Qt5 official demo release set 21 -- extending qml-adding types example

All articles in this series can be viewed here in http://blog.csdn.net/cloud_castle/article/category/2123873

It is a new series, but this series is similar to our previous chapter series. However, chapter mainly demonstrates how to use C ++ to create a type with visibility to expand our qml, and this series focuses on how to use C ++ to expand qml non-visualized content.

The first small example here is similar to the first small example of chapter:

Person is our custom C ++ class, and then we register it as the qml type for example. qml in the resource file.

Person. H. This class is not much different from the previous piechart:

# Ifndef person_h # define person_h # include <qobject> //! [0] class person: Public qobject // note that this object does not need to be visualized, we can inherit the most basic qobject. {q_object // because the qml component is based on the metadata system, neither qobject nor q_object can be less than q_property (qstring name read name write setname) // two Custom Attributes q_property (INT shoesize read shoesize write setshoesize) Public: Person (qobject * parent = 0); qstring name () const; void setname (const qstring &); int shoesize () const; void setshoesize (INT); Private: qstring m_name; Int m_shoesize ;};//! [0]

Person. cpp:

#include "person.h"// ![0]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;}

Example. qml:

Import people 1.0 person {// non-visualized component, and we no longer need to use item as the parent Object Name: "Bob Jones" shoesize: 12}

Main. cpp:

# Include <qcoreapplication> // note that qguiapplication # include <qqmlengine> in chapter provides the running environment of qml components # include <qqmlcomponent> // encapsulate and access qml components # include <qdebug> # include "person. H "int main (INT argc, char ** argv) {qcoreapplication app (argc, argv );//! [0] qmlregistertype <person> ("people", "person"); // register the qml type //! [0] qqmlengine engine; qqmlcomponent (& engine, qurl ("qrc: Example. qml "); // obtain the component person * person = qobject_cast <person *> (component. create (); // create the instantiated object of this component if (person) {qwarning () <"the person's name is" <person-> name (); // still access its member function qwarning () <"they wear a" <person-> shoesize () <"sized shoe ";} else {qwarning () <component. errors (); // if the type conversion fails, the error message is returned.} return 0 ;}

Because there is no interface, the actual operation is the output of a single console: