不靠谱的tooltip

typedef struct tagTOOLINFOA {

    UINT cbSize;

    UINT uFlags;

    HWND hwnd;

    UINT_PTR uId;

    RECT rect;

    HINSTANCE hinst;

    LPSTR lpszText;

#if (_WIN32_IE >= 0x0300)

    LParaM lParam;

#endif

#if (_WIN32_WINNT >= 0x0501)

    void *lpReserved;

#endif

} TTTOOLINFOA,NEAR *PTOOLINFOA,*LPTTTOOLINFOA;

如果#define _WIN32_WINNT 0x0500，那么tooltip一切正常

当有一天#define _WIN32_WINNT 0x0501了，

这时设置tooltip.cbSize = sizeof(TOOLINFO)的时候就让人崩溃了。

编译调试不显示任何错误，但是tooltip就是显示不出来了。。。(they were just failing silently without kNowing why)

因为系统默认加载comctl 5.82，这个版本里面的tooltip的size根本没有sizeof(TOOLINFO),里面没有void *lpReserved;

所以cbSize设大了，出错了。。。

这时需要写成 tooltip.cbSize = TTTOOLINFOA_V2_SIZE;

或者强制指定comctl 6.0

#pragma comment(linker,"\"/manifestdependency:type='Win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='X86' publicKeyToken='6595b64144ccf1df' language='*'\"")

ps:  指定#define _WIN32_WINNT 0x0501将导致程序只能运行在xp及以上系统。

测试程序：

#define _WIN32_WINNT 0x0501

#define WINVER 0x0501

#include <windows.h>

#include <commctrl.h>

#include <stdio.h>

#pragma comment(lib,"user32.lib")

#pragma comment(lib,"comctl32.Lib")

#pragma comment(lib,"gdi32.Lib")

int count;

TCHAR str[1000];

HWND g_hwndTrackingTT;

TOOLINFO g_toolItem;

HINSTANCE g_hInst;

BOOL g_TrackingMouse = FALSE;

LRESULT CALLBACK WindowFunc(HWND,UINT,WParaM,LParaM);

HWND CreateTrackingToolTip(int toolID,HWND hDlg,char *pText);

TCHAR szWinName[] = TEXT("MyWin");

int WINAPI WinMain(HINSTANCE hThisInst,HINSTANCE hPrevInst,LPSTR lpszArgs,int nWinMode)

{

HWND hwnd;

MSG msg;

WNDCLASSEX wcl;

INITCOMMONCONTROLSEX ic;

BOOL ret;

g_hInst = hThisInst;

ic.dwSize = sizeof(INITCOMMONCONTROLSEX);

ic.dwICC = 0x00004000;//ICC_STANDARD_CLASSES|ICC_BAR_CLASSES;

ret = InitCommonControlsEx(&ic);

wcl.cbSize = sizeof(WNDCLASSEX);

wcl.hInstance = hThisInst;

wcl.lpszClassName = szWinName;

wcl.lpfnWndProc = WindowFunc;

wcl.style = CS_HREDRAW|CS_VREDRAW;

wcl.hIcon = LoadIcon(NULL,IDI_APPLICATION);

wcl.hIconSm = NULL;

wcl.hCursor = LoadCursor(NULL,IDC_ARROW);

wcl.lpszMenuName = NULL;

wcl.cbClsExtra = 0;

wcl.cbWndExtra = 0;

wcl.hbrBackground = (HBrush) GetStockObject(WHITE_Brush);

if(!RegisterClassEx(&wcl)) return 0;

hwnd = CreateWindowEx(

WS_EX_WINDOWEDGE,

szWinName,

TEXT("Window Title"),

WS_OVERLAPPEDWINDOW,

CW_USEDEFAULT,

HWND_DESKTOP,

NULL,

hThisInst,

NULL

);

ShowWindow(hwnd,nWinMode);

UpdateWindow(hwnd);

while(GetMessage(&msg,NULL,0))

{

TranslateMessage(&msg);

dispatchMessage(&msg);

}

return msg.wParam;

}

LRESULT CALLBACK WindowFunc(HWND hwnd,UINT message,WParaM

wParam,LParaM lParam)

{

HDC hdc;

PAINTSTRUCT ps;

static int cxClient = 0,cyClient = 0,oldX,oldY;

int newX,newY;

char coords[12];

POINT pt;

switch(message){

case WM_CREATE:

g_hwndTrackingTT = CreateTrackingToolTip(456,hwnd,"");

return 0;

case WM_SIZE:

cxClient = LOWORD(lParam);

cyClient = HIWORD(lParam);

return 0;

case WM_PAINT:

hdc = BeginPaint(hwnd,&ps);

EndPaint(hwnd,&ps);

return 0;

case WM_MOUSELEAVE:

// The mouse pointer has left our window.

// Deactivate the ToolTip.

SendMessage(g_hwndTrackingTT,TTM_TRACKACTIVATE,(WParaM)

FALSE,(LParaM)&g_toolItem);

g_TrackingMouse = FALSE;

return FALSE;

case WM_MOUSEMOVE:

if (!g_TrackingMouse)

// The mouse has just entered the window.

{

// Request notification when the mouse leaves.

TRACKMOUSEEVENT tme = { sizeof(TRACKMOUSEEVENT) };

tme.hwndTrack = hwnd;

tme.dwFlags = TME_LEAVE;

TrackMouseEvent(&tme);

// Activate the ToolTip.

SendMessage(g_hwndTrackingTT,

(WParaM)TRUE,(LParaM)&g_toolItem);

g_TrackingMouse = TRUE;

}

newX = LOWORD(lParam);

newY = HIWORD(lParam);

// Make sure the mouse has actually moved. The presence of the ToolTip

// causes Windows to send the message continuously.

if ((newX != oldX) || (newY != oldY))

{

oldX = newX;

oldY = newY;

// Update the text.

sprintf(coords,"%d,%d",newX,newY);

g_toolItem.lpszText = coords;

SendMessage(g_hwndTrackingTT,TTM_SETTOOLINFO,(LParaM)

&g_toolItem);

// Position the ToolTip.

// The coordinates are adjusted so that the ToolTip does not

// overlap the mouse pointer.

pt.x = newX;

pt.y = newY;

ClientToScreen(hwnd,&pt);

SendMessage(g_hwndTrackingTT,TTM_TRACKPOSITION,

0,(LParaM)MAKELONG(pt.x + 10,pt.y - 20));

}

return FALSE;

case WM_DESTROY:

PostQuitMessage(0);

return 0;

}

return DefWindowProc(hwnd,message,wParam,lParam);

}

HWND CreateTrackingToolTip(int toolID,char *pText)

{

// Create a ToolTip.

HWND hwndTT = CreateWindowEx(WS_EX_TOPMOST,

TOOLTIPS_CLASS,

WS_POPUP | TTS_nopREFIX | TTS_ALWAYSTIP,CW_USEDEFAULT,

hDlg,g_hInst,NULL);

if (!hwndTT)

{

return NULL;

}

// Set up tool information.

// In this case,the "tool" is the entire parent window.

g_toolItem.cbSize = sizeof(TOOLINFO);

//g_toolItem.cbSize = TTTOOLINFOA_V2_SIZE;

g_toolItem.uFlags = TTF_IdisHWND | TTF_TRACK | TTF_ABSOLUTE;

g_toolItem.hwnd = hDlg;

g_toolItem.hinst = g_hInst;

g_toolItem.lpszText = pText;

g_toolItem.uId = (UINT_PTR)hDlg;

GetClientRect (hDlg,&g_toolItem.rect);

// Associate the ToolTip with the tool window.

SendMessage(hwndTT,TTM_ADDTOOL,(LParaM) (LPTOOLINFO)&g_toolItem);

return hwndTT;

}