KMimeTypeTrader Class Reference

KDE's trader for services associated to a given mimetype. More...

#include <kmimetypetrader.h>

List of all members.

Public Member Functions
	~KMimeTypeTrader ()
KService::Ptr	preferredService (const QString &mimeType, const QString &genericServiceType=QString::fromLatin1("Application"))
KService::List	query (const QString &mimeType, const QString &genericServiceType=QString::fromLatin1("Application"), const QString &constraint=QString()) const
Static Public Member Functions
template<class T >
static T *	createInstanceFromQuery (const QString &mimeType, const QString &serviceType, QObject *parent=0, const QString &constraint=QString(), const QVariantList &args=QVariantList(), QString *error=0)
template<class T >
static T *	createPartInstanceFromQuery (const QString &mimeType, QWidget *parentWidget=0, QObject *parent=0, const QString &constraint=QString(), const QVariantList &args=QVariantList(), QString *error=0)
static KMimeTypeTrader *	self ()

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Detailed Description

KDE's trader for services associated to a given mimetype.

Example: say that you want to the list of all KParts components that can handle HTML. Our code would look like:

 KService::List lst = KMimeTypeTrader::self()->query("text/html",
                                                        "KParts/ReadOnlyPart");

If you want to get the preferred KParts component for text/html you could use preferredService("text/html", "KParts/ReadOnlyPart"), although if this is about loading that component you would use createPartInstanceFromQuery directly.

See also:

KServiceTypeTrader, KService

Definition at line 42 of file kmimetypetrader.h.

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Constructor & Destructor Documentation

KMimeTypeTrader::~KMimeTypeTrader

(

)

Standard destructor.

Definition at line 49 of file kmimetypetrader.cpp.

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Member Function Documentation

template<class T >

static T* KMimeTypeTrader::createInstanceFromQuery	(	const QString &	mimeType,
		const QString &	serviceType,
		QObject *	parent = 0,
		const QString &	constraint = QString(),
		const QVariantList &	args = QVariantList(),
		QString *	error = 0
	)		[inline, static]

This can be used to create a service instance from a mime type query.

Parameters:

mimeType	A mime type like 'text/plain' or 'text/html'.
serviceType	a basic service type
parent	the parent object for the plugin itself
constraint	A constraint to limit the choices returned, QString() to get all services that can handle the given mimetype
args	A list of arguments passed to the service component
error	The string passed here will contain an error description.

Returns:

A pointer to the newly created object or a null pointer if the factory was unable to create an object of the given type.

Definition at line 154 of file kmimetypetrader.h.

template<class T >

static T* KMimeTypeTrader::createPartInstanceFromQuery	(	const QString &	mimeType,
		QWidget *	parentWidget = 0,
		QObject *	parent = 0,
		const QString &	constraint = QString(),
		const QVariantList &	args = QVariantList(),
		QString *	error = 0
	)		[inline, static]

This method creates and returns a part object from the trader query for a given mimeType.

Example:

 KParts::ReadOnlyPart* part = KMimeTypeTrader::createInstanceFromQuery<KParts::ReadOnlyPart>("text/plain", parentWidget, parentObject);
 if (part) {
     part->openUrl(url);
     part->widget()->show();  // also insert the widget into a layout, or simply use a KVBox as parentWidget
 }

Parameters:

mimeType	the mimetype which this part is associated with
parentWidget	the parent widget, will be set as the parent of the part's widget
parent	the parent object for the part itself
constraint	an optional constraint to pass to the trader
args	A list of arguments passed to the service component
error	The string passed here will contain an error description.

Returns:

A pointer to the newly created object or a null pointer if the factory was unable to create an object of the given type.

Definition at line 121 of file kmimetypetrader.h.

KService::Ptr KMimeTypeTrader::preferredService	(	const QString &	mimeType,
		const QString &	genericServiceType = QString::fromLatin1("Application")
	)

Returns the preferred service for mimeType and genericServiceType.

This is almost like query().first(), except that it also checks if the service is allowed as a preferred service (see KService::allowAsDefault).

Parameters:

mimeType	the mime type (see query())
genericServiceType	the service type (see query())

Returns:

the preferred service, or 0 if no service is available

Definition at line 157 of file kmimetypetrader.cpp.

KService::List KMimeTypeTrader::query	(	const QString &	mimeType,
		const QString &	genericServiceType = QString::fromLatin1("Application"),
		const QString &	constraint = QString()
	)		const

This method returns a list of services which are associated with a given mimetype.

Example usage: To get list of applications that can handle a given mimetype, set genericServiceType to "Application" (which is the default). To get list of embeddable components that can handle a given mimetype, set genericServiceType to "KParts/ReadOnlyPart".

The constraint parameter is used to limit the possible choices returned based on the constraints you give it.

The constraint language is rather full. The most common keywords are AND, OR, NOT, IN, and EXIST, all used in an almost spoken-word form. An example is:

 (Type == 'Service') and (('Browser/View' in ServiceTypes) and (exist Library))

The keys used in the query (Type, ServiceTypes, Library) are all fields found in the .desktop files.

Parameters:

mimeType	A mime type like 'text/plain' or 'text/html'.
genericServiceType	a basic service type, like 'KParts/ReadOnlyPart' or 'Application'
constraint	A constraint to limit the choices returned, QString() to get all services that can handle the given mimetype

Returns:

A list of services that satisfy the query, sorted by preference (preferred service first)

See also:

http://techbase.kde.org/Development/Tutorials/Services/Traders#The_KTrader_Query_Language

Definition at line 142 of file kmimetypetrader.cpp.

KMimeTypeTrader * KMimeTypeTrader::self

(

)

[static]

This is a static pointer to the KMimeTypeTrader singleton.

You will need to use this to access the KMimeTypeTrader functionality since the constructors are protected.

Returns:

Static KMimeTypeTrader instance

Definition at line 38 of file kmimetypetrader.cpp.

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The documentation for this class was generated from the following files:

• kmimetypetrader.h
• kmimetypetrader.cpp