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POElement is removed from QList but static counter of existing objects doesn't decrease
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  1. POElement is removed from QList but static counter of existing objects doesn't decrease
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    copied!<p>I have question about removing element from QList.</p> <p>"myclass.h":</p> <pre><code>class node2D : public QObject { Q_OBJECT public: node2D(){++s_NCount;}; ~node2D(){--s_NCount;}; int checkCount(){return s_NCount;}; private: static int s_NCount; }; </code></pre> <p>"myclass.cpp":</p> <pre><code>int node2D::s_NCount = 0; </code></pre> <p>"main.cpp":</p> <pre><code>void main() { int i,max_el(4); QList&lt;node2D*&gt; *Nlist; Nlist = new QList&lt;node2D*&gt;; node2D controlNode; for (i = 0 ;i &lt; max_el ; i++) { Nlist-&gt;append(new node2D); } cout &lt;&lt; "Nlist size before: " &lt;&lt; Nlist-&gt;size() &lt;&lt; endl; cout &lt;&lt; "Number of nodes before removing: " &lt;&lt; controlNode.checkCount() &lt;&lt; endl; Nlist-&gt;clear(); cout &lt;&lt; "NList size after: " &lt;&lt; Nlist-&gt;size() &lt;&lt; endl; delete Nlist; cout &lt;&lt; "Number of nodes after removing: " &lt;&lt; controlNode.checkCount() &lt;&lt; endl; } </code></pre> <p>After executing I get:</p> <ul> <li>NList size before: 4</li> <li>Number of nodes before removing: 5</li> <li>NList size after: 0</li> <li>Number of nodes after removing: 5</li> </ul> <p>What's bothering me is the fact that number of node2D objects is still 5 instead of 1. </p> <p>Of course it can be managed like this:</p> <pre><code>for (i = 0; i &lt; Nlist-&gt;size(); i++) { delete (*Nlist)[i]; } Nlist-&gt;clear(); </code></pre> <p>but shouldn't node2D objects be automatically deleted while Nlist->clear()? </p> <p><strong>Or does it only happen when there is parent-child relation?</strong></p> <p>Thanks in advance,</p> <p>Pawel</p>
 

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