Question

我正在尝试创建用户控件，以允许用户在应用程序中定义自己的自定义线性渐变。

到目前为止，我有一个用户控件，它使用以下模型来定义渐变停止的集合：

public class StopSelectorModel : INotifyPropertyChanged {
    #region Field Values
    private Task _PropertyT;
    private ObservableCollection<GradientStop> _Stops;
    private GradientStop _SelectedStop;
    public event PropertyChangedEventHandler PropertyChanged;
    #endregion

    #region Properties
    /// <summary>
    /// Get or Set Gradient Stop Collection.
    /// </summary>
    public ObservableCollection<GradientStop> Stops {
        get { return this._Stops; }
        set {
            this._Stops = value;
            this._SelectedStop = value.FirstOrDefault( );

            this._PropertyT = Task.WhenAll( new Task[ ] {
                this.OnPropertyChanged( "Stops" ),
                this.OnPropertyChanged( "SelectedStop" )
            } );
        }
    }

    /// <summary>
    /// Get or Set Selected Gradient Stop.
    /// </summary>
    public GradientStop SelectedStop {
        get { return this._SelectedStop; }
        set {
            if ( value == null )
                return;

            if ( !this._Stops.Contains( value ) )
                this._Stops.Add( value );
            this._SelectedStop = value;

            this._PropertyT = this.OnPropertyChanged( "SelectedStop" );
        }
    }
    #endregion

    #region Methods
    protected async Task OnPropertyChanged( string P ) {
        if ( this.PropertyChanged != null )
            await this.PropertyChanged.Async( this, new PropertyChangedEventArgs( P ) );
    }
    #endregion

    #region Constructors
    /// <summary>
    /// Declare instance of StopSelectorModel.
    /// </summary>
    /// <param name="Base">GradientStopCollection to wrap.</param>
    public StopSelectorModel( ObservableCollection<GradientStop> Base ) { this.Stops = Base; }

    /// <summary>
    /// Declare default instance of StopSelectorModel.
    /// </summary>
    public StopSelectorModel( ) : this( new ObservableCollection<GradientStop>( new GradientStop[ ] {
        new GradientStop( Colors.White, 0.0D ),
        new GradientStop( Colors.Black, 1.0D )
    } ) ) { }
    #endregion
}

我将它用作ComboBox的DataContext（ItemSource = Stops，SelectedItem = SelectedStop，双向绑定，据我所知这样的标准操作程序）。

我还有一个控件，它使用以下颜色模型来定义颜色（基本上是4个滑动条）：

/// <summary>
/// Wrapper for allowing complete databinding of a System.Windows.Media.Color struct.
/// </summary>
public class ColorModel : INotifyPropertyChanged {
    private Task _PropertyT;
    private Color _Color;

    /// <summary>
    /// Get or Set Context Color.
    /// </summary>
    public Color Color {
        get { return this._Color; }
        set {
            this._Color = value;
            this._PropertyT = Task.WhenAll( new Task[ ] {
                this.OnPropertyChanged( "Color" ),
                this.OnPropertyChanged( "ScA" ),
                this.OnPropertyChanged( "ScR" ),
                this.OnPropertyChanged( "ScG" ),
                this.OnPropertyChanged( "ScB" ),
            } );
        }
    }

    /// <summary>
    /// Get or Set Color ScA value.
    /// </summary>
    public double ScA {
        get { return this._Color.ScA; }
        set {
            this._Color.ScA = ( float )value;
            this._PropertyT = Task.WhenAll( new Task[ ] {
                this.OnPropertyChanged( "Color" ),
                this.OnPropertyChanged( "ScA" ),
            } );
        }
    }

    /// <summary>
    /// Get or Set Color ScR value.
    /// </summary>
    public double ScR {
        get { return this._Color.ScR; }
        set {
            this._Color.ScR = ( float )value;
            this._PropertyT = Task.WhenAll( new Task[ ] {
                this.OnPropertyChanged( "Color" ),
                this.OnPropertyChanged( "ScR" ),
            } );
        }
    }

    /// <summary>
    /// Get or Set Color ScG value.
    /// </summary>
    public double ScG {
        get { return this._Color.ScG; }
        set {
            this._Color.ScG = ( float )value;
            this._PropertyT = Task.WhenAll( new Task[ ] {
                this.OnPropertyChanged( "Color" ),
                this.OnPropertyChanged( "ScG" ),
            } );
        }
    }

    /// <summary>
    /// Get or Set Color ScB value.
    /// </summary>
    public double ScB {
        get { return this._Color.ScB; }
        set {
            this._Color.ScB = ( float )value;
            this._PropertyT = Task.WhenAll( new Task[ ] {
                this.OnPropertyChanged( "Color" ),
                this.OnPropertyChanged( "ScB" ),
            } );
        }
    }

    protected async Task OnPropertyChanged( string P ) {
        await this.PropertyChanged?.Async(
            this, new PropertyChangedEventArgs( P ) ).DontBlock( );
    }
    public event PropertyChangedEventHandler PropertyChanged;

    /// <summary>
    /// Define ColorModel with default White Color.
    /// </summary>
    public ColorModel( ) : this( Colors.White ) { }

    /// <summary>
    /// Define ColorModel with provided color.
    /// </summary>
    /// <param name="C">Color to assign to ColorModel.</param>
    public ColorModel( Color C ) { this.Color = C; }
}

所以我们在这里...如何将我的ComboBox的SelectedItem的Color属性与此ColorModel绑定在一起？（如果/必要时会提供更多详细信息，但时间会很短。）

提前感谢您的帮助......

编辑1

为了清楚起见 - 我想将SelectedValue（Color）传递给一个能够编辑该颜色的控件。

因此，操作的顺序是让ComboBox选择一个渐变停止，然后（这是我需要帮助的地方）控件，它负责调整颜色值。

Answer 1

如果我理解你，你想要在选择项目时选择渐变色。

我会为它创建自己的DataTemplate，并将颜色设置为GradientStop中运行时构建颜色的绑定。根据您是否希望所有组合框项目都有颜色，这可能会有所帮助：Can I use a different Template for the selected item in a WPF ComboBox than for the items in the dropdown part?

修改

作为对编辑的回应：如果我理解正确你有UserControl与DataContext是一些UserControlModel，其中的儿童是StopSelectorModel，在这种情况下我会选择提高事件在SelectedGradientStop设置并在UserControlModel中处理此事件

或者，如果它不是子 - 父关系，我会使用Messanger并在设置SelectedGradientStop时发送消息。

事件和消息都必须包含描述应该使用什么颜色的对象。

如何从ComboBox的Selected Item绑定到属性？

编辑1

1 个答案: