(C++) Wt with Qt under Qt Creator under Lubuntu

January 25, 2018 · View on GitHub

(C++) Wt with Qt under Qt Creator under Lubuntu

Wt with Qt under Qt Creator under Lubuntu does not appear to work: it results in a runtime error.

Download the Qt Creator project 'CppWtWithQtQtCreatorLubuntu' (zip)

Technical facts

Application type(s)

Web application

Operating system(s) or programming environment(s)

Lubuntu 11.04 (natty)

Qt Creator 2.0.1

Console application

C++98

G++ 4.5.2

Libraries used:

Boost: version 1.42
Qt: version 4.7.2 (32 bit)
STL: GNU ISO C++ Library, version 4.5.2
Wt: version 3.1.9

Qt project file: CppWtWithQt.pro

#------------------------------------------------- # # Project created by QtCreator 2010-12-29T21:57:10 # #------------------------------------------------- QT += core QT -= gui INCLUDEPATH += lib LIBS += -lwt -lwthttp QMAKE_CXXFLAGS += -DNDEBUG TARGET = CppWtWithQt CONFIG += console CONFIG -= app_bundle TEMPLATE = app SOURCES += hello.cpp \ QtObject.cpp \ lib/WQApplication.cpp \ lib/DispatchThread.cpp HEADERS += \ QtObject.h \ HelloApplication.h \ lib/WQApplication.h \ lib/DispatchThread.h

HelloApplication.h

// This may look like C code, but it's really --$ C++ -- /* * Copyright 2008 Emweb bvba, Heverlee, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #ifndef HELLO_APPLICATION_H_ #define HELLO_APPLICATION_H_ #include "WQApplication.h" class QtObject; class QString; using namespace Wt; namespace Wt { class WLineEdit; class WText; } /! \class HelloApplication * \brief The 'hello' application modified to use QtCore * * A sample application that uses objects from the QtCore library. / class HelloApplication : public WQApplication { public: HelloApplication(const WEnvironment& env); void doGreet(const QString&); virtual void create(); virtual void destroy(); private: WLineEdit nameEdit_; WText greeting_; QtObject qtSender_, *qtReceiver_; void propagateGreet(); }; #endif // HELLO_APPLICATION_H_

QtObject.cpp

/* * Copyright 2008 Emweb bvba, Heverlee, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #include "HelloApplication.h" #include "QtObject.h" QtObject::QtObject(HelloApplication wt, QObject *parent) : QObject(parent), wt_(wt) { } void QtObject::passGreet(const QString& name) { emit greet(name); } void QtObject::doGreet(const QString& name) { wt_->doGreet(name); }

QtObject.h

// This may look like C code, but it's really --$ C++ -- /* * Copyright 2008 Emweb bvba, Heverlee, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #ifndef QTOBJECT_H_ #define QTOBJECT_H_ #ifdef SLOT # undef SLOT # undef signals # undef slots #endif #include <vector> #include <QThread> class HelloApplication; /! \class QtObject * \brief A simple Qt object with sample signal and slot. * * This simple object class demonstrates that the Qt signal/slot * mechanism may be used alonglisde Wt's signal/slot mechanism. / class QtObject : public QObject { Q_OBJECT; public: QtObject(HelloApplication wt_, QObject parent = 0); void passGreet(const QString&); signals: void greet(const QString&); public slots: void doGreet(const QString&); private: HelloApplication wt_; }; #endif // QTOBJECT_H_

hello.cpp

/* * Copyright 2008 Emweb bvba, Heverlee, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #include <iostream> #include <vector> #include <boost/program_options.hpp> #include <Wt/WBreak> #include <Wt/WContainerWidget> #include <Wt/WLineEdit> #include <Wt/WPushButton> #include <Wt/WText> #include "HelloApplication.h" #include "QtObject.h" using namespace Wt; HelloApplication::HelloApplication(const WEnvironment& env) : WQApplication(env) { / * Note: do not create any Qt objects from here. Initialize your * application from within the virtual create() method. / } void HelloApplication::create() { setTitle("CppWtWithQt"); root()->addWidget(new WText("Your name, please ? ")); nameEdit_ = new WLineEdit(root()); nameEdit_->setFocus(); WPushButton b = new WPushButton("Greet me.", root()); b->setMargin(5, Left); root()->addWidget(new WBreak()); greeting_ = new WText(root()); b->clicked().connect(this, &HelloApplication::propagateGreet); nameEdit_->enterPressed().connect(this, &HelloApplication::propagateGreet); qtSender_ = new QtObject(this); qtReceiver_ = new QtObject(this); QObject::connect(qtSender_, SIGNAL(greet(const QString&)), qtReceiver_, SLOT(doGreet(const QString&))); } void HelloApplication::destroy() { /* * Note: Delete any Qt object from here. / delete qtSender_; delete qtReceiver_; } void HelloApplication::propagateGreet() { qtSender_->passGreet(toQString(nameEdit_->text())); } void HelloApplication::doGreet(const QString& qname) { greeting_->setText("Hello there, " + toWString(qname)); } WApplication createApplication(const WEnvironment& env) { return new HelloApplication(env); } int main(int argc, char **argv) { // Declare the supported options. boost::program_options::options_description d( "Allowed options for TestLed"); std::string docroot; std::string http_address; std::string http_port; d.add_options() ("help", "produce this help message") ("docroot", boost::program_options::value<std::string>(&docroot)->default_value("."), "the docroot") ("http-address", boost::program_options::value<std::string>(&http_address)->default_value("0.0.0.0"), "the server's http address") ("http-port", boost::program_options::value<std::string>(&http_port)->default_value("8080"), "the server's http port") ; boost::program_options::variables_map m; boost::program_options::store( boost::program_options::parse_command_line( argc, argv, d), m); boost::program_options::notify(m); if (m.count("help")) { //Display the options_description std::cout << d << "\n"; return 0; } //Create the arguments in std::string format std::vector<std::string> v(7); v[0] = argv[0]; v[1] = "--docroot"; v[2] = docroot; v[3] = "--http-address"; v[4] = http_address; v[5] = "--http-port"; v[6] = http_port; //Convert the arguments to char* format std::vector<char*> w(7); for (int i=0; i!=7; ++i) w[i] = &v[i][0]; //Give Wt the modified parameters return WRun(w.size(), &w[0], &createApplication); //OLD: //return WRun(argc, argv, &createApplication); }

lib/DispatchThread.cpp

/* * Copyright 2008 Emweb bvba, Kessel-Lo, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #include "WQApplication.h" #include "DispatchThread.h" namespace Wt { DispatchObject::DispatchObject(DispatchThread thread) : thread_(thread) { connect(this, SIGNAL(doEvent()), this, SLOT(onEvent())); } void DispatchObject::propagateEvent() { emit doEvent(); } void DispatchObject::onEvent() { thread_->doEvent(); } DispatchThread::DispatchThread(WQApplication app, bool withEventLoop) : QThread(), app_(app), qtEventLoop_(withEventLoop), dispatchObject_(0), event_(0), done_(false), newEvent_(false) { } void DispatchThread::run() { app_->attachThread(); app_->create(); if (qtEventLoop_) dispatchObject_ = new DispatchObject(this); signalDone(); if (qtEventLoop_) exec(); else myExec(); delete dispatchObject_; signalDone(); } void DispatchThread::myExec() { boost::mutex::scoped_lock lock(newEventMutex_); for (;;) { if (!newEvent_) newEventCondition_.wait(lock); if (doEvent()) return; newEvent_ = false; } } void DispatchThread::myPropagateEvent() { boost::mutex::scoped_lock lock(newEventMutex_); newEvent_ = true; newEventCondition_.notify_one(); } void DispatchThread::signalDone() { boost::mutex::scoped_lock lock(doneMutex_); done_ = true; doneCondition_.notify_one(); } void DispatchThread::waitDone() { boost::mutex::scoped_lock lock(doneMutex_); if (done_) return; else doneCondition_.wait(lock); } void DispatchThread::notify(const WEvent& event) { event_ = &event; done_ = false; if (dispatchObject_) dispatchObject_->propagateEvent(); else myPropagateEvent(); waitDone(); } void DispatchThread::destroy() { event_ = 0; done_ = false; if (dispatchObject_) dispatchObject_->propagateEvent(); else myPropagateEvent(); waitDone(); wait(); } bool DispatchThread::doEvent() { if (event_) { app_->realNotify(event_); signalDone(); return false; } else { app_->destroy(); if (qtEventLoop_) QThread::exit(); return true; } } }

lib/DispatchThread.h

// This may look like C code, but it's really --$ C++ -- /* * Copyright 2008 Emweb bvba, Kessel-Lo, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #ifndef DISPATCH_THREAD_H_ #define DISPATCH_THREAD_H_ #include <QThread> #include <boost/thread.hpp> #include <boost/thread/condition.hpp> namespace Wt { class WQApplication; class WEvent; class DispatchThread; / * Help object used to dispatch an event into a Qt event loop. / class DispatchObject : public QObject { Q_OBJECT; public: DispatchObject(DispatchThread thread); void propagateEvent(); signals: void doEvent(); private slots: void onEvent(); private: DispatchThread thread_; }; / * Thread in which all interaction with Qt objects is done. * * If constructed <i>withEventLoop</i>, then QThread::exec() is * called, starting a new Qt event loop, and signal/slot events can be * delivered within the event loop handling. Otherwise, plain thread * synchronization is implemented. / class DispatchThread : public QThread { public: DispatchThread(WQApplication app, bool withEventLoop); virtual void run(); void notify(const WEvent& event); void destroy(); void waitDone(); private: WQApplication app_; bool qtEventLoop_; DispatchObject dispatchObject_; const WEvent *event_; boost::mutex doneMutex_; bool done_; boost::condition doneCondition_; boost::mutex newEventMutex_; bool newEvent_; boost::condition newEventCondition_; bool doEvent(); void signalDone(); void myExec(); void myPropagateEvent(); friend class DispatchObject; }; } #endif // DISPATCH_THREAD_H_

lib/WQApplication.cpp

/* * Copyright 2008 Emweb bvba, Kessel-Lo, Belgium. * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. / #include <iostream> #include <boost/thread/condition.hpp> #include "WQApplication.h" #include "DispatchThread.h" namespace { } namespace Wt { WQApplication::WQApplication(const WEnvironment& env, bool withEventLoop) : WApplication(env), withEventLoop_(withEventLoop), thread_(0) { } void WQApplication::initialize() { if (thread_) return; thread_ = new DispatchThread(this, withEventLoop_); thread_->start(); thread_->waitDone(); } void WQApplication::finalize() { if (!thread_) return; thread_->destroy(); delete thread_; thread_ = 0; } void WQApplication::notify(const WEvent& e) { thread_->notify(e); } void WQApplication::realNotify(const WEvent& e) { WApplication::notify(e); } WString toWString(const QString& s) { return WString::fromUTF8((const char )s.toUtf8()); } QString toQString(const WString& s) { return QString::fromUtf8(s.toUTF8().c_str()); } }

lib/WQApplication.h