by Steve Gillham (1 Submission)
Category: Files/File Controls/Input/Output
Compatability: Visual Basic 5.0
Difficulty: Advanced
Date Added: Wed 3rd February 2021
Rating: 
(5 Votes)
Will check the parent node of a Treeview control when all of its child nodes are checked. will uncheck parent node when any one of it's child nodes are unchecked
Assumes
Assumes: Treeview control named TreeView1
Side Effects
none that I am aware of
VBcoders'==================================='
' This code has been provided for '
' use as FREEWARE - you may edit '
' or change any part of it for your '
' own needs. But please give credit'
' to myself, and do not sell this '
' unmodified code '
' By Steve Gillham '
'==================================='
Private Sub TreeView1_NodeCheck(ByVal node As MSComctlLib.node)
Call CheckChild(TreeView1, node) 'perform check on child nodes
End Sub
Private Sub CheckChild(Tree As TreeView, CurrentNode As node)
Dim ParentIndex 'used to find out the index of the parent node from the child node that was clicked
Dim CheckChecked As Integer 'Used to decide whether or not parent is to be checked
Dim j As Integer 'Counter
'This code works by finding the parent node of the node
'that you clicked on and then looking to see if all of
'the other same level nodes (as the one you clicked)
'are checked. If so it then checks the parent node and Vice Versa
If CurrentNode.Checked = True Then 'If node is checked then check parent node ONLY if ALL child nodes are checked
If Tree.Nodes.Item(CurrentNode.Index).Checked = True Then 'If "My Node"(My Node's Index) is checked then
ParentIndex = Tree.Nodes.Item(CurrentNode.Index).Parent.Index 'locate index of parent node
For j = 1 To Tree.Nodes.Item(ParentIndex).Children 'run loop to find out which child nodes
If Tree.Nodes.Item(ParentIndex + j).Checked = False Then 'are checked and which are not...
Me.BackColor = vbRed 'Store value of check/uncheck as 0 for
CheckChecked = CheckChecked + 0 'unchecked and 1 for checked, add to
ElseIf Tree.Nodes.Item(ParentIndex + j).Checked = True Then 'previous value
Me.BackColor = vbGreen
CheckChecked = CheckChecked + 1
End If
Next j
If CheckChecked = Tree.Nodes.Item(ParentIndex).Children Then 'if the number of checked nodes is equal
Tree.Nodes.Item(ParentIndex).Checked = True 'to number of child nodes then all child
Else 'nodes are checked so check parent node
Tree.Nodes.Item(ParentIndex).Checked = False
End If
End If
ElseIf CurrentNode.Checked = False Then 'if the current node is unchecked then
ParentIndex = Tree.Nodes.Item(CurrentNode.Index).Parent.Index 'uncheck the parent node as ALL child nodes
Tree.Nodes.Item(ParentIndex).Checked = False 'must be checked to before the parent node is checked
End If
End Sub
