我有以下类(class):
public class LooklessControl : Control
{
public List<int> IntList { get; private set; }
public int CurrentInt { get; private set; }
private int _index = 0;
static LooklessControl()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(LooklessControl), new FrameworkPropertyMetadata(typeof(LooklessControl)));
}
public LooklessControl()
{
IntList = new List<int>();
for (int i = 0; i < 10; i++)
{
IntList.Add(i);
}
CurrentInt = IntList[_index];
}
public static readonly RoutedCommand NextItemCommand =
new RoutedCommand("NextItemCommand", typeof(LooklessControl));
private void ExecutedNextItemCommand(object sender, ExecutedRoutedEventArgs e)
{
NextItemHandler();
}
private void CanExecuteNextItemCommand(object sender, CanExecuteRoutedEventArgs e)
{
e.CanExecute = true;
}
public static readonly RoutedCommand PrevItemCommand =
new RoutedCommand("PrevItemCommand", typeof(LooklessControl));
private void ExecutedPrevItemCommand(ExecutedRoutedEventArgs e)
{
PrevItemHandler();
}
private void CanExecutePrevItemCommand(object sender, CanExecuteRoutedEventArgs e)
{
e.CanExecute = true;
}
public static readonly RoutedEvent NextItemEvent =
EventManager.RegisterRoutedEvent("NextItemEvent", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(LooklessControl));
public event RoutedEventHandler NextItem
{
add { AddHandler(NextItemEvent, value); }
remove { RemoveHandler(NextItemEvent, value); }
}
private void RaiseNextItemEvent()
{
RoutedEventArgs args = new RoutedEventArgs(LooklessControl.NextItemEvent);
RaiseEvent(args);
}
public static readonly RoutedEvent PrevItemEvent =
EventManager.RegisterRoutedEvent("PrevItemEvent", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(LooklessControl));
public event RoutedEventHandler PrevItem
{
add { AddHandler(PrevItemEvent, value); }
remove { RemoveHandler(PrevItemEvent, value); }
}
private void RaisePrevItemEvent()
{
RoutedEventArgs args = new RoutedEventArgs(LooklessControl.PrevItemEvent);
RaiseEvent(args);
}
private void NextItemHandler()
{
_index++;
if (_index == IntList.Count)
{
_index = 0;
}
CurrentInt = IntList[_index];
RaiseNextItemEvent();
}
private void PrevItemHandler()
{
_index--;
if (_index == 0)
{
_index = IntList.Count - 1;
}
CurrentInt = IntList[_index];
RaisePrevItemEvent();
}
}
该类在 Generic.xaml 中具有默认样式，如下所示:
<Style x:Key="{x:Type local:LooklessControl}" TargetType="{x:Type local:LooklessControl}">
<Setter Property="Height" Value="200"/>
<Setter Property="Width" Value="90"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:LooklessControl}">
<Border BorderBrush="Black" BorderThickness="1" Padding="2">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="20"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Rectangle Grid.Row="0" Fill="LightGray"/>
<Rectangle Grid.Row="1" Fill="Gainsboro"/>
<Grid Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="10"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="10"/>
</Grid.ColumnDefinitions>
<Path Grid.Column="0" x:Name="pathLeftArrow" Data="M0,0.5 L1,1 1,0Z" Width="6" Height="14" Stretch="Fill"
HorizontalAlignment="Center" Fill="SlateBlue"/>
<TextBlock Grid.Column="1" Name="textBlock"
Text="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=CurrentInt}"
HorizontalAlignment="Center" VerticalAlignment="Center" FontFamily="Junction" FontSize="13"/>
<Path Grid.Column="2" x:Name="pathRightArrow" Data="M0,0 L1,0.5 0,1Z" Width="6" Height="14" Stretch="Fill"
HorizontalAlignment="Center" Fill="SlateBlue"/>
</Grid>
<ListBox Grid.Row="1" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" Background="Transparent"
ItemsSource="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=IntList}"/>
</Grid>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
如何做到这样，当用户单击 pathLeftArrow 时，它会触发 LooklessControl.PrevItemCommand，或者他们单击 pathRightArrow 时，它会触发 LooklessControl.NextItemCommand，或者他们单击 ListBox 中的某个项目，并且 LooklessControl 会收到通知新选择的项目？
换句话说，如果不将 x:Class 添加到 Generic.xaml 的顶部并为其创建一个代码隐藏文件(我假设您不想这样做)，那么如何处理您的元素中的事件没有 Command 属性的 xaml(它几乎是除 Button 之外的所有属性)？
LooklessControl 是否应该拥有与其关联的自己的 XAML 文件(很像您在创建新 UserControl 时获得的文件)，而 Generic.xaml 仅将其作为 MergedDictionar 作为其默认模板引入？或者还有其他公认的方法来做我想做的事情吗？
最佳答案
回答你的最后一个问题:不。外观控件不需要任何已知的 XAML。这就是“lookless”的意思。
这里有几个选项，但我建议使用基本上空的控件模板将元素包装在按钮中:
<ControlTemplate x:Key="contentOnlyButton" TargetType="{x:Type Button}">
<ContentPresenter />
</ControlTemplate>
...
<Button Grid.Column="0" Template="{StaticResource contentOnlyButton}"
Command="{x:Static local:LooklessControl.PrevItemCommand}">
<Path x:Name="pathLeftArrow" Data="M0,0.5 L1,1 1,0Z" Width="6" Height="14"
Stretch="Fill" HorizontalAlignment="Center" Fill="SlateBlue"/>
</Button>
您的另一个选择(我想说这可能不是您在单击时执行命令应该做的事情，但可能适用于其他情况)，是在 OnApplyTemplate 中查找模板中的指定部分，然后连线上事件。
public override void OnApplyTemplate()
{
var prevElement = this.GetTemplateChild("PART_PathLeftArrow") as UIElement;
if (prevElement != null)
prevElement.MouseDown += (o, e) => PrevItemHandler();
...
}
执行此操作时需要注意的一件事是，模板不需要定义您正在查找的部分，因此您需要优雅地检查该情况。对于意外删除所需元素的设计人员/开发人员来说，在此处抛出 NullReferenceExceptions 将使重新设计控件变得非常痛苦。您还需要遵循使用 PART_ 语法命名所需元素的标准做法，并使用 TemplatePart 属性装饰您的类。
[TemplatePart(Name = "PART_PathLeftArrow", Type = typeof(UIElement))]
[TemplatePart(Name = "PART_PathRightArrow", Type = typeof(UIElement))]
...
public class LooklessControl : Control
编辑:为了使按钮响应点击，您需要将 CommandBindings 设置为您已定义的函数。您可以将其作为类命令绑定(bind)来执行，如下所示:
static LooklessControl()
{
CommandManager.RegisterClassCommandBinding(
typeof(LooklessControl),
new CommandBinding(NextItemCommand, ExecutedNextItemCommand, CanExecuteNextItemCommand));
CommandManager.RegisterClassCommandBinding(
typeof(LooklessControl),
new CommandBinding(PrevItemCommand, ExecutedPrevItemCommand, CanExecutePrevItemCommand));
}
进行类命令绑定(bind)的原因是，如果将其添加到控件的 CommandBindings 集合中，使用您的控件的人可能会无意中删除它们。另请记住更新您的命令处理方法以具有静态语义。
关于c# - WPF Lookless 控制事件，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/2548116/