1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
|
namespace System.Workflow.Activities
{
#region Imports
using System;
using System.Text;
using System.Reflection;
using System.Collections;
using System.CodeDom;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Drawing;
using System.Workflow.ComponentModel;
using System.Workflow.ComponentModel.Design;
using System.Collections.Generic;
using System.Workflow.ComponentModel.Compiler;
#endregion
[SRDescription(SR.SequenceActivityDescription)]
[ToolboxItem(typeof(ActivityToolboxItem))]
[Designer(typeof(SequenceDesigner), typeof(IDesigner))]
[ToolboxBitmap(typeof(SequenceActivity), "Resources.Sequence.png")]
[SRCategory(SR.Standard)]
[Obsolete("The System.Workflow.* types are deprecated. Instead, please use the new types from System.Activities.*")]
public class SequenceActivity : CompositeActivity, IActivityEventListener<ActivityExecutionStatusChangedEventArgs>
{
#region Constructors
public SequenceActivity()
{
}
public SequenceActivity(string name)
: base(name)
{
}
#endregion
private static readonly DependencyProperty SequenceFaultingProperty = DependencyProperty.Register("SequenceFaulting", typeof(bool), typeof(SequenceActivity));
private static readonly DependencyProperty ActiveChildQualifiedNameProperty = DependencyProperty.Register("ActiveChildQualifiedName", typeof(string), typeof(SequenceActivity));
[NonSerialized]
private bool activeChildRemovedInDynamicUpdate = false;
#region Protected Methods
protected override ActivityExecutionStatus Execute(ActivityExecutionContext executionContext)
{
if (executionContext == null)
throw new ArgumentNullException("executionContext");
if (this.EnabledActivities.Count == 0)
{
OnSequenceComplete(executionContext);
return ActivityExecutionStatus.Closed;
}
else
{
this.EnabledActivities[0].RegisterForStatusChange(Activity.ClosedEvent, this);
executionContext.ExecuteActivity(this.EnabledActivities[0]);
this.SetValue(ActiveChildQualifiedNameProperty, this.EnabledActivities[0].QualifiedName);
return ActivityExecutionStatus.Executing;
}
}
protected override ActivityExecutionStatus Cancel(ActivityExecutionContext executionContext)
{
if (executionContext == null)
throw new ArgumentNullException("executionContext");
for (int i = (this.EnabledActivities.Count - 1); i >= 0; i--)
{
Activity childActivity = this.EnabledActivities[i];
if (childActivity.ExecutionStatus == ActivityExecutionStatus.Executing)
{
executionContext.CancelActivity(childActivity);
return ActivityExecutionStatus.Canceling;
}
if (childActivity.ExecutionStatus == ActivityExecutionStatus.Canceling || childActivity.ExecutionStatus == ActivityExecutionStatus.Faulting)
return ActivityExecutionStatus.Canceling;
if (childActivity.ExecutionStatus == ActivityExecutionStatus.Closed)
{
this.RemoveProperty(ActiveChildQualifiedNameProperty);
return ActivityExecutionStatus.Closed;
}
}
return ActivityExecutionStatus.Closed;
}
protected override ActivityExecutionStatus HandleFault(ActivityExecutionContext executionContext, Exception exception)
{
this.SetValue(SequenceFaultingProperty, true);
ActivityExecutionStatus executionStatus = base.HandleFault(executionContext, exception);
if (executionStatus == ActivityExecutionStatus.Closed)
this.RemoveProperty(SequenceFaultingProperty);
return executionStatus;
}
#endregion
#region IActivityEventListener<ActivityStatusChangeEventArgs> Implementation
void IActivityEventListener<ActivityExecutionStatusChangedEventArgs>.OnEvent(Object sender, ActivityExecutionStatusChangedEventArgs e)
{
if (sender == null)
throw new ArgumentNullException("sender");
if (e == null)
throw new ArgumentNullException("e");
ActivityExecutionContext context = sender as ActivityExecutionContext;
if (context == null)
throw new ArgumentException(SR.Error_SenderMustBeActivityExecutionContext, "sender");
e.Activity.UnregisterForStatusChange(Activity.ClosedEvent, this);
SequenceActivity sequenceActivity = context.Activity as SequenceActivity;
if (sequenceActivity == null)
throw new ArgumentException("sender");
if (sequenceActivity.ExecutionStatus == ActivityExecutionStatus.Canceling ||
(sequenceActivity.ExecutionStatus == ActivityExecutionStatus.Faulting) &&
(bool)this.GetValue(SequenceFaultingProperty))
{
if (sequenceActivity.ExecutionStatus == ActivityExecutionStatus.Faulting)
this.RemoveProperty(SequenceFaultingProperty);
this.RemoveProperty(ActiveChildQualifiedNameProperty);
context.CloseActivity();
}
else if (sequenceActivity.ExecutionStatus == ActivityExecutionStatus.Executing)
{
if (!TryScheduleNextChild(context))
{
OnSequenceComplete(context);
context.CloseActivity();
}
}
}
#endregion
#region Private Implementation
private bool TryScheduleNextChild(ActivityExecutionContext executionContext)
{
if (executionContext == null)
throw new ArgumentNullException("executionContext");
IList<Activity> seqList = this.EnabledActivities;
if (seqList.Count == 0)
return false;
//Find index of next activity to run.
int indexOfNextActivity = 0;
for (int i = (seqList.Count - 1); i >= 0; i--)
{
if (seqList[i].ExecutionStatus == ActivityExecutionStatus.Closed)
{
//Check whether this is last child?
if (i == (seqList.Count - 1))
return false;
indexOfNextActivity = i + 1;
break;
}
}
seqList[indexOfNextActivity].RegisterForStatusChange(Activity.ClosedEvent, this);
executionContext.ExecuteActivity(seqList[indexOfNextActivity]);
this.SetValue(ActiveChildQualifiedNameProperty, seqList[indexOfNextActivity].QualifiedName);
return true;
}
protected virtual void OnSequenceComplete(ActivityExecutionContext executionContext)
{
if (executionContext == null)
throw new ArgumentNullException("executionContext");
this.RemoveProperty(ActiveChildQualifiedNameProperty);
}
#endregion
#region Dynamic Update Handler
protected override void OnActivityChangeRemove(ActivityExecutionContext executionContext, Activity removedActivity)
{
String activeChildQualifiedName = this.GetValue(ActiveChildQualifiedNameProperty) as String;
if (removedActivity.QualifiedName.Equals(activeChildQualifiedName))
activeChildRemovedInDynamicUpdate = true;
base.OnActivityChangeRemove(executionContext, removedActivity);
}
protected override void OnWorkflowChangesCompleted(ActivityExecutionContext executionContext)
{
String activeChildQualifiedName = this.GetValue(ActiveChildQualifiedNameProperty) as String;
if (activeChildQualifiedName != null && activeChildRemovedInDynamicUpdate)
{ //We have our active child removed.
if (this.ExecutionStatus == ActivityExecutionStatus.Canceling ||
(this.ExecutionStatus == ActivityExecutionStatus.Faulting) &&
(bool)this.GetValue(SequenceFaultingProperty))
{
if (this.ExecutionStatus == ActivityExecutionStatus.Faulting)
this.RemoveProperty(SequenceFaultingProperty);
this.RemoveProperty(ActiveChildQualifiedNameProperty);
executionContext.CloseActivity();
}
else if (this.ExecutionStatus == ActivityExecutionStatus.Executing)
{
if (!TryScheduleNextChild(executionContext))
{
OnSequenceComplete(executionContext);
executionContext.CloseActivity();
}
}
}
activeChildRemovedInDynamicUpdate = false;
base.OnWorkflowChangesCompleted(executionContext);
}
#endregion
}
}
|
