property="Content" Value="{StaticResource Unlock}" /> </DataTrigger.Setters> </DataTrigger> </Style.Triggers> </Style> </Window.Resources> <Grid DataContext="{StaticResource TheViewModel}"> <Grid.RowDefinitions> <RowDefinition Height="auto"/> <RowDefinition Height="auto"/> </Grid.RowDefinitions> <Button x:Name="LockButton" Style="{StaticResource LockButtonStyle}" /> <Button x:Name="ChangeIsReadOnly" Content="Change State" Grid.Row="1" Click="ChangeIsReadOnly_Click"/> </Grid>public MainWindow() { InitializeComponent(); } private void ChangeIsReadOnly_Click(object sender, RoutedEventArgs e) { ViewModel theViewModel = (ViewModel)FindResource("TheViewModel"); theViewModel.IsReadOnly = !theViewModel.IsReadOnly; }public class ViewModel : System.ComponentModel.INotifyPropertyChanged { public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged; private bool isReadOnly; public bool IsReadOnly { get { return isReadOnly; } set { isReadOnly = value; PropertyChanged(this, new System.ComponentModel.PropertyChangedEventArgs("IsReadOnly")); } } }