B4J Question How? Correct crossplatform mouse object moving (dragging) by _Touch event

Private Sub mRoot_Touch (Action As Int, X As Float, Y As Float)
    If Action = mRoot.TOUCH_ACTION_DOWN Then
        Dragging = True
        DownX = X
        DownY = Y
    Else If Action = mRoot.TOUCH_ACTION_UP Then
        Dragging = False
    Else If Dragging And Action = mRoot.TOUCH_ACTION_MOVE Then
        'If mRoot.Left + mRoot.Width <= mParent.Width Then
        mRoot.Left = mRoot.Left + X - DownX
        mRoot.Top = mRoot.Top + Y - DownY
    End If
End Sub

Private Sub Panel1_Touch (o As Object, ACTION As Int, x As Float, y As Float, motion As Object) As Boolean

    #if B4A
    Dim r As Reflector
    r.Target = mRoot
    r.SetOnTouchListener("mRoot_Touch")
    #end if
End Sub


#if B4A
Private Sub mRoot_Touch (o As Object, ACTION As Int, x As Float, y As Float, motion As Object) As Boolean
#else
Private Sub mRoot_Touch (Action As Int, X As Float, Y As Float)
#end if
    If Action = mRoot.TOUCH_ACTION_DOWN Then
        Dragging = True
        DownX = X
        DownY = Y
    Else If Action = mRoot.TOUCH_ACTION_UP Then
        Dragging = False
    Else If Dragging And Action = mRoot.TOUCH_ACTION_MOVE Then
        'If mRoot.Left + mRoot.Width <= mParent.Width Then
        mRoot.Left = mRoot.Left + X - DownX
        mRoot.Top = mRoot.Top + Y - DownY
    End If
    #if B4A
    Return True
    #end if
End Sub

Sub Class_Globals
...
    Private DownX, DownY As Double, Dragging As Boolean, DraggingStart As Long
    Private GridSize As Int = 5dip
End Sub

#if B4A
Private Sub mRoot_Touch (o As Object, ACTION As Int, x As Float, y As Float, motion As Object) As Boolean
#else
Private Sub mRoot_Touch (Action As Int, X As Float, Y As Float)
#end if
    If Action = mRoot.TOUCH_ACTION_DOWN Then
        Dragging = True
        DraggingStart = DateTime.Now
        DownX = X
        DownY = Y
    Else If Action = mRoot.TOUCH_ACTION_UP Then
        Dragging = False
        #if B4A
            If (DateTime.Now - DraggingStart) > 500 Then
                mRoot_LongClick
            Else
                mRoot_Click
            End If
        #end if
    Else If Dragging And Action = mRoot.TOUCH_ACTION_MOVE Then
        mRoot.Left = Max(0, Min(mRoot.Parent.Width - mRoot.Width, ApplyGrid(mRoot.Left + X - DownX)))
        mRoot.Top = Max(0, Min(mRoot.Parent.Height - mRoot.Height, ApplyGrid(mRoot.Top + Y - DownY)))
    End If
    #if B4A
    Return True
    #end if
End Sub

Private Sub ApplyGrid (x As Int) As Int
    If GridSize > 0 Then
        Return x - (x Mod GridSize)
    End If
    Return x
End Sub