收到 'bad_weak_ptr' 错误
Getting 'bad_weak_ptr' error
我正在尝试将一个共享指针从 QTGUI
class 传递到 Client
class,并不断收到 bad weak ptr
错误。我已经读到我不能在构造函数中直接分配 shared_from_this()
,因为此时指针还没有准备好。
因此,我创建了一个 getptr
函数,该函数 returns 对象的指针,以便稍后在进一步调用中将其分配给客户端。但是它似乎也不起作用。
我在这里错过了什么?非常感谢您。
qtgui.hpp
#ifndef QTGUI_H
#define QTGUI_H
#include <QMainWindow>
#include <QFileSystemWatcher>
#include <boost/enable_shared_from_this.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/signals2.hpp>
#include <boost/bind.hpp>
class Client;
namespace Ui {
class QTGUI;
}
class QTGUI : public QMainWindow, public boost::enable_shared_from_this<QTGUI>
{
Q_OBJECT
public:
explicit QTGUI(QWidget *parent = 0);
~QTGUI();
void start();
boost::shared_ptr<QTGUI> getptr();
/* Signals */
typedef boost::signals2::signal
<void (const char* ipaddress, const char* port)> start_connect;
typedef start_connect::slot_type start_connect_st;
boost::signals2::connection start_connect_ui(const start_connect_st& slot);
private slots:
private:
Ui::QTGUI *ui;
boost::shared_ptr<Client> client_;
start_connect sc_signal;
};
#endif // QTGUI_H
qtgui.cpp
#include "qtgui.h"
#include "ui_qtgui.h"
#include <iostream>
#include <QHostAddress>
#include <QRegExp>
#include <QIntValidator>
#include <QFileDialog>
#include <unistd.h>
#include <pwd.h>
#include <sys/types.h>
#include "../client/client.hpp"
#include <boost/bind.hpp>
#include <boost/thread.hpp>
QTGUI::QTGUI(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::QTGUI),
connected_(false),
client_(new Client)
{
start();
}
boost::shared_ptr< QTGUI > QTGUI::getptr()
{
return shared_from_this();
}
void QTGUI::start()
{
client_->addui(getptr());
client_->get_con_status(boost::bind(&QTGUI::connection_status, this,
_1));
}
boost::signals2::connection QTGUI::start_connect_ui(const start_connect_st&
slot)
{
return sc_signal.connect(slot);
}
client.hpp
#ifndef CLIENT_HPP
#define CLIENT_HPP
#include <boost/asio.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/enable_shared_from_this.hpp>
#include <boost/scoped_ptr.hpp>
#include <boost/thread.hpp>
#include <boost/signals2.hpp>
#include "../common/message.hpp"
class QTGUI;
class Client : public boost::enable_shared_from_this<Client>
{
public:
Client(/*boost::shared_ptr<QTGUI> ui*/);
void addui(boost::shared_ptr<QTGUI> ptr);
/* Signals */
typedef boost::signals2::signal<void (bool status)> connect_status;
typedef connect_status::slot_type connect_status_st;
boost::signals2::connection get_con_status(const connect_status_st& slot);
private:
boost::shared_ptr<QTGUI> ui_;
boost::shared_ptr<boost::thread> thread_;
boost::shared_ptr<boost::asio::io_service> io_service_;
boost::shared_ptr<boost::asio::io_service::work> work_;
boost::shared_ptr<boost::asio::ip::tcp::socket> socket_;
connect_status cs_sig;
};
#endif// client.hpp
client.cpp
#include <boost/bind.hpp>
#include <boost/bind/protect.hpp>
#include <boost/function.hpp>
#include <cstdio> /* sprintf */
#include "client.hpp"
#include "../common/commands.hpp"
#include "../common/kinotify.hpp"
#include "../gui/qtgui.h"
#include <functional>
#include <unistd.h>
Client::Client(/*boost::shared_ptr<QTGUI> ui*/):
//ui_(ui),
io_service_(new boost::asio::io_service),
work_(new boost::asio::io_service::work(*io_service_)),
connected_(false)
{
start();
}
void Client::addui(boost::shared_ptr< QTGUI > ptr)
{
ui_ = ptr;
std::cout << "Connecting..." << std::endl;
ui_->start_connect_ui(boost::bind(&Client::post_connect,
shared_from_this(), _1, _2));
}
void Client::start()
{
if(thread_)
return;
std::cout << "Creating new thread bruh" << std::endl;
thread_.reset(new boost::thread(
boost::bind(&boost::asio::io_service::run, io_service_)
));
std::cout << "start Thread ID [" << boost::this_thread::get_id() <<
"]" << std::endl;
}
void Client::stop()
{
if(!thread_)
return;
std::cout << "Ending" << std::endl;
socket_->shutdown(boost::asio::ip::tcp::socket::shutdown_both);
socket_->close();
io_service_->stop();
thread_->join();
io_service_->reset();
thread_.reset();
}
boost::signals2::connection Client::get_con_status(const connect_status_st&
slot)
{
return cs_sig.connect(slot);
}
编辑:添加main.cpp
#include "qtgui.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QTGUI w;
w.start();
w.show();
return a.exec();
}
I have read that I can't assign an shared_from_this() directly in a constructor, because the pointer is not ready at that point.
是的,在对象完全构建之前不能使用 shared_from_this()
。只有在那个时候,基础 weak_ptr
才被分配。限制不仅仅是来自构造函数的 直接 - 你仍然在 QTGUI
完全构造之前调用 shared_from_this
。您正在使用一个函数从另一个函数检索它这一事实并不重要。
创建 class 后,只需在外部调用 start()
。那会起作用的。
旁注:getptr()
没用。直接用shared_from_this()
就可以了。
我正在尝试将一个共享指针从 QTGUI
class 传递到 Client
class,并不断收到 bad weak ptr
错误。我已经读到我不能在构造函数中直接分配 shared_from_this()
,因为此时指针还没有准备好。
因此,我创建了一个 getptr
函数,该函数 returns 对象的指针,以便稍后在进一步调用中将其分配给客户端。但是它似乎也不起作用。
我在这里错过了什么?非常感谢您。
qtgui.hpp
#ifndef QTGUI_H
#define QTGUI_H
#include <QMainWindow>
#include <QFileSystemWatcher>
#include <boost/enable_shared_from_this.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/signals2.hpp>
#include <boost/bind.hpp>
class Client;
namespace Ui {
class QTGUI;
}
class QTGUI : public QMainWindow, public boost::enable_shared_from_this<QTGUI>
{
Q_OBJECT
public:
explicit QTGUI(QWidget *parent = 0);
~QTGUI();
void start();
boost::shared_ptr<QTGUI> getptr();
/* Signals */
typedef boost::signals2::signal
<void (const char* ipaddress, const char* port)> start_connect;
typedef start_connect::slot_type start_connect_st;
boost::signals2::connection start_connect_ui(const start_connect_st& slot);
private slots:
private:
Ui::QTGUI *ui;
boost::shared_ptr<Client> client_;
start_connect sc_signal;
};
#endif // QTGUI_H
qtgui.cpp
#include "qtgui.h"
#include "ui_qtgui.h"
#include <iostream>
#include <QHostAddress>
#include <QRegExp>
#include <QIntValidator>
#include <QFileDialog>
#include <unistd.h>
#include <pwd.h>
#include <sys/types.h>
#include "../client/client.hpp"
#include <boost/bind.hpp>
#include <boost/thread.hpp>
QTGUI::QTGUI(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::QTGUI),
connected_(false),
client_(new Client)
{
start();
}
boost::shared_ptr< QTGUI > QTGUI::getptr()
{
return shared_from_this();
}
void QTGUI::start()
{
client_->addui(getptr());
client_->get_con_status(boost::bind(&QTGUI::connection_status, this,
_1));
}
boost::signals2::connection QTGUI::start_connect_ui(const start_connect_st&
slot)
{
return sc_signal.connect(slot);
}
client.hpp
#ifndef CLIENT_HPP
#define CLIENT_HPP
#include <boost/asio.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/enable_shared_from_this.hpp>
#include <boost/scoped_ptr.hpp>
#include <boost/thread.hpp>
#include <boost/signals2.hpp>
#include "../common/message.hpp"
class QTGUI;
class Client : public boost::enable_shared_from_this<Client>
{
public:
Client(/*boost::shared_ptr<QTGUI> ui*/);
void addui(boost::shared_ptr<QTGUI> ptr);
/* Signals */
typedef boost::signals2::signal<void (bool status)> connect_status;
typedef connect_status::slot_type connect_status_st;
boost::signals2::connection get_con_status(const connect_status_st& slot);
private:
boost::shared_ptr<QTGUI> ui_;
boost::shared_ptr<boost::thread> thread_;
boost::shared_ptr<boost::asio::io_service> io_service_;
boost::shared_ptr<boost::asio::io_service::work> work_;
boost::shared_ptr<boost::asio::ip::tcp::socket> socket_;
connect_status cs_sig;
};
#endif// client.hpp
client.cpp
#include <boost/bind.hpp>
#include <boost/bind/protect.hpp>
#include <boost/function.hpp>
#include <cstdio> /* sprintf */
#include "client.hpp"
#include "../common/commands.hpp"
#include "../common/kinotify.hpp"
#include "../gui/qtgui.h"
#include <functional>
#include <unistd.h>
Client::Client(/*boost::shared_ptr<QTGUI> ui*/):
//ui_(ui),
io_service_(new boost::asio::io_service),
work_(new boost::asio::io_service::work(*io_service_)),
connected_(false)
{
start();
}
void Client::addui(boost::shared_ptr< QTGUI > ptr)
{
ui_ = ptr;
std::cout << "Connecting..." << std::endl;
ui_->start_connect_ui(boost::bind(&Client::post_connect,
shared_from_this(), _1, _2));
}
void Client::start()
{
if(thread_)
return;
std::cout << "Creating new thread bruh" << std::endl;
thread_.reset(new boost::thread(
boost::bind(&boost::asio::io_service::run, io_service_)
));
std::cout << "start Thread ID [" << boost::this_thread::get_id() <<
"]" << std::endl;
}
void Client::stop()
{
if(!thread_)
return;
std::cout << "Ending" << std::endl;
socket_->shutdown(boost::asio::ip::tcp::socket::shutdown_both);
socket_->close();
io_service_->stop();
thread_->join();
io_service_->reset();
thread_.reset();
}
boost::signals2::connection Client::get_con_status(const connect_status_st&
slot)
{
return cs_sig.connect(slot);
}
编辑:添加main.cpp
#include "qtgui.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QTGUI w;
w.start();
w.show();
return a.exec();
}
I have read that I can't assign an shared_from_this() directly in a constructor, because the pointer is not ready at that point.
是的,在对象完全构建之前不能使用 shared_from_this()
。只有在那个时候,基础 weak_ptr
才被分配。限制不仅仅是来自构造函数的 直接 - 你仍然在 QTGUI
完全构造之前调用 shared_from_this
。您正在使用一个函数从另一个函数检索它这一事实并不重要。
创建 class 后,只需在外部调用 start()
。那会起作用的。
旁注:getptr()
没用。直接用shared_from_this()
就可以了。