在作为QList的QVariant上迭代< int> [英] Iterating over a QVariant that is a QList<int>?

问题描述

我使用QObject的动态属性来存储要在可以访问所述属性的插槽中使用的信息。发送者是一个QState，具有： myQState-> setProperty（key，QList< int>（0,1,2））;

I'm using QObject's dynamic property to store information to be used in a Slot that can access said property. The sender is a QState with: myQState->setProperty("key", QList<int>(0, 1, 2));

我要转换存储的 QVariant 返回一个QList，所以它可以迭代。以下代码不工作（错误C2440：QVariant无法转换为与{[T = int]）的QList：

I would like to convert the stored QVariant back to a QList so it can be iterated. The following code does not work (error C2440: QVariant can't be converted to QList with {[T=int]):

QVariant vprop = obj->property("key");
QList<int> list = vprop; //   < - - - - - - - - ERROR
foreach (int e, list )
{
    qDebug() << __FUNCTION__ << "" << e;
}

---

设置为属性的对象：

---

This code works. The object to set as property:

QVariantList list;
list.append(0);
list.append(1);
list.append(2);

并在插槽

QObject *obj = this->sender();
foreach( QByteArray dpn, obj->dynamicPropertyNames() )
{
    qDebug() << __FUNCTION__ << "" << dpn;
}
QVariant vprop = obj->property("key");
qDebug() << __FUNCTION__ << "" << vprop;
QVariantList list = vprop.toList();
foreach(QVariant e, list )
{
    qDebug() << __FUNCTION__ << "" << e.toInt();
}

推荐答案

c> QList< QVariant> QVariant :: toList（）const

Or use QList<QVariant> QVariant::toList () const

QList<QVariant> list = vprop.toList();

而不是遍历这些项目，并根据需要将其转换为整数。

And than iterate over the items and convert each to integer if needed.

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