WINAPI MessageBox在消息队列中调用时，无法正常显示

Question

蹦跶的钟 20

不会立即显示，但是可以使用Enter关闭消息框。只有按Alt时，消息框才会显示出来。调用代码为

case WM_LBUTTONDOWN: { MessageBox(NULL, L"123", L"错误", MB_OK); } return 0；

1 个答案

Answer 1

Omkara Varshitha Kunapalli (INFOSYS LIMITED) 1,985 Microsoft 外部员工

Hello Thanks for reaching out !

Use window handle as owner: Call MessageBoxW(hWnd, L"123", L"错误", MB_OK); instead of NULL.

Force foreground: Add MB_SETFOREGROUND (and MB_TOPMOST if your window is topmost).
Defer from input handler: Post a custom message in WM_LBUTTONDOWN instead of showing directly.
Show in custom handler: Handle WM_SHOW_MSGBOX and call MessageBoxW(hWnd, L"123", L"错误", MB_OK | MB_SETFOREGROUND);.
Return DefWindowProc: For all unhandled messages, return DefWindowProc
Example:
#define WM_SHOW_MSGBOX (WM_USER + 1)
case WM_LBUTTONDOWN: PostMessage(hWnd, WM_SHOW_MSGBOX, 0, 0); return 0; case WM_SHOW_MSGBOX: MessageBoxW(hWnd, L"123", L"错误", MB_OK | MB_SETFOREGROUND); return 0;