Qt signals and slots for multiple objects

问题

I'm having little problem here. I'm having troubles with signals & slots. I'll try to explain with pseudocode. So, here it goes.

I have main thread (mainwindow.cpp) where I'm creating new objects when new client connects.

mainwindow.h:

signals:
   void changeText();
...

mainwindow.cpp:

connect(tcpserver, SIGNAL(changeText()), this, SIGNAL(changeText()));

...

MyClass *m = new MyClass(this);
connect(this, SIGNAL(changeText()), m, SLOT(changeText()));

I have also tcpserver class, which creates new QThread when client connects and connects both signals.

tcpserver.h:

signals:
    void changeText();
protected:
    void incomingConnection(int handle);

tcpserver.cpp:

void incomingConnection(int handle)
{
    QTcpSocket *s = new QTcpSocket(this);
    s->setSocketDescriptor(handle);
    mythread *thread = new mythread(s, this);
    connect(thread, SIGNAL(changeText()), this, SIGNAL(changeText()));
}

The problem is following: I have 3 objects, main thread, tcpserver class which inherits from QTcpServer, and the mythread class which inherits from QThread class.

When I'm creating new "mythread"-s from "tcpserver" and connecting signals, all signals from new threads are connected to "tcpserver"-s signals, so, e.g if 10 clients do something, all signals are sent to "tcpserver" which makes problem for me. I want to understand which signal should I connect to MyClass via QTread -> TcpServer -> MainWindow.

Sorry for my English, if you don't understand what I mean, I'll try to explain better.

Thank you.

回答1:

Some suggestions:

in your "incomingConnection(int)", i doubt any memory leak for the objects created in heap (tcpsocket, and mythread), use QList (or other container) in your tcpserver to hold the sockets created in your "incomingConnection(int)"
prefix the name of SLOT(changeText) with your classes to clarify which objects is your intented sender/receiver
I dont think you cant connect two signal like

connect(thread, SIGNAL(changeText()), this, SIGNAL(changeText()));

来源：https://stackoverflow.com/questions/15316032/qt-signals-and-slots-for-multiple-objects

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signals-slots