通过

演练：在控件内部实现一个轨道

  • 项目

[本文档仅供预览，在以后的发行版中可能会发生更改。包含的空白主题用作占位符。]

本演练演示如何创建 windows presentation foundation (WPF) 自定义控件创建轨道装饰器。 轨道装饰器添加一个标记或标尺沿是不可缩放沿单个轴控件一侧。 装饰器是一个滑块，在控件中放置。 可以使用该装饰器设置在自定义按钮控件上 RenderTransform 属性。 设置 RenderTransform 属性偏移量控件。 有关完整的代码清单，请参见从站点的扭曲装饰器 WPF 设计器扩展性示例 示例。 .

在本演练中，您将执行下列任务:

  • 创建一个 WPF 自定义控件库项目。

  • 创建设计时元数据的一个单独的程序集。

  • 实现装饰器提供程序。

  • 在设计时测试控件。

完成后，您将知道如何为自定义控件创建装饰器。

备注

您看到的对话框和菜单命令可能会与 " 帮助 " 中的描述不同具体取决于您现用的设置或版本。若要更改设置，请选择在 工具 菜单的 导入和导出设置 。有关更多信息，请参见 Visual Studio 设置。

系统必备

您需要以下组件来完成本演练:

  • Visual Studio 2012 RC.

创建自定义控件

第一步是为自定义控件创建项目。 该控件是带有少量设计时代码的一个简单的按钮，使用 GetIsInDesignMode 方法实现设计时行为。

创建自定义控件

  1. 创建新 WPF 自定义控件库名为 SkewButtonLibrary的项目在 Visual Basic 或 Visual C#。

    CustomControl1 的代码在代码编辑器中打开。

  2. 在 解决方案资源管理器，将代码文件的名称改为 SkewButton.cs 或 SkewButton.vb。 如果此项目请求的出现消息框是要执行重命名所有引用，单击 是。

  3. 打开 SkewButton.cs 或 SkewButton.vb 在代码编辑器中。

  4. 用下面的代码替换自动生成的代码。 ，当按钮出现在设计器中时， SkewButton 自定义控件从 Button 继承并显示文本 “已激活设计模式”。 GetIsInDesignMode 检查和下面的设计时代码可选和仅演示。

    Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.ComponentModel


' The SkewButton control implements a button
' with a skew transformation applied.
Public Class SkewButton
    Inherits Button

    Public Sub New() 

        ' The following code enables custom design-mode logic.
        ' The GetIsInDesignMode check and the following design-time 
        ' code are optional and shown only for demonstration.
        If DesignerProperties.GetIsInDesignMode(Me) Then
            Content = "Design mode active"
        End If

    End Sub
End Class

    using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;
using System.Windows.Media;
using System.ComponentModel;

namespace SkewButtonLibrary
{
    // The SkewButton control implements a button
    // with a skew transformation applied.
    public class SkewButton : Button
    {
        public SkewButton()
        {   
            // The following code enables custom design-mode logic.
            // The GetIsInDesignMode check and the following design-time 
            // code are optional and shown only for demonstration.
            if (DesignerProperties.GetIsInDesignMode(this))
            {
                Content = "Design mode active";
            }
        }
    }
}

  5. 将项目的输出路径设置为 “bin \”。

  6. 生成解决方案。

创建设计时元数据程序集

设计时代码在特定元数据程序集中部署。 对于本演练，自定义装饰器在名为 SkewButtonLibrary.VisualStudio.Design 的程序集中部署。 有关更多信息，请参见 提供设计时元数据。

创建设计时元数据程序集

  1. 在 Visual Basic 中添加个新的类库名为 SkewButtonLibrary.VisualStudio.Design 的项目或 Visual c# 为解决方案。

  2. 将项目的输出路径设置为 “ \ SkewButtonLibrary \ bin \”。 这在同一文件夹使控件的程序集和元数据程序集，使设计器的元数据发现。

  3. 添加对下列 WPF 程序集。

    • PresentationCore

    • PresentationFramework

    • System.Xaml

    • WindowsBase

  4. 添加对以下 WPF Designer 程序集。

    • Microsoft.Windows.Design.Extensibility

    • Microsoft.Windows.Design.Interaction

  5. 添加对 SkewButtonLibrary 项目。

  6. 在 解决方案资源管理器，将 Class1 代码文件的名称改为 Metadata.cs 或 Metadata.vb。 如果此项目请求的出现消息框是要执行重命名所有引用，单击 是。

  7. 用下面的代码替换自动生成的代码。 将自定义设计时实现附加到 SkewButton 类的此代码创建 AttributeTable 。

    Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.ComponentModel
Imports System.Windows.Media
Imports System.Windows.Controls
Imports System.Windows

Imports Microsoft.Windows.Design.Features
Imports Microsoft.Windows.Design.Metadata
Imports SkewButtonLibrary.VisualStudio.Design

Imports SkewButtonLibrary

' The ProvideMetadata assembly-level attribute indicates to designers
' that this assembly contains a class that provides an attribute table. 
<Assembly: ProvideMetadata(GetType(SkewButtonLibrary.VisualStudio.Design.Metadata))> 

' Container for any general design-time metadata to initialize.
' Designers look for a type in the design-time assembly that 
' implements IProvideAttributeTable. If found, designers instantiate
' this class and access its AttributeTable property automatically.
Friend Class Metadata
    Implements IProvideAttributeTable

    ' Accessed by the designer to register any design-time metadata.
    Public ReadOnly Property AttributeTable() As AttributeTable _
        Implements IProvideAttributeTable.AttributeTable
        Get
            Dim builder As New AttributeTableBuilder()

            ' Add the adorner provider to the design-time metadata.
            builder.AddCustomAttributes( _
                GetType(SkewButton), _
                New FeatureAttribute(GetType(SkewButtonAdornerProvider)))

            Return builder.CreateTable()
        End Get
    End Property
End Class

    using System;
using System.Collections.Generic;
using System.Text;
using System.ComponentModel;
using System.Windows.Media;
using System.Windows.Controls;
using System.Windows;

using SkewButtonLibrary;
using Microsoft.Windows.Design.Features;
using Microsoft.Windows.Design.Metadata;
using SkewButtonLibrary.VisualStudio.Design;

[assembly: ProvideMetadata(typeof(SkewButtonLibrary.VisualStudio.Design.Metadata))]
namespace SkewButtonLibrary.VisualStudio.Design
{
    // Container for any general design-time metadata to initialize.
    // Designers look for a type in the design-time assembly that 
    // implements IProvideAttributeTable. If found, designers instantiate 
    // this class and access its AttributeTable property automatically.
    internal class Metadata : IProvideAttributeTable
    {
        // Accessed by the designer to register any design-time metadata.
        public AttributeTable AttributeTable
        {
            get
            {
                AttributeTableBuilder builder = new AttributeTableBuilder();

                // Add the adorner provider to the design-time metadata.
                builder.AddCustomAttributes(
                    typeof(SkewButton),
                    new FeatureAttribute(typeof(SkewButtonAdornerProvider)));

                return builder.CreateTable();
            }
        }
    }
}

  8. 保存解决方案。

实现装饰器提供程序

装饰器提供程序是在名为 SkewButtonAdornerProvider的类型中实现的。 此装饰器 FeatureProvider 启用设置控件的 RenderTransform 属性在设计时。

实现装饰器提供程序

  1. 将名为 SkewButtonAdornerProvider 的新类添加到 SkewButtonLibrary.VisualStudio.Design 项目。

  2. 在 SkewButtonAdornerProvider的代码编辑器中，用以下代码替换自动生成的代码。 提供自定义装饰器的此代码实现 PrimarySelectionAdornerProvider 。

    Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Windows.Input
Imports System.Windows
Imports System.Windows.Automation
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Shapes
Imports Microsoft.Windows.Design.Interaction
Imports Microsoft.Windows.Design.Model


' The following class implements an adorner provider for the 
' SkewButton control. The adorner is a slider control, which 
' changes the SkewTransform of the SkewButton along the x-axis. 
' The adorner is placed inside the adorned control.
Class SkewButtonAdornerProvider
    Inherits PrimarySelectionAdornerProvider
    Private adornedControlModel As ModelItem
    Private batchedChange As ModelEditingScope
    Private skewSlider As Slider
    Private skewSliderAdornerPanel As AdornerPanel

    Public Sub New() 
        skewSlider = New Slider()
    End Sub

    ' The following method is called when the adorner is activated.
    ' It creates the adorner control, sets up the adorner panel,
    ' and attaches a ModelItem to the SkewButton.
    Protected Overrides Sub Activate(ByVal item As ModelItem)
        ' Save the ModelItem and hook into when it changes.
        ' This enables updating the slider position when 
        ' a new background value is set.
        adornedControlModel = item
        AddHandler adornedControlModel.PropertyChanged, AddressOf AdornedControlModel_PropertyChanged

        ' Setup the slider's min and max values.
        skewSlider.Minimum = 0
        skewSlider.Maximum = 45

        ' Set the slider's background to the rail fill color.
        skewSlider.Background = AdornerColors.RailFillBrush

        ' All adorners are placed in an AdornerPanel
        ' for sizing and layout support.
        Dim panel As AdornerPanel = Me.Panel

        ' Position the slider as a rail inside the custom control.
        AdornerPanel.SetAdornerHorizontalAlignment(skewSlider, AdornerHorizontalAlignment.Stretch)
        AdornerPanel.SetAdornerVerticalAlignment(skewSlider, AdornerVerticalAlignment.Top)
        AdornerPanel.SetAdornerMargin(skewSlider, New Thickness(5, 5, 5, 0))

        ' Initialize the slider when it is loaded.
        AddHandler skewSlider.Loaded, AddressOf slider_Loaded

        ' Handle the value changes of the slider control.
        AddHandler skewSlider.ValueChanged, AddressOf slider_ValueChanged

        AddHandler skewSlider.PreviewMouseLeftButtonUp, AddressOf slider_MouseLeftButtonUp

        AddHandler skewSlider.PreviewMouseLeftButtonDown, AddressOf slider_MouseLeftButtonDown

        ' Run the base implementation.
        MyBase.Activate(item)

    End Sub

    ' The Panel utility property demand-creates the 
    ' adorner panel and adds it to the provider's 
    ' Adorners collection.
    Public ReadOnly Property Panel() As AdornerPanel
        Get
            If Me.skewSliderAdornerPanel Is Nothing Then
                Me.skewSliderAdornerPanel = New AdornerPanel()

                ' Add the adorner to the adorner panel.
                Me.skewSliderAdornerPanel.Children.Add(skewSlider)

                ' Add the panel to the Adorners collection.
                Adorners.Add(skewSliderAdornerPanel)
            End If

            Return Me.skewSliderAdornerPanel
        End Get
    End Property

    ' The following method deactivates the adorner.
    Protected Overrides Sub Deactivate() 

        RemoveHandler adornedControlModel.PropertyChanged, AddressOf AdornedControlModel_PropertyChanged

        MyBase.Deactivate()

    End Sub


    ' The following method handles the Loaded event.
    ' It assigns the slider control's initial value.
    Sub slider_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs) 
        skewSlider.Value = GetCurrentSkewAngle()

    End Sub


    ' The following method handles the PropertyChanged event.
    ' It updates the slider control's value if the SkewButton control's 
    ' RenderTransform property changed.
    Sub AdornedControlModel_PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) 
        If e.PropertyName = "RenderTransform" Then
            ' Assign the SkewButton control's skew angle to the slider.
            skewSlider.Value = GetCurrentSkewAngle()
        End If

    End Sub


    ' The following method handles the MouseLeftButtonDown event.
    ' It calls the BeginEdit method on the ModelItem which represents the
    ' Skewcontrol.
    Sub slider_MouseLeftButtonDown(ByVal sender As Object, ByVal e As System.Windows.Input.MouseButtonEventArgs) 
        batchedChange = adornedControlModel.BeginEdit()

    End Sub


    ' The following method handles the MouseLeftButtonUp event.
    ' It commits any changes made to the ModelItem which represents the
    ' Skewcontrol.
    Sub slider_MouseLeftButtonUp(ByVal sender As Object, ByVal e As System.Windows.Input.MouseButtonEventArgs) 
        If Not (batchedChange Is Nothing) Then
            batchedChange.Complete()
            batchedChange.Dispose()
            batchedChange = Nothing
        End If

    End Sub


    ' The following method handles the slider control's 
    ' ValueChanged event. It sets the value of the 
    ' RenderTransform property by using the ModelProperty
    ' type.
    Sub slider_ValueChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Double))

        Dim newSkewValue As Double = e.NewValue

        ' During setup, don't make a value local and set the skew angle.
        If newSkewValue = GetCurrentSkewAngle() Then
            Return
        End If

        ' Access the SkewButton control's RenderTransform property
        ' by using the ModelProperty type.
        Dim skewProperty As ModelProperty = adornedControlModel.Properties("RenderTransform")

        If Not skewProperty.IsSet Then
            ' If the value isn't local, make it local 
            ' before setting a sub-property value.
            skewProperty.SetValue(skewProperty.ComputedValue)
        End If

        ' Set the RenderTransform property on the SkewButton.
        skewProperty.SetValue(New SkewTransform(newSkewValue, 0))

    End Sub

    ' This utility method gets the SkewControl control's
    ' skew angle by using the ModelItem.
    Private Function GetCurrentSkewAngle()
        Dim skewXform As SkewTransform = adornedControlModel.Properties("RenderTransform").ComputedValue
        Return skewXform.AngleX
    End Function

End Class

    using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Input;
using System.Windows;
using System.Windows.Automation;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;
using Microsoft.Windows.Design.Interaction;
using Microsoft.Windows.Design.Model;

namespace SkewButtonLibrary.VisualStudio.Design
{
    // The following class implements an adorner provider for the 
    // SkewButton control. The adorner is a slider control, which 
    // changes the SkewTransform of the SkewButton along the x-axis. 
    // The adorner is placed inside the adorned control.
    class SkewButtonAdornerProvider : PrimarySelectionAdornerProvider
    {
        private ModelItem adornedControlModel;
        private ModelEditingScope batchedChange;
        private Slider skewSlider;
        private AdornerPanel skewButtonAdornerPanel;

        public SkewButtonAdornerProvider()
        {
            skewSlider = new Slider();
        }

        // The following method is called when the adorner is activated.
        // It creates the adorner control, sets up the adorner panel,
        // and attaches a ModelItem to the SkewButton.
        protected override void Activate(ModelItem item)
        {
            // Save the ModelItem and hook into when it changes.
            // This enables updating the slider position when 
            // a new background value is set.
            adornedControlModel = item;
            adornedControlModel.PropertyChanged += 
                new System.ComponentModel.PropertyChangedEventHandler(
                    AdornedControlModel_PropertyChanged);

            // Setup the slider's min and max values.
            skewSlider.Minimum = 0;
            skewSlider.Maximum = 45;

            // Set the slider's background to the rail fill color.
            skewSlider.Background = AdornerColors.RailFillBrush;

            // All adorners are placed in an AdornerPanel
            // for sizing and layout support.
            AdornerPanel panel = this.Panel;

            AdornerPanel.SetAdornerHorizontalAlignment(skewSlider, AdornerHorizontalAlignment.Stretch);
            AdornerPanel.SetAdornerVerticalAlignment(skewSlider, AdornerVerticalAlignment.Top);
            AdornerPanel.SetAdornerMargin(skewSlider, new Thickness(5, 5, 5, 0));

            // Initialize the slider when it is loaded.
            skewSlider.Loaded += new RoutedEventHandler(slider_Loaded);

            // Handle the value changes of the slider control.
            skewSlider.ValueChanged += 
                new RoutedPropertyChangedEventHandler<double>(
                    slider_ValueChanged);

            skewSlider.PreviewMouseLeftButtonUp += 
                new System.Windows.Input.MouseButtonEventHandler(
                    slider_MouseLeftButtonUp);

            skewSlider.PreviewMouseLeftButtonDown += 
                new System.Windows.Input.MouseButtonEventHandler(
                    slider_MouseLeftButtonDown);

            // Run the base implementation.
            base.Activate(item);
        }

        // The Panel utility property demand-creates the 
        // adorner panel and adds it to the provider's 
        // Adorners collection.
        public AdornerPanel Panel
        {
            get
            {
                if (this.skewButtonAdornerPanel == null)
                {
                    skewButtonAdornerPanel = new AdornerPanel();

                    skewButtonAdornerPanel.Children.Add(skewSlider);

                    // Add the panel to the Adorners collection.
                    Adorners.Add(skewButtonAdornerPanel);
                }

                return this.skewButtonAdornerPanel;
            }
        }

        // The following method deactivates the adorner.
        protected override void Deactivate()
        {
            adornedControlModel.PropertyChanged -= 
                new System.ComponentModel.PropertyChangedEventHandler(
                    AdornedControlModel_PropertyChanged);

            base.Deactivate();
        }

        // The following method handles the Loaded event.
        // It assigns the slider control's initial value.
        void slider_Loaded(object sender, RoutedEventArgs e)
        {   
            skewSlider.Value = GetCurrentSkewAngle();
        }

        // The following method handles the PropertyChanged event.
        // It updates the slider control's value if the SkewButton control's 
        // RenderTransform property changed.
        void AdornedControlModel_PropertyChanged(
            object sender, 
            System.ComponentModel.PropertyChangedEventArgs e)
        {
            if (e.PropertyName == "RenderTransform")
            {
                // Assign the SkewButton control's skew angle to the slider.
                skewSlider.Value = GetCurrentSkewAngle();
            }
        }

        // The following method handles the MouseLeftButtonDown event.
        // It calls the BeginEdit method on the ModelItem which represents the
        // Skewcontrol.
        void slider_MouseLeftButtonDown(
            object sender, 
            System.Windows.Input.MouseButtonEventArgs e)
        {
            batchedChange = adornedControlModel.BeginEdit();
        }

        // The following method handles the MouseLeftButtonUp event.
        // It commits any changes made to the ModelItem which represents the
        // Skewcontrol.
        void slider_MouseLeftButtonUp(
            object sender, 
            System.Windows.Input.MouseButtonEventArgs e)
        {
            if (batchedChange != null)
            {
                batchedChange.Complete();
                batchedChange.Dispose();
                batchedChange = null;
            }
        }

        // The following method handles the slider control's 
        // ValueChanged event. It sets the value of the 
        // RenderTransform property by using the ModelProperty
        // type.
        void slider_ValueChanged(
            object sender, 
            RoutedPropertyChangedEventArgs<double> e)
        {
            double newSkewValue = e.NewValue;

            // During setup, don't make a value local and set the skew angle.
            if (newSkewValue == GetCurrentSkewAngle())
            {
                return;
            }

            // Access the SkewButton control's RenderTransform property
            // by using the ModelProperty type.
            ModelProperty skewProperty = 
                adornedControlModel.Properties["RenderTransform"];

            if (!skewProperty.IsSet)
            {
                // If the value isn't local, make it local 
                // before setting a sub-property value.
                skewProperty.SetValue(skewProperty.ComputedValue);
            }

            // Set the RenderTransform property on the SkewButton.
            skewProperty.SetValue(new SkewTransform(newSkewValue, 0));
        }

        // This utility method gets the SkewControl control's
        // skew angle by using the ModelItem.
        private double GetCurrentSkewAngle()
        {   
            SkewTransform skewXform = adornedControlModel.Properties[
                "RenderTransform"].ComputedValue as SkewTransform;

            return skewXform.AngleX;
        }
    }
}

  3. 生成解决方案。

测试设计时实现

代码，就象使用任何其他 WPF 控件，可以使用 SkewButton 控件。 WPF Designer 处理所有设计时对象的创建。

测试设计时实现

  1. 新的 WPF 应用程序项目添加名为 DemoApplication 到解决方案。

    在 MainWindow.xaml WPF Designer打开。

  2. 添加对 SkewButtonLibrary 项目。

  3. 在 XAML 视图中，用以下 XAML 替换自动生成的 XAML。 此 XAML 将添加对 SkewButtonLibrary 命名空间并添加 SkewButton 自定义控件。 该按钮出现在且带有文本 “已激活设计模式”设计 " 视图中，表明该按钮处于设计模式下。 如果该按钮未出现，可能需要单击设计器顶部的信息栏以重新加载视图。

    <Window x:Class="DemoApplication.MainWindow"
    xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:cc="clr-namespace:SkewButtonLibrary;assembly=SkewButtonLibrary"
    Title="Window1" Height="300" Width="300">
    <Grid>
        <cc:SkewButton Margin="30,30,30,30" Background="#FFD4D0C8">
            <cc:SkewButton.RenderTransform>
                <SkewTransform AngleX="0" AngleY="0" />
            </cc:SkewButton.RenderTransform>
        </cc:SkewButton>
    </Grid>
</Window>

  4. 在设计视图中，单击 SkewButton 选择控件。

    Slider 控件显示在 SkewButton 控件内。 如果滑块控件未出现，尝试重新生成解决方案。

  5. 更改滑块控件的值。

    ，当您拖动滑块时，控件将发生扭曲。 在 XAML 视图中， RenderTransform 属性设置为装饰器指定的值。

  6. 运行 DemoApplication 项目。

    在运行时，该按钮将按您用装饰器设置的角度。

后续步骤

可以添加更多的自定义设计时功能。您的自定义控件。

请参见

参考

PrimarySelectionAdornerProvider

SkewTransform

其他资源

WPF 设计器扩展性示例

高级扩展性概念

WPF 设计器扩展性