Using MSVC 2010, Win 7 (64), Qt 4.8.4. I’m pretty sure I just got some parameter types wrong, but I just fail to see which… ? I’d also be grateful for hints to better solutions of this problem (teaching a class how to write itself to an XML file).
#include <QtXML>
class base {
public:
virtual QDomElement& Write(QDomDocument& doc) {
QDomElement& de = doc.createElement("Element1");
de.setAttribute("Attr1", "Value1");
return de;
}
};
class derived : public base {
public:
QDomElement& Write(QDomDocument& doc) {
QDomElement& de = base::Write(doc);
de.setAttribute("Attr2", 2);
return de;
}
};
int main(int argc, char *argv[])
{
QDomDocument doc("testtype");
QDomElement root = doc.createElement("test");
doc.appendChild(root);
//#define crash 1
#ifdef crash
// IMO using these two classes should result in
// the exact same calls as the positive case below
base t1;
derived t2;
root.appendChild(t1.Write(doc));
root.appendChild(t2.Write(doc));
#else
// This is the positive case - no classes involved
QDomElement& de = doc.createElement("Element1");
de.setAttribute("Attr1", "Value1");
root.appendChild(de);
de = doc.createElement("Element1");
de.setAttribute("Attr1", "Value1");
de.setAttribute("Attr2", 2);
root.appendChild(de);
#endif
QFile of("test.xml");
if (!of.open(QIODevice::WriteOnly))
return 1;
QTextStream ts(&of);
ts << doc.toString();
of.close();
return 0;
}
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