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并不是StackPanel的所有datatrigger都在工作

stackpanel datatrigger storyboard background wpf

0

Phil · 技术社区 · 7 年前

我有一个显示文本和图像的按钮:

当变量“ActiveState”改变时,StackPanel的背景也应该改变,为此我使用DataTriggers

活动状态=0->红色/ 活动状态=1->蓝色/ 活动状态=2->蓝色闪烁(为此,我使用故事板和彩色动画)

当我移除Stackpanel(Background=“Transparent”)的背景时,前两个触发器正在工作,但最后一个触发器会出现以下异常:

PresentationFramework.dll中发生类型为“System.InvalidOperationException”的未处理异常

其他信息:后台属性未指向路径(0)中的dependencyobject。(1)

这是我的密码:

<Button>
  <Button.Template>
    <ControlTemplate TargetType="Button">
        <StackPanel Orientation="Horizontal" Name="SelectButtonStackpanel" Background="Transparent">
            <TextBlock Text="{Binding Text}"/>
            <Image Source="{Binding Image}" Stretch="Uniform" Height="40" Width="40"/>                    
                <StackPanel.Style>
                    <Style TargetType="{x:Type StackPanel}">
                        <Style.Triggers>

                            <DataTrigger Binding="{Binding ActiveState}" Value="0">
                                <Setter Property="Background" Value="Red"/>
                            </DataTrigger>

                            <DataTrigger Binding="{Binding ActiveState}" Value="1">
                                <Setter Property="Background" Value="Blue"/>
                            </DataTrigger>

                            <DataTrigger Binding="{Binding ActiveState}" Value="2">
                                <DataTrigger.EnterActions>
                                    <BeginStoryboard>
                                        <Storyboard>
                                            <ColorAnimation 
                                                Storyboard.TargetProperty="(StackPanel.Background).(SolidColorBrush.Color)"
                                                To="Blue" Duration="0:0:1" AutoReverse="True" RepeatBehavior="Forever"
                                                >
                                            </ColorAnimation>
                                        </Storyboard>
                                    </BeginStoryboard>
                                </DataTrigger.EnterActions>

                                <DataTrigger.ExitActions>
                                    <BeginStoryboard>
                                        <Storyboard>
                                            <ColorAnimation 
                                                Storyboard.TargetProperty="(StackPanel.Background).(SolidColorBrush.Color)"
                                                Duration="0:0:1"
                                                >
                                            </ColorAnimation>
                                        </Storyboard>
                                    </BeginStoryboard>
                                </DataTrigger.ExitActions>
                            </DataTrigger>

                        </Style.Triggers>
                    </Style>
                </StackPanel.Style>
            </StackPanel>
    </ControlTemplate>
  </Button.Template>
</Button>

致以最诚挚的问候菲尔

1 回复 | 直到 7 年前

1

Clemens 7 年前

当你直接设置 Background="Transparent" 在StackPanel上,它具有更高的 precedence

除此之外,如果你想制作动画 Background.Color 您应该始终明确指定SolidColorBrushes,而不是预定义的笔刷,如 Background="Red" .

<StackPanel Orientation="Horizontal" Name="SelectButtonStackpanel">
    <StackPanel.Style>
        <Style TargetType="StackPanel">
            <Setter Property="Background">
                <Setter.Value>
                    <SolidColorBrush Color="Transparent"/>
                </Setter.Value>
            </Setter>
            <Style.Triggers>
                <DataTrigger Binding="{Binding ActiveState}" Value="0">
                    <Setter Property="Background">
                        <Setter.Value>
                            <SolidColorBrush Color="Red"/>
                        </Setter.Value>
                    </Setter>
                </DataTrigger>
                <DataTrigger Binding="{Binding ActiveState}" Value="1">
                    <Setter Property="Background">
                        <Setter.Value>
                            <SolidColorBrush Color="Blue"/>
                        </Setter.Value>
                    </Setter>
                </DataTrigger>
                <DataTrigger Binding="{Binding ActiveState}" Value="2">
                    <DataTrigger.EnterActions>
                        <BeginStoryboard>
                            <Storyboard>
                                <ColorAnimation 
                                    Storyboard.TargetProperty="Background.Color"
                                    To="Blue" Duration="0:0:1"
                                    AutoReverse="True" RepeatBehavior="Forever">
                                </ColorAnimation>
                            </Storyboard>
                        </BeginStoryboard>
                    </DataTrigger.EnterActions>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </StackPanel.Style>
</StackPanel>