Index: ActiviteitenOpvolging/ActiviteitenOpvolging/screens/employee/details/EmployeeDetailUserControl.vb
===================================================================
diff -u -r1721 -r1723
--- ActiviteitenOpvolging/ActiviteitenOpvolging/screens/employee/details/EmployeeDetailUserControl.vb	(.../EmployeeDetailUserControl.vb)	(revision 1721)
+++ ActiviteitenOpvolging/ActiviteitenOpvolging/screens/employee/details/EmployeeDetailUserControl.vb	(.../EmployeeDetailUserControl.vb)	(revision 1723)
@@ -46,7 +46,7 @@
     ''' <inheritdoc/>
     Public Function RefreshData() As Boolean Implements IEmployeeDetailUserControl.RefreshData
         Try
-            LoadEmployee
+            LoadEmployee()
             Return True
         Catch ex As Exception
             Return False
Index: ActiviteitenOpvolging/ActiviteitenOpvolging/ActiviteitenOpvolgingForm.vb
===================================================================
diff -u -r1721 -r1723
--- ActiviteitenOpvolging/ActiviteitenOpvolging/ActiviteitenOpvolgingForm.vb	(.../ActiviteitenOpvolgingForm.vb)	(revision 1721)
+++ ActiviteitenOpvolging/ActiviteitenOpvolging/ActiviteitenOpvolgingForm.vb	(.../ActiviteitenOpvolgingForm.vb)	(revision 1723)
@@ -143,12 +143,17 @@
 
     ''' <inheritdoc/>
     Public Sub SelectEmployee(employeeIndex As Integer, employee As IEmployee) Implements IEmployeesMainForm.SelectEmployee
+        'Call function in dc.
         _domainController.SelectEmployee(employeeIndex, employee)
+        'Update all employee user controls.
+        _employeeUserControls.ForEach(Sub(employeeUserControl) employeeUserControl.RefreshData())
     End Sub
 
     ''' <inheritdoc/>
     Public Sub DeselectEmployee(employeeIndex As Integer) Implements IEmployeesMainForm.DeselectEmployee
         _domainController.DeselectEmployee(employeeIndex)
+        'Update all employee user controls.
+        _employeeUserControls.ForEach(Sub(employeeUserControl) employeeUserControl.RefreshData())
     End Sub
 
     ''' <inheritdoc/>
Index: ActiviteitenOpvolging/ActiviteitenOpvolging/domain/managers/implementations/EmployeeManager.vb
===================================================================
diff -u -r1721 -r1723
--- ActiviteitenOpvolging/ActiviteitenOpvolging/domain/managers/implementations/EmployeeManager.vb	(.../EmployeeManager.vb)	(revision 1721)
+++ ActiviteitenOpvolging/ActiviteitenOpvolging/domain/managers/implementations/EmployeeManager.vb	(.../EmployeeManager.vb)	(revision 1723)
@@ -17,7 +17,7 @@
             'Select the employees from the collection of all employees, which are not selected yet.
             'The employees are compared on their initials in lowercase.
             Return New HashSet(Of IEmployee)(_employees.Where(Function(employee) _
-                                                                 Not _selectedEmployeesDictionary.Any(Function(selectedEmployee) _
+                                                                 Not _selectedEmployeesDictionary.Values.Any(Function(selectedEmployee) _
                                                                                                employee.Equals(selectedEmployee))))
         End Get
     End Property
Index: ActiviteitenOpvolging/ActiviteitenOpvolging/screens/employee/EmployeeUserControl.vb
===================================================================
diff -u -r1721 -r1723
--- ActiviteitenOpvolging/ActiviteitenOpvolging/screens/employee/EmployeeUserControl.vb	(.../EmployeeUserControl.vb)	(revision 1721)
+++ ActiviteitenOpvolging/ActiviteitenOpvolging/screens/employee/EmployeeUserControl.vb	(.../EmployeeUserControl.vb)	(revision 1723)
@@ -4,6 +4,8 @@
     Implements IEmployeeUserControl, IEmployeeDetailParentUserControl, IEmployeePickerParentUserControl
 
     Private ReadOnly _parentForm As IEmployeesMainForm
+    Private _currentUserControl As IRefreshableUserControl
+
     Private ReadOnly Property EmployeeIndex As Integer
 
     Private Sub New()
@@ -62,8 +64,8 @@
     ''' <inheritdoc/>
     Public Function RefreshData() As Boolean Implements IEmployeeUserControl.RefreshData
         Try
-            'todo Call helper method.
-
+            'Refresh the data on the current user control.
+            _currentUserControl.RefreshData()
             'Refresh succesfull.
             Return True
         Catch ex As Exception
@@ -131,7 +133,9 @@
     ''' Swtich to another user control on the screen.
     ''' </summary>
     ''' <param name="userControl"></param>
-    Private Sub SwitchUserControl(userControl As UserControl)
+    Private Sub SwitchUserControl(Of T As {IRefreshableUserControl, UserControl})(userControl As T)
+        'Set current user control.
+        _currentUserControl = userControl
         'Remove the current user control from the screen.
         UserControlPanel.Controls.Clear()
         'Set the properties of the user control.
Index: ActiviteitenOpvolging/ActiviteitenOpvolging/screens/DataGridViewUserControl.vb
===================================================================
diff -u -r1721 -r1723
--- ActiviteitenOpvolging/ActiviteitenOpvolging/screens/DataGridViewUserControl.vb	(.../DataGridViewUserControl.vb)	(revision 1721)
+++ ActiviteitenOpvolging/ActiviteitenOpvolging/screens/DataGridViewUserControl.vb	(.../DataGridViewUserControl.vb)	(revision 1723)
@@ -100,22 +100,22 @@
         End Try
     End Sub
 
-    Private isInitialLoad As Boolean = True
+    Private _isInitialLoad As Boolean = True
     ''' <summary>
     ''' Fetch the data and fill the data grid view with it.
     ''' </summary>
     Private Sub LoadGrid()
         'Load all work items.
         LoadWorkItems()
 
-        If isInitialLoad Then
+        If _isInitialLoad Then
             'Update headers and visibility of static columns. This only happens once.
             UpdateStaticColumns()
 
             'Generate grid columns for the activities of the work items. This only happens once.
             GenerateActivityColumns(_workItems)
 
-            isInitialLoad = False
+            _isInitialLoad = False
         End If
 
         'Clear grid.