use of undeclared identifier 'connect'

Question

I'm trying to write a simple downloader in qt. It's based on this example: http://www.ggkf.com/qt/qnetworkrequest-to-download-an-image

downloader.cpp:

void Downloader::GetImage( QString _url, QNetworkAccessManager *qnam ) {
    connect( qnam, SIGNAL( finished( QNetworkReply *) ), this, SLOT( replyFinished(   QNetworkReply * ) ) );

    QUrl url = QUrl( _url );
    QNetworkRequest request( url );

    qnam->get( request );
}

But I get the following error:

/Users/name/ssl/downloader.cpp:19: error: use of undeclared identifier 'connect'
connect( qnam, SIGNAL( finished( QNetworkReply *) ), this, SLOT( replyFinished( QNetworkReply * ) ) );

Can anyone of you explain to me this error?

Are you missing a header file inclusion? – Moo-Juice Nov 12 '13 at 09:40 — Moo-Juice, Nov 12 '13 at 09:40
Downloader does probably not inherit from QObject? It must. – Frank Osterfeld Nov 12 '13 at 09:42 — Frank Osterfeld, Nov 12 '13 at 09:42
Thanks you two. It was the missing inheritance. – btzs Nov 13 '13 at 10:07 — btzs, Nov 13 '13 at 10:07

score 14 · Accepted Answer · answered Jan 19 '15 at 12:26

14

please ensure Downloader does inherit from QObject.

class Downloader : public QObject{

}

answered Jan 19 '15 at 12:26

Ryeeeeee

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@LorenzMeyer, yes, but this is a common issue faced by Qt newbies, and thus deserves an answer on its own, even if it was given in the comment. – SexyBeast Mar 11 '15 at 12:03
Just because it's old, doesn't (always) make it incorrect -- it's the first answer that pops up on google, and has immediately given me the correct answer. – Anonymouse Nov 01 '18 at 15:35

use of undeclared identifier 'connect'

1 Answers1