Qt QList <T> casts and node_copy
I will catch the error and have no idea how to fix it. I am making a combobox selector for available SQLDrivers (providers).
Title
#include "QObject"
#include "QString"
#include "QList"
#include "QPointer"
class TProvider;
typedef const TProvider * const TProviderPointer;
class TProvider
{
public:
QString name;
QString driverName;
TProvider(QString name, QString driverName);
static const QList<TProviderPointer> getAvailableProviders();
static TProviderPointer getProvider(int id);
};
TProviderPointer MySQLProvider = new TProvider("MySQL", "QMYSQL");
TProviderPointer IBProvider = new TProvider("Interbase", "QIBASE");
CPP. Here I am creating two constant pointers to const Providers (TProviderPointer) (listing the available drivers). And I have a method that returns const QList.
#include "tprovider.h"
TProvider::TProvider(QString name, QString driverName):
name(name), driverName(driverName)
{
}
const QList<TProviderPointer> TProvider::getAvailableProviders()
{
QList<TProviderPointer> list;
list.append(MySQLProvider);
list.append(IBProvider);
return list;
}
TProviderPointer getProvider(int id)
{
switch(id){
case 0:
return MySQLProvider;
case 1:
return IBProvider;
}
}
when i use this
const QList<TProviderPointer> list = TProvider::getAvailableProviders();
foreach (TProviderPointer provider, list) {
ui->eprovider->addItem(provider->name);
}
I get and point an error to qlist.h and line - const QList<TProviderPointer> list = TProvider::getAvailableProviders();
> C2440 TProviderPointer *
before void *
:
Q_INLINE_TEMPLATE void QList<T>::node_copy(Node *from, Node *to, Node *src)
Do I have a copy operation to use? How can I fix this? Thank.
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I think the problem is with your typedef. const TProvider * const
is a pointer to const TProvider
, but in your code, you create new instances TProvider
at runtime. Also you can read in the Qt documentation about QList that:
The QList value type must be an assignable data type.
So, you should have a pointer to TProvider
, and your typedef should look like this:
typedef const TProvider * TProviderPointer;
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