上一篇文章,存在失去焦点问题,分析可能原因是直接将子进程的窗口句柄封装到QWindow对象中之后,窗口的键盘事件可能就qt自己处理,但是目前没有搞清楚怎么处理的.
下面这种方式也类似第一种方式,不同点在于处理窗口句柄的方式.
通过自定义一个QWindow的一个子类,在子类中通过window平台api将子进程窗口的句柄与子类对象形成父子关系.然后在将子类封装为QWidget供qt主进程的其他控件使用.这种方式的优点是不存在失去焦点问题.但是要处理win7下的其他问题.
笔者在win7下出现的问题:
1.当子进程非全屏模式时,当通过QProcess启动这个子进程窗口时,出现卡住的问题,并且不会显示该窗口. 只有将子进程的设置为 showFullScreen()后,就能正常启动了.分析可能原因时,window平台api设置窗口为无边框及工具窗口对于qt窗口无效,只能通过子进程内部设置好.
2.当主进程窗口是showFullScreen()状态时,子进程存在QDailog窗口,或者一些其他控件的操作时,会出现window桌面任务栏弹出的现象.win10下正常. 笔者通过判断当前操作系统版本,然后通过将任务栏的自动隐藏功能开启后,可通软件层面技术性解决该问题.将任务栏自动隐藏功能开启后,及时存在弹出现象,也因为隐藏后,不会显示. 当软件退出时,再取消该功能.
代码1: 自定义一个QWindow子类
#include <windows.h>
#include <QWindow>//创建子进程用的QWindow子类
class ChildWindowWrapper : public QWindow {
public:/// <summary>/// 构造一个Qwindow子类对象/// </summary>/// <param name="hwnd">子进程创建句柄</param>/// <param name="parent">Qwindow对象的父对象</param>ChildWindowWrapper(HWND hwnd, QWindow* parent = nullptr): QWindow(parent), m_hwnd(hwnd) {embedChildWindow();}~ChildWindowWrapper(){if (m_hwnd) {SetParent(m_hwnd, NULL);}}void embedChildWindow() {// 修改子窗口样式,去掉标题栏和边框 win7下,qt窗口好像无效了,所以通过子进程内部将窗口设置为全屏LONG style = GetWindowLong(m_hwnd, GWL_STYLE);style &= ~(WS_CAPTION | WS_THICKFRAME);style|= WS_EX_TOOLWINDOW;SetWindowLong(m_hwnd, GWL_STYLE, style);//关键点,通过window api 将当前QWindow对象设置为子进程窗口的父对象窗口SetParent(m_hwnd, (HWND)winId());//这个也很重要,将子进程窗口设置为无边框及标题栏的窗口 ,在win7下才不会弹出底下的状态栏.,win10没有这个也正常//SWP_FRAMECHANGED刷新一次上述更改的状态.SWP_NOZORDER保存窗口为层级不变SetWindowPos(m_hwnd, nullptr, 0, 0, width(), height(), SWP_NOACTIVATE | SWP_FRAMECHANGED);// 显示子进程窗口//ShowWindow(m_hwnd, SW_SHOW);//SetForegroundWindow(m_hwnd);//SetFocus(m_hwnd);}protected:bool event(QEvent* event) override {if (event->type() == QEvent::Resize) {if (m_hwnd) {//SetWindowPos(m_hwnd, nullptr, 0, 0, width(), height(), SWP_NOZORDER | SWP_NOACTIVATE);SetWindowPos(m_hwnd, nullptr, 0, 0, width(), height(), SWP_NOACTIVATE);}}return QWindow::event(event);}private://子进程窗口的句柄HWND m_hwnd;
};
//头文件中定义子类对象指针
ChildWindowWrapper* m_ChildVMWin{ nullptr };
具体代码实现
//window 底层操作,隐藏window桌面的任务栏功能,在win7下/// <summary>
/// 获取window版本
/// </summary>
/// <returns>0为win7,1为win10,其他为-1</returns>
int CncOpWindows::GetWindowsVerson()
{int iType{ 0 };QString osName = QSysInfo::productType();//qDebug() << "Operating System:" << osName;if (osName == "windows"){ if (QSysInfo::windowsVersion() == QSysInfo::WV_WINDOWS7){//qDebug() << "Windows 7";iType = 0;}else if (QSysInfo::windowsVersion() == QSysInfo::WV_WINDOWS10) {//qDebug() << "Windows 10";iType = 1;}else{//其他windows系统iType = 2;}}else {//qDebug() << "Other OS";iType = -1;}return iType;
}void CncOpWindows::FindWindowsTaskBarHandle()
{
//windows任务栏句柄hwndWindowsTaskBar = FindWindow("Shell_TrayWnd", NULL);
}void CncOpWindows::HideWindowsTaskBar()
{if(hwndWindowsTaskBar)SetAutoHideWindowsTaskbar(true);}
void CncOpWindows::ShowWindowsTaskBar()
{if (hwndWindowsTaskBar)SetAutoHideWindowsTaskbar(false);
}void CncOpWindows::SetAutoHideWindowsTaskbar(bool enable)
{
//开启/关闭任务栏自动隐藏功能APPBARDATA appBarData = { 0 };appBarData.cbSize = sizeof(APPBARDATA);appBarData.hWnd = hwndWindowsTaskBar;if (enable) {appBarData.lParam = ABS_AUTOHIDE ;}else {appBarData.lParam = 0;}SHAppBarMessage(ABM_SETSTATE, &appBarData);
}void CncOpWindows::CreateShareMem()
{
//创建共享内存,与子进程通信用, 通过变量控制子进程的退出与显示m_pShareMemObj = new qcShareMemory(nullptr);m_pThreadShareMem = new QThread(this);m_pThreadShareMem->setObjectName(tr("ShareMenThread"));m_pShareMemObj->moveToThread(m_pThreadShareMem);connect(m_pThreadShareMem, &QThread::started, m_pShareMemObj, &qcShareMemory::slotInit);connect(m_pThreadShareMem, &QThread::finished, m_pShareMemObj, &qcShareMemory::slotFinish);connect(this, &CncOpWindows::signalReadWriteShareMem, m_pShareMemObj, &qcShareMemory::slotReadWriteShareMem);connect(m_pShareMemObj, &qcShareMemory::signalShowLastWnd, this, &CncOpWindows::slotShowLastWnd);m_pThreadShareMem->start();m_pShareMemObj->m_bStart = true;emit signalReadWriteShareMem();
}bool CncOpWindows::LoadVisionMeasureApp()
{QString cmd= QCoreApplication::applicationDirPath();int iCamAppType = 0;switch (iCamAppType){case 0:cmd += "/ImageGrab.exe";//子程序执行文件地址break;case 5:cmd += "/MeasureVM.exe";//子程序执行文件地址break;}QStringList argList;argList << QString::number(ui->stackedWidget_sub->winId());//把父窗口的id给子进程传递过去m_pProcessVM = new QProcess(this);//使用进程运行子进程窗口connect(m_pProcessVM, &QProcess::readyReadStandardError, this, &CncOpWindows::slotCreateWaitingVM);//等待子进程窗口把自身的winId传递过来connect(m_pProcessVM, qOverload<int, QProcess::ExitStatus>(&QProcess::finished), this, qOverload<int , QProcess::ExitStatus>(&CncOpWindows::slotFinishedProcessVM));//connect(m_pProcessVM, &QProcess::readyRead, this, &CncOpWindows::slotReadProcessVM);m_pProcessVM->start(cmd, argList);return m_pProcessVM->waitForStarted(2000);
}void CncOpWindows::slotCreateWaitingVM()
{quint64 winId = m_pProcessVM->readAllStandardError().toLongLong();m_ChildVMWin = new ChildWindowWrapper((HWND)winId, ui->stackedWidget_sub->windowHandle());//m_ChildVMWin = QWindow::fromWinId(winId);if (m_ChildVMWin){//m_ChildVMWin->setParent(ui->stackedWidget_sub->windowHandle());m_WidgetVMProcess = QWidget::createWindowContainer(m_ChildVMWin);//获取一个子进程窗口的widget// 调整窗口大小以适应控件大小ui->stackedWidget_sub->addWidget(m_WidgetVMProcess);//这里是可以使用布局器管理子进程窗口的,不管理的话就在坐标0,0处}}void CncOpWindows::slotFinishedProcessVM(int exitCode, QProcess::ExitStatus exitStatus)
{qInfo() << "ImageGrab.exe quit"<<"[exitCode="<< exitCode << "ExitStatus=" << exitStatus << "]";//if (exitStatus== QProcess::NormalExit)//{// //正常退出//}//else//{// //非正常退出//}}void CncOpWindows::CloseVisionMeasureApp()
{//关闭当前视觉测量进程if (m_pProcessVM){////关键点,必须将嵌入的QWindow设置为没有父对象,在调用退出指令就正常了/* if (m_ChildVMWin){m_ChildVMWin->setParent(nullptr);}*///正常退出程序terminate 发送一个close消息到顶层窗口.//m_pProcessVM->terminate();//结束app信号 共享内存与子进程通信if (PointGlobalParams()->m_pDataApp){PointGlobalParams()->m_pDataApp->bC2V[1] = true;}//等待结束不能省,bool bFinish=m_pProcessVM->waitForFinished(5000);if (!bFinish){//非正常退出qInfo() << "ImageGrab.exe crash quit";}}}
子进程实现
//mian函数中的实现,只需要传递子进程窗口的winid,也即window下的窗口句柄if (argc >1){//关键代码,触发错误之后,主进程能够响应fprintf(stderr, "%lld", (quint64)w.winId());//写入标准错误输出,stderr能立即输出,stdout则不行w.hide();}else{w.show();}
//定义一个定时器,时刻监控共享内存的状态,来执行下面这两个函数
//显示当前app
void ImageGrab::slotShowApp()
{//将当前窗口处于激活状态m_pGlobalPa->m_pDataApp->bV2C[0] = true;if (this->isHidden()){this->show();this->activateWindow();}
}void ImageGrab::slotCloseApp()
{//将当前app关闭this->close();
}