GanttControl.DependencySource Property

Gets or sets the data source that contains values that specify dependencies between tasks.

Namespace: DevExpress.XtraGantt

Assembly: DevExpress.XtraGantt.v20.1.dll

NuGet Package: DevExpress.Win.Gantt

Declaration

C#

[DXCategory("Data")]
[DefaultValue(null)]
public object DependencySource { get; set; }

VB.NET

<DXCategory("Data")>
<DefaultValue(Nothing)>
Public Property DependencySource As Object

Property Value

Type	Default	Description
Object	*null*	An object that specifies a data source.

Remarks

The DataSource property allows you to bind the control to a data source. The KeyFieldName property specifies a task’s unique identifier (key). See the TreeList.KeyFieldName property for more information.

The ParentFieldName property specifies a parent task’s key. This field allows you to organize tasks in a tree. See the TreeList.ParentFieldName property for more information.

You can also use a task’s key to specify the task’s predecessor(s).

If you need finish-to-start dependencies only, use the PredecessorsFieldName property to specify the data field that contains predecessors’ keys. The data should be of the System.Collections.IEnumerable type. The enumerator should return key values of the same type as the key field. In particular, you can use the following types:

• IList — use this type to allow users to modify dependencies and save changes to the data source. The collection should not be read only.
• String — the string should contain keys separated by space, comma, or semicolon (‘ ‘, ‘,’ ‘;’).

If you need finish-to-start and other dependency types, use the PredecessorFieldName and SuccessorFieldName properties and a separate data source assigned to the DependencySource property. See Task Dependencies for more information.

Example

The code below shows how to specify tasks and dependencies.

C#

using DevExpress.XtraGantt;

ganttControl1.TreeListMappings.KeyFieldName = "ID";
ganttControl1.TreeListMappings.ParentFieldName = "ParentID";
ganttControl1.ChartMappings.TextFieldName = "Text";
ganttControl1.ChartMappings.StartDateFieldName = "StartDate";
ganttControl1.ChartMappings.FinishDateFieldName = "FinishDate";
ganttControl1.DataSource = GetTasks();

ganttControl1.DependencyMappings.PredecessorFieldName = "PredecessorID";
ganttControl1.DependencyMappings.SuccessorFieldName = "SuccessorID";
ganttControl1.DependencyMappings.TypeFieldName = "DependencyType";
ganttControl1.DependencyMappings.LagFieldName = "TimeLag";
ganttControl1.DependencySource = GetDependencies();

DataTable GetTasks() {
    DataTable table = new DataTable();
    DataColumn id = new DataColumn("ID", typeof(int));
    DataColumn parentId = new DataColumn("ParentID", typeof(int));
    DataColumn text = new DataColumn("Text", typeof(string));
    DataColumn start = new DataColumn("StartDate", typeof(DateTime));
    DataColumn finish = new DataColumn("FinishDate", typeof(DateTime));
    table.Columns.AddRange(new DataColumn[] { id, parentId, text, start, finish });
    table.Rows.Add(new object[] { 1, 0, "Task 1", DateTime.Now, DateTime.Now.AddDays(1) });
    table.Rows.Add(new object[] { 2, 0, "Task 2", DateTime.Now.AddDays(1), DateTime.Now.AddDays(2) });
    table.Rows.Add(new object[] { 3, 0, "Task 3", DateTime.Now.AddDays(2), DateTime.Now.AddDays(3) });
    return table;
}

    DataTable GetDependencies() {
    DataTable table = new DataTable();
    DataColumn predecessor = new DataColumn("PredecessorID", typeof(int));
    DataColumn successor = new DataColumn("SuccessorID", typeof(int));
    DataColumn dependencyType = new DataColumn("DependencyType", typeof(DevExpress.XtraGantt.DependencyType));
    DataColumn lag = new DataColumn("TimeLag", typeof(TimeSpan));
    table.Columns.AddRange(new DataColumn[] { predecessor, successor, dependencyType, lag });
    table.Rows.Add(new object[] { 1, 2, DependencyType.StartToFinish, new TimeSpan(12, 0, 0) });
    table.Rows.Add(new object[] { 2, 3, DependencyType.StartToStart, null });
    return table;
}

VB.NET

ganttControl1.TreeListMappings.KeyFieldName = "ID"
ganttControl1.TreeListMappings.ParentFieldName = "ParentID"
ganttControl1.ChartMappings.TextFieldName = "Text"
ganttControl1.ChartMappings.StartDateFieldName = "StartDate"
ganttControl1.ChartMappings.FinishDateFieldName = "FinishDate"
ganttControl1.DataSource = GetTasks()

ganttControl1.DependencyMappings.PredecessorFieldName = "PredecessorID"
ganttControl1.DependencyMappings.SuccessorFieldName = "SuccessorID"
ganttControl1.DependencyMappings.TypeFieldName = "DependencyType"
ganttControl1.DependencyMappings.LagFieldName = "TimeLag"
ganttControl1.DependencySource = GetDependencies()

Private Function GetTasks() As DataTable
    Dim table As New DataTable()
    Dim id As New DataColumn("ID", GetType(Integer))
    Dim parentId As New DataColumn("ParentID", GetType(Integer))
    Dim taskText As New DataColumn("Text", GetType(String))
    Dim start As New DataColumn("StartDate", GetType(DateTime))
    Dim finish As New DataColumn("FinishDate", GetType(DateTime))
    table.Columns.AddRange(New DataColumn() {id, parentId, taskText, start, finish})
    table.Rows.Add(New Object() { 1, 0, "Task 1", DateTime.Now, DateTime.Now.AddDays(1) })
    table.Rows.Add(New Object() { 2, 0, "Task 2", DateTime.Now.AddDays(1), DateTime.Now.AddDays(2) })
    table.Rows.Add(New Object() { 3, 0, "Task 3", DateTime.Now.AddDays(2), DateTime.Now.AddDays(3) })
    Return table
End Function

Private Function GetDependencies() As DataTable
    Dim table As New DataTable()
    Dim predecessor As New DataColumn("PredecessorID", GetType(Integer))
    Dim successor As New DataColumn("SuccessorID", GetType(Integer))
    Dim dependencyType As New DataColumn("DependencyType", GetType(DevExpress.XtraGantt.DependencyType))
    Dim lag As New DataColumn("TimeLag", GetType(TimeSpan))
    table.Columns.AddRange(New DataColumn() {predecessor, successor, dependencyType, lag})
    table.Rows.Add(New Object() {1, 2, DevExpress.XtraGantt.DependencyType.StartToFinish, New TimeSpan(12, 0, 0)})
    table.Rows.Add(New Object() {2, 3, DevExpress.XtraGantt.DependencyType.StartToStart, Nothing})
    Return table
End Function