本章包含以下内容：
l 规则曲线支持两个中间点的移动
l 双击规则中间点，自定对齐曲线
l 增加选定活动的左右、上下对齐功能
在前面的规则图形中，也支持曲线类型的线条，但是线条的转折点是自动生成的，根据网友的反馈，希望增加可以用户自己移动的转折点，效果图如下：无图
为了使得程序清晰，更加面向对象，对于转折点我们使用一个单独的类（用户控件）来表示，这个转折点类只包含一个圆（Ellipse）。Xmal代码如下： 转折点是动态增加到规则类中的，转折点向外暴露两个事件。 l 转折点拖拽移动事件：当转折点被鼠标拖拽移动时，需要重新设置规则的直线坐标点。 l 转折点双击事件：当双击转折点时，需要重新设定规则的直线坐标，自动对其线段。 转折点包含两个重要的属性： l Radius：转折点图形的半径。 l CenterPosition：转折点的中心坐标(相对Canvas的坐标 )。 下面是转折点类的代码： 对于选中的活动，可以按照下面4种方式对齐： l 向左对齐：选中活动的X坐标设置为其中X坐标最小的值。 l 向右对齐：选中活动的X坐标设置为其中X坐标最大的值。 l 向上对齐：选中活动的Y坐标设置为其中X坐标最小的值。 l 向下对齐：选中活动的Y坐标设置为其中X坐标最大的值。 为了需要两次遍历选中的活动集合。第一次遍历取得其中X/Y坐标的最小/最大值，第二次遍历设置活动的X/Y坐标为最小/最大值。 代码如下所示： 
<UserControl x:Class="Shareidea.Web.UI.Control.Workflow.Designer.RuleTurnPoint"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" >
<Canvas>
<Canvas.Resources>
<Storyboard x:Name="sbDisplay">
<DoubleAnimation From="0" To="0.8" Duration="00:00:1.0"
Storyboard.TargetName="eliTurnPoint"
Storyboard.TargetProperty="Opacity" >
</DoubleAnimation>
</Storyboard>
<Storyboard x:Name="sbColse">
<DoubleAnimation From="0.8" To="0.0" Duration="00:00:1.0"
Storyboard.TargetName="eliTurnPoint"
Storyboard.TargetProperty="Opacity" >
</DoubleAnimation>
</Storyboard>
</Canvas.Resources>
<Ellipse Name="eliTurnPoint" Width="8" Height="8" Fill="Green" Opacity="0.8"
MouseLeftButtonDown="Canvas_MouseLeftButtonDown"
MouseLeftButtonUp="Canvas_MouseLeftButtonUp"
MouseMove="Canvas_MouseMove"
></Ellipse>
</Canvas>
</UserControl>
public partial class RuleTurnPoint : UserControl
{
public delegate void RuleTurnPointMoveDelegate(object sender, MouseEventArgs e, Point newPoint);
public delegate void DoubleClickDelegate(object sender, EventArgs e);
public event RuleTurnPointMoveDelegate RuleTurnPointMove;
public RuleTurnPoint()
{
InitializeComponent();
_doubleClickTimer = new System.Windows.Threading.DispatcherTimer();
_doubleClickTimer.Interval = new TimeSpan(0, 0, 0, 0, 200);
_doubleClickTimer.Tick += new EventHandler(_doubleClickTimer_Tick);
}
void _doubleClickTimer_Tick(object sender, EventArgs e)
{
_doubleClickTimer.Stop();
}
public Brush Fill
{
get
{
return eliTurnPoint.Fill;
}
set
{
eliTurnPoint.Fill = value;
}
}
public void ShowDisplayAutomation()
{
sbDisplay.Begin();
}
public void ShowCloseAutomation()
{
sbColse.Begin();
}
private void Canvas_MouseEnter(object sender, MouseEventArgs e)
{
}
Point mousePosition;
bool trackingMouseMove = false;
bool hadActualMove = false;
System.Windows.Threading.DispatcherTimer _doubleClickTimer;
public event DoubleClickDelegate OnDoubleClick;
private void Canvas_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
e.Handled = true;
if (_doubleClickTimer.IsEnabled)
{
_doubleClickTimer.Stop();
if (OnDoubleClick != null)
OnDoubleClick(this, e);
}
else
{
_doubleClickTimer.Start();
FrameworkElement element = sender as FrameworkElement;
mousePosition = e.GetPosition(null);
trackingMouseMove = true;
hadActualMove = false;
if (null != element)
{
element.CaptureMouse();
element.Cursor = Cursors.Hand;
}
}
}
private void Canvas_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
e.Handled = true;
FrameworkElement element = sender as FrameworkElement;
hadActualMove = false;
trackingMouseMove = false;
element.ReleaseMouseCapture();
mousePosition = e.GetPosition(null);
element.Cursor = null;
}
public double Radius
{
get
{
return eliTurnPoint.Width / 2;
}
}
public Point CenterPosition {
get
{
return new Point((double)this.GetValue(Canvas.LeftProperty) + Radius, (double)this.GetValue(Canvas.TopProperty) + Radius);
}
set
{
this.SetValue(Canvas.LeftProperty, value.X - Radius);
this.SetValue(Canvas.TopProperty, value.Y - Radius);
}
}
private void Canvas_MouseMove(object sender, MouseEventArgs e)
{
if (trackingMouseMove)
{
FrameworkElement element = sender as FrameworkElement;
element.Cursor = Cursors.Hand;
if (e.GetPosition(null) == mousePosition)
return;
hadActualMove = true;
double deltaV = e.GetPosition(null).Y - mousePosition.Y;
double deltaH = e.GetPosition(null).X - mousePosition.X;
double newTop = deltaV + CenterPosition.Y;
double newLeft = deltaH + CenterPosition.X;
Point p = new Point(newLeft, newTop);
CenterPosition = p;
if (RuleTurnPointMove != null)
{
RuleTurnPointMove(sender, e,p);
}
mousePosition = e.GetPosition(null);
}
}
}6.9 活动对齐功能
public void AlignTop()
{
if (CurrentSelectedControlCollection == null || CurrentSelectedControlCollection.Count == 0)
return;
Activity a = null;
double minY = 100000.0;
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
if (a.CenterPoint.Y < minY)
minY = a.CenterPoint.Y;
}
}
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
a.CenterPoint = new Point(a.CenterPoint.X, minY);
}
}
}
public void AlignBottom()
{
if (CurrentSelectedControlCollection == null || CurrentSelectedControlCollection.Count == 0)
return;
Activity a = null;
double maxY = 0;
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
if (a.CenterPoint.Y >maxY)
maxY = a.CenterPoint.Y;
}
}
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
a.CenterPoint = new Point(a.CenterPoint.X, maxY);
}
}
}
public void AlignLeft()
{
if (CurrentSelectedControlCollection == null || CurrentSelectedControlCollection.Count == 0)
return;
Activity a = null;
double minX = 100000.0;
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
if (a.CenterPoint.X < minX)
minX = a.CenterPoint.X;
}
}
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
a.CenterPoint = new Point(minX, a.CenterPoint.Y);
}
}
}
public void AlignRight()
{
if (CurrentSelectedControlCollection == null || CurrentSelectedControlCollection.Count == 0)
return;
Activity a = null;
double maxX = 0;
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
if (a.CenterPoint.X > maxX)
maxX = a.CenterPoint.X;
}
}
for (int i = 0; i < CurrentSelectedControlCollection.Count; i++)
{
if (CurrentSelectedControlCollection[i] is Activity)
{
a = CurrentSelectedControlCollection[i] as Activity;
a.CenterPoint = new Point(maxX, a.CenterPoint.Y);
}
}
}
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