解决WaitForSingleObject阻塞UI线程的问题

来源：清泛编译 2016-11-09 11:23:36 人气：我有话说( 0 人参与)

WaitForSingleObjec 等待线程结束时会阻塞UI线程，导致界面不响应鼠标操作。解决原理：等待过程中对消息队列中消息进行转发处理。代码如下...

WaitForSingleObjec 等待线程结束时会阻塞UI线程，导致界面不响应鼠标操作。
解决原理：等待过程中对消息队列中消息进行转发处理。

代码如下：

// 等待线程运行结束，WaitForSingleObject会阻塞UI线程
	MSG msg;
	DWORD dwRet;
	while (TRUE)  
	{
		//wait for m_hThread to be over，and wait for
		//QS_ALLINPUT（Any message is in the queue）
		dwRet = MsgWaitForMultipleObjects(1, &hThread, FALSE, INFINITE, QS_ALLINPUT);
		switch(dwRet)
		{
		case WAIT_OBJECT_0:
			break; //break the loop
		case WAIT_OBJECT_0 + 1:
			//get the message from Queue
			//and dispatch it to specific window
			PeekMessage(&msg, NULL, 0, 0, PM_REMOVE);
			DispatchMessage(&msg);
			continue;
		default:
			break; // unexpected failure
		}
		break;
	}

	//显示主界面
	...

使用 MsgWaitForMultipleObjects代替 WaitForSingleObject，这个函数即可以等待信号（thread,event,mutex等等），也可以等待指定类型的消息（MSG），函数声明如下：

DWORD WINAPI MsgWaitForMultipleObjects(
        __in                         DWORD nCount, //number of objects to be wait
        __in                         const HANDLE* pHandles, //An array of object handles.
        __in                         BOOL bWaitAll, //If this parameter is TRUE, the function returns when the states
                                                    //of all objects in the pHandles array have been set to signaled
                                                    //and an message has been received.
        __in                         DWORD dwMilliseconds, //time-out interva
        __in                         DWORD dwWakeMask //the type of message to be wait
      );