我拥有的是一个具有IsReadOnly属性的对象。如果此属性为true，我想将按钮上的IsEnabled属性设置为false(例如)。
我愿意相信我可以像IsEnabled="{绑定路径=!IsReadOnly}”，但这与WPF不兼容。
我是否不得不经历所有的样式设置?对于将一个bool值设置为另一个bool值的倒数这样简单的事情来说，似乎太啰嗦了。
<Button.Style>
<Style TargetType="{x:Type Button}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=IsReadOnly}" Value="True">
<Setter Property="IsEnabled" Value="False" />
</DataTrigger>
<DataTrigger Binding="{Binding Path=IsReadOnly}" Value="False">
<Setter Property="IsEnabled" Value="True" />
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
I did something very similar. I created my property behind the scenes that enabled the selection of a combobox ONLY if it had finished searching for data. When my window first appears, it launches an async loaded command but I do not want the user to click on the combobox while it is still loading data (would be empty, then would be populated). So by default the property is false so I return the inverse in the getter. Then when I'm searching I set the property to true and back to false when complete.
private bool _isSearching;
public bool IsSearching
{
get { return !_isSearching; }
set
{
if(_isSearching != value)
{
_isSearching = value;
OnPropertyChanged("IsSearching");
}
}
}
public CityViewModel()
{
LoadedCommand = new DelegateCommandAsync(LoadCity, LoadCanExecute);
}
private async Task LoadCity(object pArg)
{
IsSearching = true;
//**Do your searching task here**
IsSearching = false;
}
private bool LoadCanExecute(object pArg)
{
return IsSearching;
}
然后，对于组合框，我可以直接绑定到IsSearching:
<ComboBox ItemsSource="{Binding Cities}" IsEnabled="{Binding IsSearching}" DisplayMemberPath="City" />
对于标准绑定，您需要使用看起来有点风的转换器。所以，我建议你看看我的CalcBinding项目，它是专门解决这个问题和其他一些问题而开发的。使用高级绑定，您可以直接在xaml中编写带有许多源属性的表达式。比如，你可以这样写:
<Button IsEnabled="{c:Binding Path=!IsReadOnly}" />
or
<Button Content="{c:Binding ElementName=grid, Path=ActualWidth+Height}"/>
or
<Label Content="{c:Binding A+B+C }" />
or
<Button Visibility="{c:Binding IsChecked, FalseToVisibility=Hidden}" />
其中A, B, C, IsChecked - viewModel的属性，它将正常工作
I did something very similar. I created my property behind the scenes that enabled the selection of a combobox ONLY if it had finished searching for data. When my window first appears, it launches an async loaded command but I do not want the user to click on the combobox while it is still loading data (would be empty, then would be populated). So by default the property is false so I return the inverse in the getter. Then when I'm searching I set the property to true and back to false when complete.
private bool _isSearching;
public bool IsSearching
{
get { return !_isSearching; }
set
{
if(_isSearching != value)
{
_isSearching = value;
OnPropertyChanged("IsSearching");
}
}
}
public CityViewModel()
{
LoadedCommand = new DelegateCommandAsync(LoadCity, LoadCanExecute);
}
private async Task LoadCity(object pArg)
{
IsSearching = true;
//**Do your searching task here**
IsSearching = false;
}
private bool LoadCanExecute(object pArg)
{
return IsSearching;
}
然后，对于组合框，我可以直接绑定到IsSearching:
<ComboBox ItemsSource="{Binding Cities}" IsEnabled="{Binding IsSearching}" DisplayMemberPath="City" />
