擴展 QML - 添加類型範例

導齣 C++ 類。

The Adding Types Example shows how to add a new object type, Person , to QML. The Person type can be used from QML like this:

import People 1.0
Person {
    name: "Bob Jones"
    shoeSize: 12
}

聲明 Person 類

All QML types map to C++ types. Here we declare a basic C++ Person class with the two properties we want accessible on the QML type - name and shoeSize. Although in this example we use the same name for the C++ class as the QML type, the C++ class can be named differently, or appear in a namespace.

class Person : public QObject
{
    Q_OBJECT
    Q_PROPERTY(QString name READ name WRITE setName)
    Q_PROPERTY(int shoeSize READ shoeSize WRITE setShoeSize)
    QML_ELEMENT
public:
    Person(QObject *parent = nullptr);
    QString name() const;
    void setName(const QString &);
    int shoeSize() const;
    void setShoeSize(int);
private:
    QString m_name;
    int m_shoeSize;
};

定義 Person 類

Person::Person(QObject *parent)
: QObject(parent), m_shoeSize(0)
{
}
QString Person::name() const
{
    return m_name;
}
void Person::setName(const QString &n)
{
    m_name = n;
}
int Person::shoeSize() const
{
    return m_shoeSize;
}
void Person::setShoeSize(int s)
{
    m_shoeSize = s;
}

The Person class implementation is quite basic. The property accessors simply return members of the object instance.

運行範例

The main.cpp file in the example includes a simple shell application that loads and runs the QML snippet shown at the beginning of this page.

範例工程 @ code.qt.io