event AllowAutoDrag (Item as HITEM, NewParent as HITEM, InsertA as HITEM, InsertB as HITEM, Cancel as Boolean)
Occurs when the user drags the item between InsertA and InsertB as child of NewParent.

 TypeDescription 
   Item as HITEM A long expression that specifies the handle of the item being dragged.  
   NewParent as HITEM A long expression that specifies the handle of the newly parent, to insert the dragging Item. If 0, it indicates root items. The ItemParent property indicates the currently parent of the item.  
   InsertA as HITEM A long expression that specifies the handle of the item to insert the dragging Item after. If 0, it indicates that no item after.  
   InsertB as HITEM A long expression that specifies the handle of the item to insert the dragging Item before. If 0, it indicates that no item before.  
   Cancel as Boolean A Boolean expression that specifies whether the operation can continue ( this parameter is by reference )  
The AllowAutoDrag event occurs when the user drags the item between InsertA and InsertB as child of NewParent, using the AutoDrag property. The AutoDrag feature indicates what the control does when the user clicks an item and starts dragging it. For instance, using the AutoDrag feature you can let the user arrange the items in the control, or can drop the selection to a any OLE compliant applications like Microsoft Word, Excel and so on... The AllowAutoDrag event may fire when the AutoDrag property is any of the following values:

You can use the AllowAutoDrag event to cancel or continue drag and drop operation using the AutoDrag property.

The following screen shot shows the NewParent, InsertA and InsertB parameters, when "Task 2" is dragging to a new position:

Syntax for AllowAutoDrag event, /NET version, on:

private void AllowAutoDrag(object sender,int   Item,int   NewParent,int   InsertA,int   InsertB,ref bool   Cancel)
{
}

Private Sub AllowAutoDrag(ByVal sender As System.Object,ByVal Item As Integer,ByVal NewParent As Integer,ByVal InsertA As Integer,ByVal InsertB As Integer,ByRef Cancel As Boolean) Handles AllowAutoDrag
End Sub

Syntax for AllowAutoDrag event, /COM version, on:

private void AllowAutoDrag(object sender, AxEXG2ANTTLib._IG2anttEvents_AllowAutoDragEvent e)
{
}

void OnAllowAutoDrag(long   Item,long   NewParent,long   InsertA,long   InsertB,BOOL FAR*   Cancel)
{
}

void __fastcall AllowAutoDrag(TObject *Sender,Exg2anttlib_tlb::HITEM   Item,Exg2anttlib_tlb::HITEM   NewParent,Exg2anttlib_tlb::HITEM   InsertA,Exg2anttlib_tlb::HITEM   InsertB,VARIANT_BOOL *   Cancel)
{
}

procedure AllowAutoDrag(ASender: TObject; Item : HITEM;NewParent : HITEM;InsertA : HITEM;InsertB : HITEM;var Cancel : WordBool);
begin
end;

procedure AllowAutoDrag(sender: System.Object; e: AxEXG2ANTTLib._IG2anttEvents_AllowAutoDragEvent);
begin
end;

begin event AllowAutoDrag(long  Item,long  NewParent,long  InsertA,long  InsertB,boolean  Cancel)

end event AllowAutoDrag

Private Sub AllowAutoDrag(ByVal sender As System.Object, ByVal e As AxEXG2ANTTLib._IG2anttEvents_AllowAutoDragEvent) Handles AllowAutoDrag
End Sub

Private Sub AllowAutoDrag(ByVal Item As EXG2ANTTLibCtl.HITEM,ByVal NewParent As EXG2ANTTLibCtl.HITEM,ByVal InsertA As EXG2ANTTLibCtl.HITEM,ByVal InsertB As EXG2ANTTLibCtl.HITEM,Cancel As Boolean)
End Sub

Private Sub AllowAutoDrag(ByVal Item As Long,ByVal NewParent As Long,ByVal InsertA As Long,ByVal InsertB As Long,Cancel As Boolean)
End Sub

LPARAMETERS Item,NewParent,InsertA,InsertB,Cancel

PROCEDURE OnAllowAutoDrag(oG2antt,Item,NewParent,InsertA,InsertB,Cancel)

RETURN

Syntax for AllowAutoDrag event, /COM version (others), on:

<SCRIPT EVENT="AllowAutoDrag(Item,NewParent,InsertA,InsertB,Cancel)" LANGUAGE="JScript">
</SCRIPT>

<SCRIPT LANGUAGE="VBScript">
Function AllowAutoDrag(Item,NewParent,InsertA,InsertB,Cancel)
End Function
</SCRIPT>

Procedure OnComAllowAutoDrag HITEM   llItem HITEM   llNewParent HITEM   llInsertA HITEM   llInsertB Boolean   llCancel
	Forward Send OnComAllowAutoDrag llItem llNewParent llInsertA llInsertB llCancel
End_Procedure

METHOD OCX_AllowAutoDrag(Item,NewParent,InsertA,InsertB,Cancel) CLASS MainDialog
RETURN NIL

void onEvent_AllowAutoDrag(int   _Item,int   _NewParent,int   _InsertA,int   _InsertB,COMVariant /*bool*/   _Cancel)
{
}

function AllowAutoDrag as v (Item  as  OLE::Exontrol.G2antt.1::HITEM,NewParent  as  OLE::Exontrol.G2antt.1::HITEM,InsertA  as  OLE::Exontrol.G2antt.1::HITEM,InsertB  as  OLE::Exontrol.G2antt.1::HITEM,Cancel  as  L)
end function

function nativeObject_AllowAutoDrag(Item,NewParent,InsertA,InsertB,Cancel)
return

The AllowDragDrop event triggers contiguously while the user drags / hovers the focus/selection of items over the control. The GetAsyncKeyState API method can be used to detect whether the mouse button has been released, and so the drop action occurs. 

The following VB sample displays "Drag" while user dragging the items, and displays "Drop", when drop operation starts.

Private Sub G2antt1_AllowAutoDrag(ByVal Item As EXG2ANTTLibCtl.HITEM, ByVal NewParent As EXG2ANTTLibCtl.HITEM, ByVal InsertA As EXG2ANTTLibCtl.HITEM, ByVal InsertB As EXG2ANTTLibCtl.HITEM, Cancel As Boolean)
    With G2antt1
        Debug.Print "Drag"
        If (GetAsyncKeyState(VK_LBUTTON) = 0) Then
            Debug.Print "Drop"
        End If
    End With
End Sub

where declarations for GetAsyncKeyState API used is:

Private Const VK_LBUTTON = &H1
Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Long) As Integer

Once you run the code, you will notice that the AllowAutoDrag event "Drop" may be fired multiple times, so we suggest to postpone any of your actions ( like displaying a message box ), by posting a window message or use a timer event, to let the control handles / completes the event as in the following sample:

Private Sub G2antt1_AllowAutoDrag(ByVal Item As EXG2ANTTLibCtl.HITEM, ByVal NewParent As EXG2ANTTLibCtl.HITEM, ByVal InsertA As EXG2ANTTLibCtl.HITEM, ByVal InsertB As EXG2ANTTLibCtl.HITEM, Cancel As Boolean)
    With G2antt1
        Debug.Print "Drag"
        If (GetAsyncKeyState(VK_LBUTTON) = 0) Then
            mctlTimerDrop.Enabled = True
        End If
    End With
End Sub

where mctlTimerDrop is defined as follows:

Dim WithEvents mctlTimerDrop As VB.Timer

Private Sub mctlTimerDrop_Timer()
    mctlTimerDrop.Enabled = False
    MsgBox "Drop."
End Sub


Private Sub Form_Load()
    Set mctlTimerDrop = Me.Controls.Add("VB.Timer", "DropTimer1")
    With mctlTimerDrop
        .Enabled = False
        .Interval = 100
    End With
End Sub


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