使 PopupMenu 出现在 VB6 中 TreeView 的选定项上

Question

我在VB6中有一个TreeView，当右键单击节点时，它使用PopupMenu。由于 VB6 PopupMenu 默认其位置为鼠标坐标，因此菜单出现在正确的位置。

我想要完成的是，当选择 TreeView 节点时，Popupmenu 也会出现在 KeyDown 事件的正确位置。我该怎么做？

Answer 1

您需要获取该项目的坐标。为此，您需要首先获取其句柄。当你得到矩形时，你必须将它转换为坐标。

Private Declare Function SendMessage Lib "user32.dll" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByRef lParam As Any) As Long
Private Declare Function MapWindowPoints Lib "user32.dll" (ByVal hwndFrom As Long, ByVal hwndTo As Long, ByRef lppt As Any, ByVal cPoints As Long) As Long

Private Type RECT
  Left As Long
  Top As Long
  Right As Long
  Bottom As Long
End Type

Private Type RECTF
  Left As Single
  Top As Single
  Right As Single
  Bottom As Single
End Type

Private Const TV_FIRST As Long = &H1100&
Private Const TVM_GETITEMRECT As Long = (TV_FIRST + 4)
Private Const TVM_GETNEXTITEM As Long = (TV_FIRST + 10)
Private Const TVGN_CARET As Long = &H9&


Private Function GetSelectedItemRect(ByVal tv As TreeView, ByRef outRect As RECTF) As Boolean
  Dim hItem As Long
  hItem = SendMessage(tv.hwnd, TVM_GETNEXTITEM, TVGN_CARET, ByVal 0&)

  If hItem Then
    Dim r As RECT
    r.Left = hItem

    If SendMessage(tv.hwnd, TVM_GETITEMRECT, 1, r) Then
      MapWindowPoints tv.hwnd, Me.hwnd, r, 2

      outRect.Left = Me.ScaleX(r.Left, vbPixels, Me.ScaleMode)
      outRect.Top = Me.ScaleY(r.Top, vbPixels, Me.ScaleMode)
      outRect.Right = Me.ScaleX(r.Right, vbPixels, Me.ScaleMode)
      outRect.Bottom = Me.ScaleY(r.Bottom, vbPixels, Me.ScaleMode)

      GetSelectedItemRect = True
    End If
  End If

End Function

用法：

Dim r As RECT

If GetSelectedItemRect(TreeView1, r) Then
  PopupMenu whatever, , r.Right, r.Top
End If