走进WPF之开发类似Visio软件

当你想画一个流程图的时候，你会发现，很多软件要么需要秘钥，要么需要会员，这时我就在想，可不可自己制作一款流程图软件呢？本文以一个简单的小例子，简述如何利用WPF制作属于自己的流程图软件，仅供学习分享使用，如有不足之处，还请指正。

涉及知识点

本示例主要通过WPF技术进行开发，涉及知识点如下：

WPF绘图，如矩形，直线等功能的相关图形技术。
Thumb控件，本控件可以由用户自由拖动，示例中所用到的可移动的图形控件，都继承于Thumb控件。

Thumb控件简介

Thumb控件是WPF提供的用于用户拖动的控件。默认情况下，Thumb控件并不在工具箱中，需要手动添加，如下所示：

工具箱-->常规-->右键-->选择项，然后打开【选择工具箱对话框】，如下所示：

在选【择工具箱项】页面，打开WPF组件-->选择Thumb-->点击确定按钮，如下所示：

添加成功后，即可从工具箱拖动到页面，如下所示：

关于Thumb控件的简介，如下所示：

namespace System.Windows.Controls.Primitives
{//// 摘要://     表示可以由用户拖动的控件。[DefaultEvent("DragDelta")][Localizability(LocalizationCategory.NeverLocalize)]public class Thumb : Control{//// 摘要://     标识 System.Windows.Controls.Primitives.Thumb.DragStarted 路由事件。//// 返回结果://     System.Windows.Controls.Primitives.Thumb.DragStarted 路由事件的标识符。public static readonly RoutedEvent DragStartedEvent;//// 摘要://     标识 System.Windows.Controls.Primitives.Thumb.DragDelta 路由事件。//// 返回结果://     System.Windows.Controls.Primitives.Thumb.DragDelta 路由事件的标识符。public static readonly RoutedEvent DragDeltaEvent;//// 摘要://     标识 System.Windows.Controls.Primitives.Thumb.DragCompleted 路由事件。//// 返回结果://     System.Windows.Controls.Primitives.Thumb.DragCompleted 路由事件的标识符。public static readonly RoutedEvent DragCompletedEvent;//// 摘要://     标识 System.Windows.Controls.Primitives.Thumb.IsDragging 依赖属性。//// 返回结果://     System.Windows.Controls.Primitives.Thumb.IsDragging 依赖项属性的标识符。public static readonly DependencyProperty IsDraggingProperty;//// 摘要://     初始化 System.Windows.Controls.Primitives.Thumb 类的新实例。public Thumb();//// 摘要://     获取是否 System.Windows.Controls.Primitives.Thumb 控件具有逻辑焦点和捕获鼠标并按下鼠标左键。//// 返回结果://     true 如果 System.Windows.Controls.Primitives.Thumb 控件具有焦点且鼠标捕获; 否则为 false。 默认值为//     false。[Bindable(true)][Browsable(false)][Category("Appearance")]public bool IsDragging { get; protected set; }//// 摘要://     发生时 System.Windows.Controls.Primitives.Thumb 控件接收逻辑焦点和鼠标捕获。[Category("Behavior")]public event DragStartedEventHandler DragStarted;//// 摘要://     根据鼠标位置更改时出现了一个或多个次 System.Windows.Controls.Primitives.Thumb 控件具有逻辑焦点和鼠标捕获。[Category("Behavior")]public event DragDeltaEventHandler DragDelta;//// 摘要://     发生时 System.Windows.Controls.Primitives.Thumb 控件失去鼠标捕获。[Category("Behavior")]public event DragCompletedEventHandler DragCompleted;//// 摘要://     取消的拖动操作 System.Windows.Controls.Primitives.Thumb。public void CancelDrag();//// 摘要://     创建 System.Windows.Automation.Peers.AutomationPeer 为 System.Windows.Controls.Primitives.Thumb//     控件。//// 返回结果://     一个 System.Windows.Automation.Peers.ThumbAutomationPeer 为 System.Windows.Controls.Primitives.Thumb//     控件。protected override AutomationPeer OnCreateAutomationPeer();//// 摘要://     响应 System.Windows.Controls.Primitives.Thumb.IsDragging 属性值的更改。//// 参数://   e://     事件数据。protected virtual void OnDraggingChanged(DependencyPropertyChangedEventArgs e);//// 摘要://     提供类处理 System.Windows.ContentElement.MouseLeftButtonDown 事件。//// 参数://   e://     事件数据。protected override void OnMouseLeftButtonDown(MouseButtonEventArgs e);//// 摘要://     提供类处理 System.Windows.ContentElement.MouseLeftButtonUp 事件。//// 参数://   e://     事件数据。protected override void OnMouseLeftButtonUp(MouseButtonEventArgs e);//// 摘要://     提供类处理 System.Windows.UIElement.MouseMove 事件。//// 参数://   e://     事件数据。protected override void OnMouseMove(MouseEventArgs e);}
}

通过上述摘要简介，发现Thumb控件提供了三个事件，分别是：

拖动开始事件：public event DragStartedEventHandler DragStarted;
拖动进行事件：public event DragDeltaEventHandler DragDelta;
拖动完成事件：public event DragCompletedEventHandler DragCompleted;

Thumb控件示例

首先在窗口页面上添加一个Thumb控件，然后分别添加三个事件，如下所示：

<Window x:Class="DemoVisio.MainWindow1"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:local="clr-namespace:DemoVisio"mc:Ignorable="d"Title="Thumb示例" Height="450" Width="800"><Canvas><Thumb x:Name="thumb" Canvas.Left="0" Canvas.Top="0"  Height="100"  Width="100"   DragStarted="thumb_DragStarted" DragDelta="thumb_DragDelta" DragCompleted="thumb_DragCompleted"/></Canvas>
</Window>

然后在三个事件中添加代码，终点是DragDelta事件，如下所示：

namespace DemoVisio
{/// <summary>/// MainWindow1.xaml 的交互逻辑/// </summary>public partial class MainWindow1 : Window{public MainWindow1(){InitializeComponent();}private void thumb_DragStarted(object sender, DragStartedEventArgs e){//开始拖动}/// <summary>/// 拖动/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void thumb_DragDelta(object sender, System.Windows.Controls.Primitives.DragDeltaEventArgs e){Thumb myThumb = (Thumb)sender;double nTop = Canvas.GetTop(myThumb) + e.VerticalChange;double nLeft = Canvas.GetLeft(myThumb) + e.HorizontalChange;Canvas.SetTop(myThumb, nTop);Canvas.SetLeft(myThumb, nLeft);}private void thumb_DragCompleted(object sender, DragCompletedEventArgs e){//拖动完成}}
}

注意，在XAML中，Thumb一定是在Canvas布局容器中，且一定要设置【Canvas.Left="0" Canvas.Top="0"】两个属性，如果不设置，在值为NaN，无法进行拖动。

默认情况下，Thumb控件就是一个丑丑的方块，如下所示：

拖动控件基类

在本示例中，流程图需要多种控件（如：圆形，矩形，线等），不能每一个控件都去实现那三个事件【DragStarted，DragDelta，DragCompleted】，所以需要定义一个基类ThumbControl，统一实现方案。具体如下所示：

namespace DemoVisio
{public class ThumbControl : Thumb{/// <summary>/// 是否可以输入/// </summary>public bool IsEnableInput { get { return (bool)GetValue(IsEnableInputProperty); } set {SetValue( IsEnableInputProperty, value); } }/// <summary>/// 依赖属性/// </summary>public static readonly DependencyProperty IsEnableInputProperty = DependencyProperty.Register("IsEnableInput",typeof(bool),typeof(ThumbControl));public ThumbControl():base() {this.DragStarted += ThumbControl_DragStarted;this.DragDelta += ThumbControl_DragDelta;this.DragCompleted += ThumbControl_DragCompleted;this.MouseDoubleClick += ThumbControl_MouseDoubleClick;this.IsKeyboardFocusedChanged += ThumbControl_IsKeyboardFocusedChanged;}public void SetIsEnableInput(bool flag){this.IsEnableInput = flag;}/// <summary>/// 是否具有键盘焦点/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void ThumbControl_IsKeyboardFocusedChanged(object sender, DependencyPropertyChangedEventArgs e){this.IsEnableInput = this.IsKeyboardFocused;}/// <summary>/// 双击事件/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void ThumbControl_MouseDoubleClick(object sender, System.Windows.Input.MouseButtonEventArgs e){this.IsEnableInput = true;}private void ThumbControl_DragStarted(object sender, DragStartedEventArgs e){//开始移动}private void ThumbControl_DragDelta(object sender, DragDeltaEventArgs e){Thumb myThumb = (Thumb)sender;double nTop = Canvas.GetTop(myThumb) + e.VerticalChange;double nLeft = Canvas.GetLeft(myThumb) + e.HorizontalChange;Canvas.SetTop(myThumb, nTop);Canvas.SetLeft(myThumb, nLeft);}private void ThumbControl_DragCompleted(object sender, DragCompletedEventArgs e){//移动结束}}
}

具体图形控件

封装了基类以后，其他控件可以在此基础上进行使用，通过ControlTemplate展现不同的形态，如下所示：

1. 矩形方块

在流程图中，矩形方块一般表示过程，实现代码如下所示：

<UserControl x:Class="DemoVisio.SquareControl"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:local="clr-namespace:DemoVisio"mc:Ignorable="d"d:DesignHeight="450" d:DesignWidth="800"><Canvas><local:ThumbControl x:Name="s" BorderThickness="1" Canvas.Top ="0" Canvas.Left="0" Width="100" Height="60" Background="AliceBlue"><Thumb.Template><ControlTemplate><Border Width="{Binding ElementName=s, Path=Width}" Height="{Binding ElementName=s, Path=Height}" BorderBrush="Black" Background="{Binding ElementName=s, Path=Background}" BorderThickness="{Binding ElementName=s, Path=BorderThickness}" Padding="2"><TextBox Background="{Binding ElementName=s, Path=Background}" BorderThickness="0" VerticalAlignment="Center"  IsEnabled="{Binding ElementName=s, Path=IsEnableInput}" MinLines="3" MaxLines="3" HorizontalContentAlignment="Center" VerticalContentAlignment="Center"></TextBox></Border></ControlTemplate></Thumb.Template></local:ThumbControl></Canvas>
</UserControl>

2. 圆形图

在流程图中，圆形一般表示开始和结束，如下所示：

<UserControl x:Class="DemoVisio.CircleControl"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:local="clr-namespace:DemoVisio"mc:Ignorable="d"d:DesignHeight="450" d:DesignWidth="800"><Canvas><local:ThumbControl x:Name="s" Canvas.Top ="0" Canvas.Left="0" Width="60" Height="60" Background="AliceBlue" BorderThickness="1" ><local:ThumbControl.Template><ControlTemplate><Grid><Border Width="{Binding Width}" Height="{Binding Height}" CornerRadius="30" BorderThickness="{Binding ElementName=s, Path=BorderThickness}" BorderBrush="Black" Background="{Binding ElementName=s, Path=Background}"><TextBox VerticalAlignment="Center" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" MaxLines="2" MinLines="1" Width="{Binding Width}" Height="{Binding Height}" Background="{Binding ElementName=s, Path=Background}" BorderThickness="0" IsEnabled="{Binding ElementName=s, Path=IsEnableInput}"></TextBox></Border></Grid></ControlTemplate></local:ThumbControl.Template></local:ThumbControl></Canvas>
</UserControl>

3. 菱形图

在流程图中，菱形一般表示选择，表达程序中的布尔值。如下所示：

<UserControl x:Class="DemoVisio.RhombusControl"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:local="clr-namespace:DemoVisio"mc:Ignorable="d"d:DesignHeight="450" d:DesignWidth="800"><Canvas><local:ThumbControl x:Name="s" Canvas.Left="0" Canvas.Top="0"  Width="80" Height="80" Background="AliceBlue" BorderThickness="1"  ><Thumb.Template><ControlTemplate><Border Width="{Binding ElementName=s, Path=Width}" Height="{Binding ElementName=s, Path=Height}" BorderBrush="Black" Background="{Binding ElementName=s, Path=Background}" BorderThickness="{Binding ElementName=s, Path=BorderThickness}" Padding="1"><TextBox Background="{Binding ElementName=s, Path=Background}" BorderThickness="0" VerticalAlignment="Center"  IsEnabled="{Binding ElementName=s, Path=IsEnableInput}" Width="50" Height="50" HorizontalContentAlignment="Center" VerticalContentAlignment="Center"><TextBox.RenderTransform><RotateTransform CenterX="25" CenterY="25" Angle="-45" ></RotateTransform></TextBox.RenderTransform></TextBox></Border></ControlTemplate></Thumb.Template><Thumb.RenderTransform><TransformGroup><RotateTransform CenterX="40" CenterY="40" Angle="45"></RotateTransform><ScaleTransform CenterX="40" CenterY="40" ScaleX="0.8"></ScaleTransform><TranslateTransform X="10" Y="15"></TranslateTransform></TransformGroup></Thumb.RenderTransform></local:ThumbControl></Canvas>
</UserControl>

4. 直线

在流程图中，直线一般表示两个过程之间的连接，如下所示：

<UserControl x:Class="DemoVisio.LineArrowControl"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:local="clr-namespace:DemoVisio"mc:Ignorable="d"d:DesignHeight="450" d:DesignWidth="800"><Canvas><local:ThumbControl x:Name="s" Canvas.Left="0" Canvas.Top="0"  Width="100" Height="100" Background="AliceBlue" IsEnableInput="False"><local:ThumbControl.Template><ControlTemplate><Grid><Line X1="0" Y1="0" X2="0" Y2="100" Stroke="Black" StrokeThickness="2" HorizontalAlignment="Center" ></Line><Line X1="-5" Y1="90" X2="1" Y2="100" StrokeThickness="2" Stroke="Black" HorizontalAlignment="Center"></Line><Line X1="8" Y1="90" X2="3" Y2="100" StrokeThickness="2" Stroke="Black" HorizontalAlignment="Center"></Line><TextBox VerticalAlignment="Center" Height="30" HorizontalContentAlignment="Center" BorderThickness="0" VerticalContentAlignment="Center" MinLines="1" MaxLines="2" IsEnabled="{Binding ElementName=s, Path=IsEnableInput}" Opacity="0" Visibility="{Binding ElementName=s, Path=IsEnableInput}"></TextBox></Grid></ControlTemplate></local:ThumbControl.Template></local:ThumbControl></Canvas>
</UserControl>

主窗体

主窗体主要用于绘制流程图，分为左右两部分，左边是控件列表，右边是布局容器，如下所示：

<Window x:Class="DemoVisio.MainWindow"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:local="clr-namespace:DemoVisio"mc:Ignorable="d"Title="流程图" Height="800" Width="800" MouseDown="Window_MouseDown" Loaded="Window_Loaded"><Window.Resources><Style TargetType="TextBlock"><Setter Property="HorizontalAlignment" Value="Center"></Setter></Style></Window.Resources><Grid ShowGridLines="True"><Grid.ColumnDefinitions><ColumnDefinition Width="Auto" MinWidth="150"></ColumnDefinition><ColumnDefinition Width="*"></ColumnDefinition></Grid.ColumnDefinitions><StackPanel Grid.Column="0" x:Name="left" Orientation="Vertical"><Rectangle Width="80" Height="50" Fill="AliceBlue" Stroke="Black" Margin="5" x:Name="rectangle" MouseLeftButtonDown="rectangle_MouseLeftButtonDown"></Rectangle><TextBlock Text="矩形"></TextBlock><Rectangle Width="100" Height="100" Fill="AliceBlue" Stroke="Black" Margin="5" x:Name="rhombus" MouseLeftButtonDown="rhombus_MouseLeftButtonDown"><Rectangle.RenderTransform><TransformGroup><RotateTransform CenterX="50" CenterY="50" Angle="45"></RotateTransform><ScaleTransform CenterX="50" CenterY="50" ScaleX="0.5" ScaleY="0.7"></ScaleTransform></TransformGroup></Rectangle.RenderTransform></Rectangle><TextBlock Text="菱形" Margin="0,5"></TextBlock><Line X1="0" Y1="0" X2="0" Y2="80" Stroke="Black" StrokeThickness="2" HorizontalAlignment="Center" Margin="5" x:Name="line" MouseLeftButtonDown="line_MouseLeftButtonDown" ></Line><TextBlock Text="直线"></TextBlock><Ellipse Width="60" Height="60" Fill="AliceBlue" Stroke="Black" Margin="5" x:Name="circle" MouseLeftButtonDown="circle_MouseLeftButtonDown"></Ellipse><TextBlock Text="圆形"></TextBlock></StackPanel><Canvas Grid.Column="1" x:Name="right" ></Canvas></Grid>
</Window>

当点击左边基础控件时，在右边容器中，生成新的控件。如下所示：

namespace DemoVisio
{/// <summary>/// MainWindow.xaml 的交互逻辑/// </summary>public partial class MainWindow : Window{/// <summary>/// 控件列表/// </summary>private List<Control> rightControls = new List<Control>();public MainWindow(){InitializeComponent();}private void Window_MouseDown(object sender, MouseButtonEventArgs e){//this.Focus();//this.one.SetIsEnableInput(false);foreach (var control in this.right.Children) {var thumb = control as ThumbControl;if (thumb != null){thumb.SetIsEnableInput(false);}}}private void Window_Loaded(object sender, RoutedEventArgs e){var width = this.right.ActualWidth;var height = this.right.ActualHeight;int x = 0;int y = 0;//横线while (y<height) {Line line = new Line();line.X1 = x;line.Y1 = y;line.X2 = width;line.Y2 = y;line.Stroke = Brushes.LightGray;line.StrokeThickness = 1;this.right.Children.Add(line);y = y + 10;}//重新初始化值x = 0;y = 0;//竖线while (x < width) {Line line = new Line();line.X1 = x;line.Y1 = y;line.X2 = x;line.Y2 = height;line.Stroke = Brushes.LightGray;line.StrokeThickness = 1;this.right.Children.Add(line);x = x + 10;}}private void rectangle_MouseLeftButtonDown(object sender, MouseButtonEventArgs e){SquareControl squareControl = new SquareControl();this.right.Children.Add(squareControl);}private void rhombus_MouseLeftButtonDown(object sender, MouseButtonEventArgs e){RhombusControl rhombusControl = new RhombusControl();this.right.Children.Add(rhombusControl);}private void line_MouseLeftButtonDown(object sender, MouseButtonEventArgs e){LineArrowControl lineArrowControl = new LineArrowControl();this.right.Children.Add(lineArrowControl);}private void circle_MouseLeftButtonDown(object sender, MouseButtonEventArgs e){CircleControl circleControl = new CircleControl();this.right.Children.Add(circleControl);}}
}

示例截图

示例基础截图如下所示：

备注

以上示例只是基础，功能并不完善，旨在抛砖引玉，共同学习，一起进步，希望可以对大家有所启发。

贺新郎·九日

【作者】刘克庄【朝代】宋

湛湛长空黑。更那堪、斜风细雨，乱愁如织。

老眼平生空四海，赖有高楼百尺。

看浩荡、千崖秋色。

白发书生神州泪，尽凄凉、不向牛山滴。

追往事，去无迹。

少年自负凌云笔。到而今、春华落尽，满怀萧瑟。

常恨世人新意少，爱说南朝狂客。

把破帽、年年拈出。

若对黄花孤负酒，怕黄花、也笑人岑寂。

鸿北去，日西匿。