Qt5 official demo release set 28 -- extending qml-signal support example

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

Link to qt5 official demo release set 27 -- extending qml-Attached properties example

This demo demonstrates how to add signals for the qml custom type, which is similar to what qt5 official demo consumer set 16 -- Chapter 2: connecting to C ++ methods and signals introduces, given the size of the example, the article may be clearer.

In any case, we still need to extend this birthdayparty routine. We added a "party start" signal for this birthday party and defined a function to send this signal.

Since the person class remains unchanged, let's look at the changed birthdayparty. h:

# Ifndef birthdayparty_h # define birthdayparty_h # include <qobject> # include <qdate> # include <qqml. h> # include "person. H "class birthdaypartyattached: Public qobject {q_object q_property (qdate RSVP read RSVP write setrsvp) Public: birthdaypartyattached (qobject * object); qdate RSVP () const; void setrsvp (const qdate &); Private: qdate m_rsvp;}; Class birthdayparty: Public qobject {q_object q_property (person * Host read host write sethost) q_property (qqmllistproperty <person> guests read guests) q_classinfo ("defaultproperty", "guests") Public: birthdayparty (qobject * parent = 0 ); person * Host () const; void sethost (person *); qqmllistproperty <person> guests (); int guestcount () const; person * guest (INT) const; static birthdaypartyattached * qmlattachedproperties (qobject *); void startparty (); // custom function. Q_invokable is used because the function is called in Main. cpp instead of qml //! [0] signals: void partystarted (const qtime & time); // custom signal //! [0] private: person * m_host; qlist <person *> m_guests;}; qml_declare_typeinfo (birthdayparty, qml_has_attached_properties) # endif // birthdayparty_h

Birthdayparty. cpp:

# Include "birthdayparty. H "birthdaypartyattached: birthdaypartyattached (qobject * object): qobject (object) {} qdate response: RSVP () const {return m_rsvp;} void birthdaypartyattached :: setrsvp (const qdate & D) {m_rsvp = D;} birthdayparty: birthdayparty (qobject * parent): qobject (parent), m_host (0) {} person * birthdayparty :: host () const {return m_host;} void birthdayparty: sethost (person * c) {m_host = C;} qqmllistproperty <person> birthdayparty: Guests () {return qqmllistproperty <person> (this, m_guests);} int birthdayparty: guestcount () const {return m_guests.count ();} person * birthdayparty: Guest (INT index) const {return m_guests.at (INDEX);} void birthdayparty: startparty () // This function is used to transmit the current time as a signal parameter {qtime time = qtime: currenttime (); emit partystarted (time);} birthdaypartyattached * birthdayparty: qmlattachedproperties (qobject * object) {return New birthdaypartyattached (object );}

Example. qml:

Import people 1.0 import qtquick 2.0 // For qcolorbirthdayparty {//! [0] onpartystarted: console. Log ("this party started rockin 'At" + time); // In qml, we do not need to process the signal //! [0] // you only need to pay attention to the onxxx function corresponding to the signal. // when the signal is sent, the function is executed HOST: Boy {name: "Bob Jones" shoe {size: 12; color: "white"; Brand: "Nike"; Price: 90.0} Boy {name: "Leo Hodge" birthdayparty. RSVP: "2009-07-06" shoe {size: 10; color: "black"; Brand: "Reebok"; Price: 59.95} Boy {name: "Jack Smith" shoe {size: 8; color: "blue"; Brand: "Puma"; Price: 19.95} girl {name: "Anne Brown" birthdayparty. RSVP: "200 9-07-01 "shoe. Size: 7 shoe. Color:" red "shoe. Brand:" Marc jacbs "shoe. Price: 699.99 }//! [1]} //! [1]

Main. cpp:

# Include <qcoreapplication> # include <qqmlengine> # include <qqmlcomponent> # include <qdebug> # include "birthdayparty. H "# include" person. H "int main (INT argc, char ** argv) {qcoreapplication app (argc, argv); qmlregistertype <birthdaypartyattached> (); qmlregistertype <birthdayparty> (" people ", 1,0, "birthdayparty"); qmlregistertype <shoedescription> (); qmlregistertype <person> (); qmlregistertype <boy> ("people ",, "Boy"); qmlregistertype <girl> ("people", "girl"); qqmlengine engine; qqmlcomponent component (& engine, qurl ("qrc: Example. qml "); birthdayparty * party = qobject_cast <birthdayparty *> (component. create (); If (party & party-> host () {qwarning () <party-> host ()-> name () <"is having a birthday! "; If (qobject_cast <boy *> (Party-> host () qwarning () <" He is inviting: "; else qwarning () <"she is inviting:"; for (int ii = 0; II <party-> guestcount (); ++ II) {person * guest = party-> guest (II); qdate rsvpdate; qobject * attached = qmlattachedpropertiesobject <birthdayparty> (guest, false); If (attached) rsvpdate = attached-> property ("RSVP "). todate (); If (rsvpdate. isnull () qwarning () <"" <guest-> name () <"RSVP date: hasn't RSVP 'd"; else qwarning () <"" <guest-> name () <"RSVP date:" <qprintable (rsvpdate. tostring (); // qprintable is discussed above} party-> startparty (); // The transmit signal function is called here, therefore, the start time of the party will be printed on the last line} else {qwarning () <component. errors ();} return 0 ;}

Result