3.06 上下文菜单

显示上下文菜单

BOOL TrackPopupMenu(
  HMENU hMenu, //菜单句柄UINT
  uFlags, //显示方式intX, //水平位置,屏幕坐标系
  inty, //垂直位置,屏幕坐标系
  int nReserved, //保留,必须0
  HWND hWnd, //处理菜单消息的窗口句柄
  CONST RECT*prcRect //NULL,忽略
); TrackPopupMenu是阻塞函数

在 WM_RBUTTONUP 构建

void OnRButtonUp(HWND hWnd, LPARAM lParam) {
  HMENU hMain = LoadMenu(GetModuleHandle(NULL), (char*)IDR_MENU1);  // 获取菜单句柄
  HMENU hPopup = GetSubMenu(hMain,0); // 获取第一个子菜单
  // 获取屏幕坐标
  POINT pt;
  pt.x = LOWORD(lParam);
  pt.y = HIWORD(lParam);
  ClientToScreen(hWnd, &pt);
  // 构建菜单
  TrackPopupMenu(
      hPopup,
      TPM_CENTERALIGN | TPM_VCENTERALIGN,
      pt.x, pt.y,
      0,
      hWnd,
      NULL
 );
}

在 WM_CONTEXTMENU 构建

• WParam：右键点击的窗口句柄
• lParam:
  • LOWORD X 坐标，屏幕坐标系
  • HIWORD Y 坐标，屏幕坐标系

WM_CONTEXTMENU 消息是在 WM_RBUTTONUP 消息之后产生。

void OnContextMenu(HWND hWnd, LPARAM lParam) {
  HMENU hMain = LoadMenu(GetModuleHandle(NULL), (char*)IDR_MENU1);  // 获取菜单句柄
  HMENU hPopup = GetSubMenu(hMain,0); // 获取第一个子菜单
  TrackPopupMenu(
      hPopup,
      TPM_CENTERALIGN | TPM_VCENTERALIGN,
      LOWORD(lParam), HIWORD(lParam),
      0,
      hWnd,
      NULL
 );
}