The standard C++ object model provides very efficient runtime support for the object paradigm. But its static nature is inflexibile in certain problem domains. Graphical user interface programming is a domain that requires both runtime efficiency and a high level of flexibility. Qt provides this, by combining the speed of C++ with the flexibility of the Qt Object Model.
Qt 把这些特征添加到 C++:
Many of these Qt features are implemented with standard C++ techniques, based on inheritance from QObject . Others, like the object communication mechanism and the dynamic property system, require the 元对象系统 provided by Qt's own MOC (元对象编译器) .
The meta-object system is a C++ extension that makes the language better suited to true component GUI programming.
这些类形成 Qt 对象模型的基础。
有关类的额外信息 | |
有关枚举器的元数据 | |
关于成员函数的元数据 | |
包含有关 Qt 对象的元信息 | |
关于特性的元数据 | |
在元对象系统中管理命名类型 | |
所有 Qt 对象的基类 | |
看守多个 QObject 的寿命 | |
提供指向 QObject 守卫指针的模板类 | |
围绕 QObject::blockSignals() 的异常安全包裹器 | |
捆绑来自可识别发送器的信号 | |
举动像最常见 Qt 数据类型的并集 |
Some of the added features listed above for the Qt Object Model, require that we think of Qt Objects as identities, not values. Values are copied or assigned; identities are cloned. Cloning means to create a new identity, not an exact copy of the old one. For example, twins have different identities. They may look identical, but they have different names, different locations, and may have completely different social networks.
Then cloning an identity is a more complex operation than copying or assigning a value. We can see what this means in the Qt Object Model.
Qt 对象 ...
For these reasons, Qt Objects should be treated as identities, not as values. Identities are cloned, not copied or assigned, and cloning an identity is a more complex operation than copying or assigning a value. Therefore, QObject and all subclasses of QObject (direct or indirect) have their 拷贝构造函数和赋值运算符 disabled.