OnBeginLabelEdit - AbstractTreeView

Fired just prior to the user starting in-line editing of an item label

Type: Event

Parameters

Parameter	Type	Description
hItem	Handle	Item handle
ByRef bCancel	Boolean	Can be used to cancel the event by returning True

Syntax

Procedure OnBeginLabelEdit Handle hItem ByRef Boolean bCancel

Description

If a user performs in-line editing of the label (TreeEditLabelsState must be True), the OnBeginLabelEdit event will be fired just prior to the user starting the editing.

The existing label value can be obtained by calling ItemLabel.

Sample

Procedure OnBeginLabelEdit Handle hItem Boolean ByRef bCancel
    Handle hRoot

    // if user is editing the root, don't allow and declare an error
    Get RootItem to hRoot
    If (hItem=hRoot) Begin
        Error DFERR_OPERATOR "Cannot change the root Label"
        Move True to bCancel
    End
End_Procedure

Procedure OnEndLabelEdit Handle hItem String sNewLabel Boolean bWasCanceled Boolean ByRef bCancel
    String sOriginalLabel

    If (not(bWasCanceled)) Begin
        // get old value of the label
        Get ItemLabel hItem to sOriginalLabel
        // don't allow edit to be blank 
        If (sNewLabel="") Begin
            Error DFERR_OPERATOR "Blank labels not allowed"
            Move True to bCancel
        End
        Else If (sOriginalLabel=sNewLabel) Begin
            // if no change, complain
            Error DFERR_OPERATOR "You did not change anything"
        End
    End
    Else Begin
        // This really isn't an error, but you get the idea
        Error DFERR_OPERATOR "Cancelled by User"
    End    
End_Procedure

Sample

This sample demonstrates the use of the bCancel parameter to cancel the editing of a TreeView item label.

Procedure OnBeginLabelEdit Handle hItem Boolean ByRef bCancel
    Move True to bCancel
End_Procedure