QMap<int, QString> intToStr; intToStr[] = "test" for (auto iter = intToStr.begin(); iter != intToStr.end(); ++iter) { //int aa = *iter; QString two = iter.value(); QString test = *iter;//对迭代器解引用是返回value值,按我的理解迭代器应该指向的是那一对数据啊 }
一般情况下信号槽直接连接方式不会出现问题,但是如果信号与槽在不同线程或Qt::QueuedConnection方式连接,可能会在连接期间报以下类似问题,如: QObject::connect: Cannot queue arguments of type 'ThreadSignal' (Make sure 'ThreadSignal' is registered using qRegisterMetaType().) 或者 QObject::connect: Cannot queue argum
QMap vs. QHash: A small benchmark While working on my Qt developer days 2012 presentation (QtCore in depth), I made a benchmark comparing QMap and QHash. I thought it would be nice to share the results in this short blog entry. Under The Hood The Qt
QObject::connect: Cannot queue arguments of type 'QMap<QString,QString>',(Make sure 'QMap<QString,QString>' is registered using qRegisterMetaType().). 上述错误,只有在跨线程信号传递时才会出现. 因为QMap是QT可识别的基本类型,不需要再注册元对象系统中,在同一个线程中运行没有问题. 源码: // 线程类 thread.h cla