Why the QT QNetworkAccessManager example dont works in my Program ? - c++

Question

i would write a programm that becomes data from a Url. When i open this Url with firefox, i became a .json data. The same i would make with my qt project: Open a url, that returns the same .json data. I must use the QNetworkAccessManager, right ?
But when i use the example from the qt project site, it make a syntax error. I have make all includes.
This is the code from the example , i use the same in my project.:
QNetworkRequest request;
QNetworkAccessManager *manager = new QNetworkAccessManager(this);
connect(manager, SIGNAL(finished(QNetworkReply*)),
this, SLOT(replyFinished(QNetworkReply*)));
QNetworkReply *reply = manager->get(request);
manager->get(QNetworkRequest(QUrl("http://qt.nokia.com")));
request.setUrl(QUrl("http://qt.nokia.com"));
I know that this dont returns me my .json data, but at first i will can opened a url.
Why my program make a syntax error. When i delete this, my program works. ( Without parsing, but it views and the buttoncklicks works.
Thank you

Answer 1

It seams you got error message something like this "invalid use of 'this' in non-member function" right?
When you use *this pointer it should point to some object.
You have to do something like here:
class Request : public QObject {
Q_OBJECT
public:
Request(QObject *parent=0);
~Request();
public slots:
void replyFinished(QNetworkReply *))
private:
QNetworkAccessManager *m_manager;
}
Then in request.cpp you can do it like here:
Request::Request(QObject *parent): QObject(parent) {
m_manager = new QNetworkAccessManager(this);
QObject::connect(m_manager, SIGNAL(finished(QNetworkReply*)),
this, SLOT(replyFinished(QNetworkReply *)));
}
Request::~Request() {
delete m_manager;
}
void Request::replyFinished(QNetworkReply *reply) {
//do_something
}
Then you can use it like here:
Request *handle = new Request():
handle->do_some_methods();
//...etc