WPF-使用DataTrigger的按鈕樣式的動畫

Question

我正在開發C＃WPF應用程序，並嘗試旋轉按鈕或按鈕的內容以設置刷新狀態的動畫。 因此，我使用DataTrigger擴展了按鈕樣式，並綁定到ViewModel的屬性。 但是，當我啟動應用程序並更改屬性時，什么也沒有發生。 我錯過了什么？

下面是該按鈕的一些代碼片段：

<Button Style="{StaticResource MenuButtonStyle}"
        Command="{Binding RefreshCommand}">
    <Viewbox>
        <Path Data="M1.1212257,9.3630001L6.5977538,11.580556 4.2506914,12.856734C5.4929478,15.192778 7.9304001,16.795777 10.761055,16.795777 13.75407,16.795777 16.324983,15.014366 17.488389,12.45831L19.643999,12.45831C18.371294,16.144636 14.875176,18.804999 10.761055,18.804999 7.1745365,18.804999 4.0586705,16.782776 2.4753525,13.820294L0,15.164176z M10.760896,0C14.30653,1.3528629E-07,17.389073,1.977851,18.989344,4.8840143L21.333,3.5363943 20.353317,9.3630001 14.824021,7.2771222 17.239375,5.8891636C15.988099,3.5858327 13.567544,2.0091001 10.760896,2.0091001 7.7688711,2.0091001 5.1979985,3.7902967 4.0345705,6.3461806L1.879,6.3461806C3.1517664,2.6600806,6.6478317,1.3528629E-07,10.760896,0z"
              Stretch="Uniform" Fill="{StaticResource IconColor}"/>
    </Viewbox>
</Button>

以及ViewModel的屬性：

private bool _isRefreshing = false;
public bool IsRefreshing
{
    get { return _isRefreshing; }
    set
    {
        _isRefreshing = value;
        OnPropertyChanged("IsRefreshing");
    }
}

我的按鈕樣式如下：

<Style x:Key="MenuButtonStyle" TargetType="{x:Type Button}">
    <Setter Property="Background" Value="Transparent"/>
    <Setter Property="Margin" Value="5"/>
    <Setter Property="Padding" Value="5"/>
    <Setter Property="BorderThickness" Value="0"/>
    <Setter Property="Width" Value="32"/>
    <Setter Property="Height" Value="32"/>
    <Style.Triggers>
        <DataTrigger Binding="{Binding Path=IsRefreshing}" Value="true">
            <DataTrigger.EnterActions>
                <BeginStoryboard>
                    <Storyboard>
                        <DoubleAnimation Storyboard.TargetProperty="(LayoutTransform).(RotateTransform.Angle)"
                                         From="0"
                                         To="360"
                                         Duration="0:0:8"
                                         RepeatBehavior="Forever"
                                         />
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.EnterActions>
            <DataTrigger.ExitActions>
                <BeginStoryboard>
                    <Storyboard FillBehavior="Stop">
                        <DoubleAnimation Storyboard.TargetProperty="(LayoutTransform).(RotateTransform.Angle)"
                                         To="0"
                                         Duration="0:0:0"
                                         />
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.ExitActions>
        </DataTrigger>
    </Style.Triggers>
</Style>

Answer 1

假設DataContext的的Button相應設置，並先后獲得IsRefreshing財產，你不設置LayoutTransfom的的Button來RotateTransform所以沒有什么動畫。 另一個二傳手添加到您Style

<Setter Property="LayoutTransform">
    <Setter.Value>
        <RotateTransform Angle="0"/>
    </Setter.Value>
</Setter>