在wpf中不斷改變按鈕的背景

Question

我的窗戶上有一個按鈕。 默認情況下，按鈕的背景色為藍色。 單擊按鈕后，顏色應更改為紅色。 但我看到背景顏色正在變為紅色，但不是永久的。

這是課程代碼：

/// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window, INotifyPropertyChanged
    {
        bool _highLow;
        public MainWindow()
        {
            InitializeComponent();
            this.DataContext = this;
           _highLow = false;

        }

        public bool RiskHighLowMedium
        {
            get { return _highLow; }
            set { _highLow= value ;

            this.OnPropertyChanged("RiskHighLowMedium");
            this.OnPropertyChanged("BackGround");
            }
        }


         //background Dependency Property
        public static readonly DependencyProperty BackgroundProperty;


        /// <summary>
        /// static constructor
        /// </summary>
        static MainWindow()
        {
            BackgroundProperty = DependencyProperty.Register("Background", typeof(Brush), typeof(MainWindow));
        }


        /// <summary>
        /// Background Dependency
        /// Property
        /// </summary>
        public Brush Background
        {
            get { return (Brush)GetValue(BackgroundProperty); }
            set { SetValue(BackgroundProperty, value); }

        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            RiskHighLowMedium = true;
            Background = RiskHighLowMedium ? Brushes.Red : Brushes.Blue;
            this.OnPropertyChanged("RiskHighLowMedium");
            this.OnPropertyChanged("Background");
        }




        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void OnPropertyChanged(string propertyName)
        {

            if (this.PropertyChanged != null)
                this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }

        #endregion // INotifyPropertyChanged Members
    }

XAML代碼：

<Window x:Class="backgrounChange.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">

    <Window.Resources>
    <Style x:Key="CircleButton" TargetType="Button">


            <Setter Property="Background" Value="Blue"/>

            <Style.Triggers>

            <DataTrigger Binding="{Binding RiskHighLowMedium }"  Value="true">
                    <Setter Property="Background" Value="{ Binding Path= Background}"/>
                </DataTrigger>


            </Style.Triggers>

    </Style>
    </Window.Resources>

    <Grid>
        <Button Width="50" Height="50" Style="{DynamicResource  CircleButton}" Click="Button_Click"/>
    </Grid>
</Window>

我會在這里提供任何幫助。

Answer 1

雖然可以更改Button.Background值，但是Button控件的默認ControlTemplate定義了一個動畫，該動畫在Button.Background官方值和另一種（淺藍色）顏色之間為Button的背景設置動畫。 要擺脫這種行為，您將必須為Button定義一個新的ControlTemplate 。 這是一個非常基本的示例：

<Style x:Key="CircleButton" TargetType="Button">
    <Setter Property="Background" Value="Blue"/>
    <Style.Triggers>
        <DataTrigger Binding="{Binding RiskHighLowMedium}" Value="True">
            <Setter Property="Button.Background" Value="Red" />
        </DataTrigger>
    </Style.Triggers>
</Style>

...

<Button Width="50" Height="50" Style="{StaticResource CircleButton}" 
    Click="Button_Click">
    <Button.Template>
        <ControlTemplate>
            <Border Background="{TemplateBinding Background}">
                <ContentPresenter />
            </Border>
        </ControlTemplate>
    </Button.Template>
</Button>

...

bool _highLow = false;
public bool RiskHighLowMedium
{
    get { return _highLow; }
    set { _highLow = value; OnPropertyChanged("RiskHighLowMedium"); }
}

...

private void Button_Click(object sender, RoutedEventArgs e)
{
    RiskHighLowMedium = true;
}