Silverlight WorkFlow画图--ArrowLine画线

前面说了一下Activity控件

现在说一下ArrowLine画线控件

ArrowLine可以分为三部分：箭头、线、箭尾组成。

当点击Activity里面圆时，线就出来了，然后拖动，将箭头指向目标Activity控件里去

然后松开鼠标，这样一根线就画出来了。

如图所示：

当拖动开始节点Activity控件时，线的尾部坐标也得修改相应的坐标，同里当拖动结束节点Activity的时候，箭头的坐标也得及时更新位置

当不想要线的时候，可以点击线的右键，然后将线删除。

ArrowLine控件的xaml描述如下：

 <Canvas  x:Name="LayoutRoot" Background="White">        <Line x:Name="Cap">            <Line.RenderTransform>                <RotateTransform x:Name="CapRotateTransform" />            </Line.RenderTransform>        </Line>        <Line x:Name="Connector" />        <Line x:Name="Foot">            <Line.RenderTransform>                <RotateTransform x:Name="FootRotateTransform" />            </Line.RenderTransform>        </Line>        <TextBox Name="txtComment" Visibility="Collapsed" Text="请输入说明..." TextWrapping="Wrap" AcceptsReturn="True" VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto" />    </Canvas >

ArrowLine控件的cs代码如下：

下面里的代码有从网上摘出来的，修改了一下。

public partial class ArrowLine : UserControl, IArrowLine    {        /// <summary>        /// 删除箭头        /// </summary>        public event RoutedEventHandler DeleteLine;        Point startPoint;        Point endPoint;        /// <summary>        /// 右键菜单        /// </summary>        ContextMenu _Cmenu = new ContextMenu();        string _LineGuid;        /// <summary>        /// 线的GUID值        /// </summary>        public string LineGuid { get { return _LineGuid; } set { _LineGuid = value; } }        /// <summary>        /// 箭头尾部所在的控件        /// </summary>        public UIElement ArrowFootControl { get; set; }        /// <summary>        /// 箭头头部所在的控件        /// </summary>        public UIElement ArrowCapControl { get; set; }        /// <summary>        /// 开始坐标        /// </summary>        public Point StartPoint        {            get { return startPoint; }            set            {                startPoint = value;                Update();            }        }        /// <summary>        /// 结束坐标        /// </summary>        public Point EndPoint        {            get { return endPoint; }            set            {                endPoint = value;                Update();            }        }        public ArrowLine()        {            InitializeComponent();            MenuItem mi = new MenuItem();            mi.Click += new RoutedEventHandler(mi_Click);            mi.Header = "删除";            mi.Tag = "delete";            _Cmenu.Items.Add(mi);            _Cmenu.Visibility = System.Windows.Visibility.Collapsed;            mi = new MenuItem();            mi.Click += new RoutedEventHandler(mi_Click);            mi.Header = "说明";            mi.Tag = "Comment";            _Cmenu.Items.Add(mi);            this.MouseRightButtonDown += new MouseButtonEventHandler(ArrowLine_MouseRightButtonDown);            this.txtComment.LostFocus += new RoutedEventHandler(txtComment_LostFocus);            this.LayoutRoot.Children.Add(_Cmenu);        }        void txtComment_LostFocus(object sender, RoutedEventArgs e)        {            if (txtComment.Text.IsNullOrEmpty() || txtComment.Text.Equals("请输入说明..."))            {                txtComment.Visibility = System.Windows.Visibility.Collapsed;            }            else            {                txtComment.IsEnabled = false;            }        }        void ArrowLine_MouseRightButtonDown(object sender, MouseButtonEventArgs e)        {            e.Handled = true;            var p = e.GetPosition(sender as UIElement);            Canvas.SetLeft(_Cmenu, p.X);            Canvas.SetTop(_Cmenu, p.Y);            _Cmenu.Visibility = System.Windows.Visibility.Visible;        }        void mi_Click(object sender, RoutedEventArgs e)        {            MenuItem mi = sender as MenuItem;            string state = mi.Tag.ToString();            switch (state)            {                case "delete":                    if (null != DeleteLine)                    {                        DeleteLine(this, e);                    }                    break;                case "Comment":                    txtComment.IsEnabled = true;                    txtComment.Visibility = System.Windows.Visibility.Visible;                    break;            }            _Cmenu.Visibility = System.Windows.Visibility.Collapsed;        }        /// <summary>        /// 结构函数        /// </summary>        /// <param name="startPoint">开始坐标</param>        /// <param name="endPoint">结束坐标</param>        public ArrowLine(Point startPoint, Point endPoint)            : this()        {            this.startPoint = startPoint;            this.endPoint = endPoint;            Update();        }        /// <summary>        /// 更新        /// </summary>        private void Update()        {            double angleOfLine = Math.Atan2((endPoint.Y - startPoint.Y), (endPoint.X - startPoint.X)) * 180 / Math.PI;            Connector.X1 = startPoint.X;            Connector.Y1 = startPoint.Y;            Connector.X2 = endPoint.X;            Connector.Y2 = endPoint.Y;            Connector.StrokeThickness = 1;            Connector.Stroke = new SolidColorBrush(Colors.Black);            Cap.X1 = (startPoint.X + endPoint.X) / 2;            Cap.Y1 = (startPoint.Y + endPoint.Y) / 2;            Cap.X2 = (startPoint.X + endPoint.X) / 2;            Cap.Y2 = (startPoint.Y + endPoint.Y) / 2;            Cap.StrokeEndLineCap = PenLineCap.Triangle;            Cap.StrokeThickness = 20;            Cap.Stroke = new SolidColorBrush(Colors.Black);            CapRotateTransform.Angle = angleOfLine;            CapRotateTransform.CenterX = (this.StartPoint.X + this.endPoint.X) / 2;            CapRotateTransform.CenterY = (this.StartPoint.Y + this.endPoint.Y) / 2;            Foot.X1 = endPoint.X;            Foot.Y1 = endPoint.Y;            Foot.X2 = endPoint.X;            Foot.Y2 = endPoint.Y;            Foot.StrokeEndLineCap = PenLineCap.Triangle;            Foot.StrokeThickness = 20;            Foot.Stroke = new SolidColorBrush(Colors.Black);            FootRotateTransform.Angle = angleOfLine;            FootRotateTransform.CenterX = this.EndPoint.X;            FootRotateTransform.CenterY = this.EndPoint.Y;            Canvas.SetLeft(txtComment, (this.endPoint.X + this.startPoint.X) / 2);            Canvas.SetTop(txtComment, (this.endPoint.Y + this.startPoint.Y) / 2);        }        /// <summary>        /// 释放内存        /// </summary>        public void Dispose()        {            try            {                foreach (var v in _Cmenu.Items)                {                    MenuItem mi = v as MenuItem;                    if (null == mi)                    {                        continue;                    }                    mi.Click -= mi_Click;                }                this.MouseRightButtonDown -= ArrowLine_MouseRightButtonDown;                this.txtComment.LostFocus -= txtComment_LostFocus;            }            catch { }        }        /// <summary>        /// 导出描述线信息        /// </summary>        /// <returns></returns>        public string ExportLocation()        {            ArrowLineInfo ail = new ArrowLineInfo();            ail.Type = this.GetType().Name;            ail.Name = this.Name;            ail.Guid = this.LineGuid;            ail.StartX = StartPoint.X;            ail.StartY = StartPoint.Y;            ail.EndX = EndPoint.X;            ail.EndY = EndPoint.Y;            var aa = ail.ToXElement("ArrowLine");            return aa.ToString();        }    }