*TreeView*

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Overview (TreeView)
Action (TreeView)
AddExistingNode (TreeView)
AfterSelect Event (TreeView)
AddImage1 (TreeView)
AddImage2 (TreeView)
AddNewNode (TreeView)
CheckBoxes (TreeView)
CollapseAll (TreeView)
Color (TreeView)
Control (TreeView)
Count (TreeView)
Enabled (TreeView)
ExpandAll P(TreeView)
FontColor (TreeView)
GetNode (TreeView)
Height (TreeView)
ImageIndex (TreeView)
ImageMode (TreeView)
ImageSize (TreeView)
Indent (TreeView)
IndexOfNode (TreeView)
InsertNode (TreeView)
Left (TreeView)
New1 (TreeView)
RemoveAllNodes (TreeView)
RemoveNode (TreeView)
RemoveNodeAt (TreeView)
SelectedImageIndex (TreeView)
SelectedNode (TreeView)
SelectedText (TreeView)
ShowLines (TreeView)
ShowPlusMinus (TreeView)
ShowRootLines (TreeView)
Top (TreeView)
Width (TreeView)
Visible (TreeView)
AddNewNode (TreeView - Node)
Checked (TreeView - Node)
Collapse (TreeView - Node)
Count (TreeView - Node)
CreateNew (TreeView - Node)
Expand (TreeView - Node)
ExpandAll (TreeView - Node)
GetNode (TreeView - Node)
ImageIndex (TreeView - Node)
IndexOfNode (TreeView - Node)
InsertNode (TreeView - Node)
IsRoot (TreeView - Node)
New1 (TreeView - Node)
Parent (TreeView - Node)
RemoveAllNodes (TreeView - Node)
RemoveNode (TreeView - Node)
RemoveNodeAt (TreeView - Node)
SelectedImageIndex (TreeView - Node)
Text Previous (TreeView - Node)
Value (TreeView - Node)


Overview (TreeView) Top

TreeView objects display a hierarchical tree.
Each node in the tree is of Node type and can contain other nodes.
The TreeView can show small images left of the nodes.
Working with a TreeView is done using a TreeView object and one or more Node objects.
One Node object can be used to reference different nodes each time.
Nodes added directly to the TreeView will appear as the root nodes.
The other nodes are added to nodes.
When the user selects a node the AfterSelect event is raised.
The SelectedNode property stores a reference to the selected node.
The TreeView can show a checkbox for each node.

Example:
'Add a TreeView named tv and two Nodes named node1 and node2.
Sub Globals

End Sub

Sub App_Start
Form1.Show
tv.New1("Form1", 5, 10, 200, 200)
node1.New1
node2.New1
node1.Value = tv.AddNewNode("Parent") 'node1 references the newly created node
for i = 1 to 5
node1.AddNewNode("Child" & i)
next
node2.Value = node1.GetNode(2) 'node2 references Child3
for i = 1 to 3
node2.AddNewNode("GrandChildren" & i)
next
node1.Value = node2.GetNode (0) 'node1 references GrandChildren1
node1.AddNewNode ("Great-Grandson")
tv.ExpandAll
End Sub

Sub tv_AfterSelect
'The commented statement does the same thing as the two following lines.
'Form1.Text = tv.SelectedText
node1.Value = tv.SelectedNode
Form1.Text = node1.Text
End Sub


Action (TreeView) Top

Gets a string that specifies the cause for the last AfterSelect event.
Syntax: Action
The possible values are:
bykeyboard
bymouse
collapse
expand
unknown

Example:
Sub tv_AfterSelect
if tv.Action = "bymouse" then ...
End Sub


AddExistingNode (TreeView) Top

Adds an existing node to the TreeView object.
Syntax: AddExistingNode (treeNode As Node)

Example:
tv.AddExistingNode (node1.Value)


AfterSelect Event (TreeView) Top

Occurs when the selected node has changed.
To find the exact cause that raised this event, you can check the Action property value.
Example:
Sub tv_AfterSelect
if tv.Action = "bymouse" then ...
End Sub


AddImage1 (TreeView) Top

Adds an image to the list of images of the TreeView object.
The first image added gets the index 0.
Syntax: AddImage1 (file As String)

Example:
tv.AddImage1 (AppPath & "\smiley.gif")


AddImage2 (TreeView) Top

Adds an image to the list of images of the TreeView object.
The first image added gets the index 0.
Syntax: AddImage2 (image As Image)

Example:
tv.AddImage2 (ImageList1.Item(0))


AddNewNode (TreeView) Top

Creates a new node, adds it to the TreeView object and returns a reference to it.
Syntax: AddNewNode (text As String) As Node

Example:
Form1.Show
tv.New1("Form1", 5, 10, 200, 200)
node1.New1
node1.Value = tv.AddNewNode("Parent") 'node1 references the newly created node


CheckBoxes (TreeView) Top

Gets or sets whether to show a checkbox left of each node in the TreeView object.
Syntax: CheckBoxes

Example:
tv.CheckBoxes = true


CollapseAll (TreeView) Top

Causes all nodes to collapse.
Syntax: CollapseAll

Example:
tv.CollapseAll


Color (TreeView) Top

Gets or sets the color of the control.
Syntax: Color


Control (TreeView) Top

Returns a reference to the Treeview object.
Syntax: Control


Count (TreeView) Top

Returns the number of nodes that belong to the TreeView object (only the root nodes).
Syntax: Count


Enabled (TreeView) Top

Gets or sets whether the control is enabled.
Syntax: Enabled


ExpandAll P(TreeView) Top

Causes all nodes to expand.
Syntax: ExapndAll

Example:
tv.ExpandAll


FontColor (TreeView) Top

Gets or sets the color of the font.
Syntax: FontColor


GetNode (TreeView) Top

Returns a reference to a node in the TreeView object.
Syntax:GetNode (index As Int32) As Node
The index of the first node in the TreeView is 0.

Example:
node1.Value = tv.GetNode (0)


Height (TreeView) Top

Gets or sets the height of the control.
Syntax: Height


ImageIndex (TreeView) Top

Gets or sets the default image displayed for all the nodes.
Syntax: ImageIndex

Example:
tv.ImageSize(30,30)
tv.ImageMode = true
tv.AddImage1(AppPath & "\smiley.gif")
tv.AddImage1(AppPath & "\pic.jpg")
tv.ImageIndex = 0 'smiley.gif
tv.SelectedImageIndex = 1 'pic.jpg


ImageMode (TreeView) Top

Gets or sets whether to show images left of the nodes.
Syntax: ImageMode

Example:
tv.ImageSize(30,30)
tv.ImageMode = true
tv.AddImage1(AppPath & "\smiley.gif")
tv.AddImage1(AppPath & "\pic.jpg")
tv.ImageIndex = 0 'smiley.gif
tv.SelectedImageIndex = 1 'pic.jpg


ImageSize (TreeView) Top

Sets the size of the images shown.
Syntax: ImageSize (width As Int32, height As Int32)

Example:
tv.ImageSize(30,30)
tv.ImageMode = true
tv.AddImage1(AppPath & "\smiley.gif")
tv.AddImage1(AppPath & "\pic.jpg")
tv.ImageIndex = 0 'smiley.gif
tv.SelectedImageIndex = 1 'pic.jpg


Indent (TreeView) Top

Gets or sets the indent size between different levels in the TreeView object.
Syntax: Indent


IndexOfNode (TreeView) Top

Gets the index of a node in the TreeView.
Returns -1 if the node does not exist.
Syntax: IndexOfNode (treeNode As Node) As Int 32

Example:
if tv.IndexOfNode (node1.Value) = -1 then ...



InsertNode (TreeView) Top

Inserts a node in the specified index.
Syntax: InsertNode (index As Int32, node As Node)
index - The node will be inserted in this index.

Example:
tv.InsertNode (2, node1.Value)


Left (TreeView) Top

Gets or sets the Left property of the control.
Syntax: Left


New1 (TreeView) Top

Initializes the TreeView object and adds it to a form or a panel.
Syntax: New1 (FormName As Control, left As Int32 , top As Int32, width As Int32, height As Int32)

Example:
tv.New1("Form1", 5, 10, 200, 200)


RemoveAllNodes (TreeView) Top

Removes all nodes from the TreeView object.
Syntax: RemoveAllNodes

Example:
tv.RemoveAllNodes


RemoveNode (TreeView) Top

Removes a specific node from the TreeView.
Syntax: RemoveNode (node As Node)

Example:
tv.RemoveNode (node1.Value)


RemoveNodeAt (TreeView) Top

Removes a specific node from the TreeView object.
Syntax: RemoveNodeAt (index As Int32)

Example:
tv.RemoveNodeAt (0) 'Removes the first node


SelectedImageIndex (TreeView) Top

Gets or sets the default image displayed when a node is selected.
Syntax: SelectedImageIndex

Example:
tv.ImageSize(30,30)
tv.ImageMode = true
tv.AddImage1(AppPath & "\smiley.gif")
tv.AddImage1(AppPath & "\pic.jpg")
tv.ImageIndex = 0 'smiley.gif
tv.SelectedImageIndex = 1 'pic.jpg


SelectedNode (TreeView) Top

Gets or sets the selected node.
Syntax: SelectedNode

Example:
Sub tv_AfterSelect
node1.Value = tv.SelectedNode
Form1.Text = node1.Text
End Sub


SelectedText (TreeView) Top

Gets the text of the selected node.
Syntax: SelectedText


ShowLines (TreeView) Top

Gets or sets whether lines will appear between the nodes.
Syntax: ShowLines

Example:
tv.ShowLines = true


ShowPlusMinus (TreeView) Top

Gets or sets whether the small plus signs will appear left of the nodes.
Syntax: ShowPlusMinus

Example:
tv.ShowPlusMinus = true


ShowRootLines (TreeView) Top

Gets or sets whether lines will appear before the root nodes.
Syntax: ShowRootLines

Example:
tv.ShowRootLines = false


Top (TreeView) Top

Gets or sets the Top property of the control.
Syntax: Top


Width (TreeView) Top

Gets or sets the width of the control.
Syntax: Width


Visible (TreeView) Top

Gets or sets whether the control is visible.
Syntax: Visible


AddExistingNode (TreeView - Node)
Adds an existing node to the node.
Syntax: AddExistingNode (treeNode As Node)

Example:
node1.AddExistingNode (node2.Value)


AddNewNode (TreeView - Node) Top

Creates a new node, adds it to the current node and returns a reference to it.
Syntax: AddNewNode (text As String) As Node

Example:
node2.Value = node1.AddNewNode("folder")


Checked (TreeView - Node) Top

Gets or sets whether the node is checked.
Syntax: Checked

Example:
node1.Checked = true


Collapse (TreeView - Node) Top

Causes the current node to collapse.
Syntax: Collapse

Example:
node1.Collapse


Count (TreeView - Node) Top

Returns the number of nodes the current node contains.
Syntax: Count

Example:
for i = 0 to node2.Count-1
node1.Value = node2.GetNode(i)
node1.Checked = true
next


CreateNew (TreeView - Node) Top

Creates a new node.
Syntax: CreateNew (text As String)

Example:
node1.New1
node1.CreateNew ("some text")


Expand (TreeView - Node) Top

Expands the current node.
Syntax: Expand

Example:
node1.Expand


ExpandAll (TreeView - Node) Top

Expands all nodes under the current node.
Syntax: ExpandAll

Example:
node1.ExpandAll


GetNode (TreeView - Node) Top

Gets a reference to a node that belongs to the current node.
Syntax: GetNode (index As Int32) As Node

Example:
node2.Value = node1.GetNode (0)


ImageIndex (TreeView - Node) Top

Gets or sets the image of the current node.
Syntax: ImageIndex

Example:
node1.ImageIndex = 2 'The third image added to the TreeView


IndexOfNode (TreeView - Node) Top

Returns the index of the specified node in the current node.
If the node does not belong to the current node, it will return -1.
Syntax: IndexOfNode (node As Node) As Int32

Example:
i = node1.IndexOfNode (node2.Value)


InsertNode (TreeView - Node) Top

Inserts an existing node into the current node.
Syntax: InsertNode (index As Int32, node As Node)

Example:
node1.InsertNode (4, node2.Value)


IsRoot (TreeView - Node) Top

Checks whether the current node belongs directly to the TreeView object.
Syntax: IsRoot

Example:
If node1.IsRoot = false then node2.Value = node1.Parent


New1 (TreeView - Node) Top

Initializes the object.
Syntax: New1

Example:
node1.New1


Parent (TreeView - Node) Top

Returns a reference to the node's parent.
Syntax: Parent

Example:
If node1.IsRoot = false then node2.Value = node1.Parent


RemoveAllNodes (TreeView - Node) Top

Removes all nodes that belong to the current node.
Syntax: RemoveAllNodes

Example:
node1.RemoveAllNodes


RemoveNode (TreeView - Node) Top

Removes a specific node from the current node.
Syntax: RemoveNode (node As Node)

Example:
node1.RemoveNode (node2.Value)


RemoveNodeAt (TreeView - Node) Top

Removes a specific node from the current node.
Syntax: RemoveNodeAt (index As Int32)
index - The index of the node that will be removed.

Example:
node1.RemoveNodeAt (0) 'Removes the first node


SelectedImageIndex (TreeView - Node) Top

Gets or sets the image that will be displayed when the node is selected.
Syntax: SelectedImageIndex

Example:
node1.SelectedImage = 0


Text Previous (TreeView - Node) Top

Gets or sets the text of the node.
Syntax: Text

Example:
node1.Text = "new"


Value (TreeView - Node) Top

Gets or sets the node that this node references to.
Syntax: Value

Example:
node1.Value = tv.AddNewNode("abc")