C++ 将信号连接到c++；QT5中的11个lambdas

我尝试将QDoubleSpinBox信号连接到c++11 lamda：

QObject::connect(sbox_roughness, &QDoubleSpinBox::valueChanged,
               [=]() { std::cout << "value changed" << std::endl; });

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我在这里遗漏了什么？

你面临着不匹配的争论。应该是这样的：

QObject::connect(sbox_roughness, static_cast<void(QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
           [=](double val) { std::cout << "value changed" << std::endl; });

QObject:：connect（sbox\u粗糙度、静态\u投射（&QDoubleSpinBox:：valueChanged），
[=]（双val）{std:：cout
此操作失败，因为
QDoubleSpinBox
没有
valueChanged（int）
信号

这将有助于：

QObject::connect(&spinbox, static_cast<void (QDoubleSpinBox::*)(double)>(
                                  &QDoubleSpinBox::valueChanged),
                []() {  qDebug() << "value changed"; });

QObject::connect(&spinbox, static_cast<void (QDoubleSpinBox::*)(const QString &)>(
                                  &QDoubleSpinBox::valueChanged),
                []() {  qDebug() << "value changed"; });

QObject:：连接（&spinbox），静态\u转换(
&QDoubleSpinBox:：valueChanged），
[]（）{qDebug（）您的答案已将它们更改为我的答案。当然，它不适用于：（QDoubleSpinBox:：*）（int）>（&QDoubleSpinBox:：valueChanged）。很抱歉监督此操作！回答正确！
error: no matches converting function ‘valueChanged’ to type ‘void (class QDoubleSpinBox::*)(int)’
                                    &QDoubleSpinBox::valueChanged),

QObject::connect(sbox_roughness, static_cast<void(QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
           [=](double val) { std::cout << "value changed" << std::endl; });

QDoubleSpinBox spinbox;

QObject::connect(&spinbox, &QDoubleSpinBox::valueChanged,
                 []() { qDebug() << "value changed"; });

QObject::connect(&spinbox, static_cast<void (QDoubleSpinBox::*)(int)>(
                                  &QDoubleSpinBox::valueChanged),
                []() {  qDebug() << "value changed"; });

QObject::connect(&spinbox, static_cast<void (QDoubleSpinBox::*)(double)>(
                                  &QDoubleSpinBox::valueChanged),
                []() {  qDebug() << "value changed"; });

QObject::connect(&spinbox, static_cast<void (QDoubleSpinBox::*)(const QString &)>(
                                  &QDoubleSpinBox::valueChanged),
                []() {  qDebug() << "value changed"; });