delphi - 将 TPopupMenu 对齐到表单的右侧？

Question

TPopupMenu 如何与表单的右侧对齐？问题是似乎没有办法在调用之前获取 Popup 菜单的宽度Popup(X, Y: Integer)。

我试图获得类似于 Chrome 中系统菜单的行为。

Answer 1

最简单的解决方案是自己启动弹出菜单：

procedure TForm1.Panel1ContextPopup(Sender: TObject; MousePos: TPoint;
  var Handled: Boolean);
var
  PopupPt: TPoint;
begin
  PopupPt := ClientToScreen(Point(ClientWidth, 0));
  TrackPopupMenu(PopupMenu1.Handle, TPM_RIGHTALIGN or TPM_TOPALIGN,
      PopupPt.X, PopupPt.Y, 0, PopupList.Window, nil);
end;

请参阅文档以了解各种标志的含义TrackPopupMenu或TrackPopupMenuEx含义。

Answer 2

您也可以设置Alignment为paRight并调用

with ClientToScreen(Point(ClientWidth - 1, 0)) do
  Popup(X, Y);