COM App Example (ActiveQt)▲
class
Application : public
QObject
{
Q_OBJECT
Q_CLASSINFO("ClassID"
, "{b50a71db-c4a7-4551-8d14-49983566afee}"
)
Q_CLASSINFO("InterfaceID"
, "{4a427759-16ef-4ed8-be79-59ffe5789042}"
)
Q_CLASSINFO("RegisterObject"
, "yes"
)
Q_PROPERTY(DocumentList*
documents READ documents)
Q_PROPERTY(QString id READ id)
Q_PROPERTY(bool
visible READ isVisible WRITE setVisible)
public
:
explicit
Application(QObject *
parent =
nullptr
);
DocumentList *
documents() const
;
QString id() const
{
return
objectName(); }
void
setVisible(bool
on);
bool
isVisible() const
;
QTabWidget *
window() const
{
return
m_ui.data(); }
public
slots:
void
quit();
private
:
QScopedPointer &
lt;DocumentList&
gt; m_docs;
QScopedPointer &
lt;QTabWidget&
gt; m_ui;
}
;
The first class Application represents the application object. It exposes read-only properties documents and id to get access to the list of documents, and an identifier. A read/write property visible controls whether the QTabWidget-based user interface of the application should be visible, and a slot quit() terminates the application.
The RegisterObject attribute is set to make sure that instances of this class are registered in COM's running object table (ROT) - this allows COM clients to connect to an already instantiated COM object.
class
DocumentList : public
QObject
{
Q_OBJECT
Q_CLASSINFO("ClassID"
, "{496b761d-924b-4554-a18a-8f3704d2a9a6}"
)
Q_CLASSINFO("InterfaceID"
, "{6c9e30e8-3ff6-4e6a-9edc-d219d074a148}"
)
Q_PROPERTY(Application*
application READ application)
Q_PROPERTY(int
count READ count)
public
:
explicit
DocumentList(Application *
application);
int
count() const
;
Application *
application() const
;
public
slots:
Document *
addDocument();
Document *
item(int
index) const
;
private
:
QList&
lt;Document *&
gt; m_list;
}
;
The DocumentList class stores a list of documents. It provides an API to read the number of documents, to access each document by index and to create a new document. The application property returns the root object.
class
Document : public
QObject
{
Q_OBJECT
Q_CLASSINFO("ClassID"
, "{2b5775cd-72c2-43da-bc3b-b0e8d1e1c4f7}"
)
Q_CLASSINFO("InterfaceID"
, "{2ce1761e-07a3-415c-bd11-0eab2c7283de}"
)
Q_PROPERTY(Application *
application READ application)
Q_PROPERTY(QString title READ title WRITE setTitle)
public
:
explicit
Document(DocumentList *
list);
virtual
~
Document();
Application *
application() const
;
QString title() const
;
void
setTitle(const
QString &
amp;title);
private
:
QScopedPointer &
lt;QWidget&
gt; m_page;
}
;
The Document class finally represents a document in the application. Each document is represented by a page in the application's tab widget, and has a title that is readable and writable through the document's API. The application property again returns the root object.
Document::
Document(DocumentList *
list)
:
QObject(list)
{
QTabWidget *
tabs =
list-&
gt;application()-&
gt;window();
m_page.reset(new
QWidget(tabs));
m_page-&
gt;setWindowTitle(tr("Unnamed"
));
tabs-&
gt;addTab(m_page.data(), m_page-&
gt;windowTitle());
m_page-&
gt;show();
}
Document::
~
Document()
{
}
Application *
Document::
application() const
{
return
qobject_cast&
lt;DocumentList *&
gt;(parent())-&
gt;application();
}
QString Document::
title() const
{
return
m_page-&
gt;windowTitle();
}
void
Document::
setTitle(const
QString &
amp;t)
{
m_page-&
gt;setWindowTitle(t);
QTabWidget *
tabs =
application()-&
gt;window();
int
index =
tabs-&
gt;indexOf(m_page.data());
tabs-&
gt;setTabText(index, m_page-&
gt;windowTitle());
}
The implementation of the Document class creates a new page for the tab widget, and uses the title of that page for the title property. The page is deleted when the document is deleted.
DocumentList::
DocumentList(Application *
application)
:
QObject(application)
{
}
Application *
DocumentList::
application() const
{
return
qobject_cast&
lt;Application *&
gt;(parent());
}
int
DocumentList::
count() const
{
return
m_list.count();
}
Document *
DocumentList::
item(int
index) const
{
return
m_list.value(index, nullptr
);
}
Document *
DocumentList::
addDocument()
{
Document *
document =
new
Document(this
);
m_list.append(document);
return
document;
}
The DocumentList implementation is straightforward.
Application::
Application(QObject *
parent)
:
QObject(parent),
m_ui(new
QTabWidget),
m_docs(new
DocumentList(this
))
{
setObjectName(QStringLiteral("From QAxFactory"
));
}
DocumentList *
Application::
documents() const
{
return
m_docs.data();
}
void
Application::
setVisible(bool
on)
{
m_ui-&
gt;setVisible(on);
}
bool
Application::
isVisible() const
{
return
m_ui-&
gt;isVisible();
}
void
Application::
quit()
{
m_docs.reset();
m_ui.reset();
QTimer::
singleShot(0
/*ms*/
, qApp, &
amp;QCoreApplication::
quit);
}
#include
"main.moc"
The Application class initializes the user interface in the constructor, and shows and hides it in the implementation of setVisible(). The object name (accessible through the id property) is set to "From QAxFactory" to indicate that this COM object has been created by COM. Note that there is no destructor that would delete the QTabWidget - this is instead done in the quit() slot, before calling quit() through a single-shot-timer, which is necessary to ensure that the COM call to the slot is complete.