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POQt can I connect signals/slots to self in constructor?
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  1. POQt can I connect signals/slots to self in constructor?
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    copied!<p>EDIT: Not related to signals/slots/connect. Problem was constructor calling constructor.</p> <p>There might be a better way to do this - I'd be interested in hearing those...</p> <p>I have MyClass that is derived from a QLabel. I want to pass more data about the derived class back in the signal than what the base signal does. So I made a slot to intercept the customContextMenuRequested signal and emit a revised one that has more data.</p> <p>When I try to connect up this signal in the constructor, then my slot never gets called. But if I move the Policy and connect lines out to the parent widget(not class hierarchy parent) so they execute after MyClass is fully constructed, then my slot will get called. But I always want that to be connected for this class and it seems like something I would want in it's constructor rather than counting on the parent class to remember to do it.</p> <p>Is there something I'm doing wrong? Or a better way to add data to a signal?</p> <pre><code>MyClass::MyClass() : QLabel() { QFont currFont = font(); currFont.setPointSize(15); setFont(currFont); setBackgroundRole(QPalette::Mid); std::cout &lt;&lt; "connecting customContextMenuRequested" &lt;&lt; std::endl; /** PROBLEM START */ setContextMenuPolicy(Qt::CustomContextMenu); // Is there anything wrong with connecting from "this" to "this" in a constructor? QObject::connect(this, SIGNAL(customContextMenuRequested(const QPoint&amp;)), this, SLOT(addCellDataToMenuContextRequest(const QPoint&amp;))); /* PROBLEM END **/ } MyClass::MyClass(QString &amp;cellString, int row, int col) : QLabel(cellString) { MyClass(); setRow(row); setCol(col); } // This one is a slot void MyClass::addCellDataToMenuContextRequest(const QPoint&amp; pos) { // This doesn't get printed if I connect in my constructor, // but it does print if I do the same connect from a parent widget. std::cout &lt;&lt; "called addCellDataToMenuContextRequest" &lt;&lt; std::endl; emit customContextMenuRequestedForCell(pos, _row, _col); } </code></pre> <p>So I would like the parent widget to just look for customContextMenuRequestedForCell but right now, the parent widget seems to need to be responsible for customContextMenuRequested as well.</p>
 

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