Development/Tutorials/Services/Traders - Revision history

AnneW at 09:15, 14 July 2012

2012-07-14T09:15:08Z

Icwiener: Fix syntax highlighting.

2011-06-27T15:26:34Z

Fix syntax highlighting.

Yecril71pl: /* String Matching Operators */ ktraderclient

2010-11-30T10:39:45Z

‎String Matching Operators: ktraderclient

Dipesh: /* Identifiers */

2008-12-10T03:08:48Z

‎Identifiers

Aseigo: /* String Matching Operators */

2008-02-25T03:23:22Z

‎String Matching Operators

Dhaumann: nitpick ;)

2007-11-21T19:53:29Z

nitpick ;)

DrSlowDecay: Language Navigation added

2007-11-20T15:02:57Z

Language Navigation added

Travlr: fixed typo

2007-09-26T18:36:58Z

fixed typo

Travlr: fixed grammer

2007-09-26T18:34:50Z

fixed grammer

Travlr: fixed grammer

2007-09-26T18:10:30Z

fixed grammer

← Older revision		Revision as of 09:15, 14 July 2012
Line 1:		Line 1:
−	~~{{Template:I18n/Language Navigation Bar\|Development/Tutorials/Services/Traders}}~~	+

	{{TutorialBrowser\|		{{TutorialBrowser\|

@@ Line 50: / Line 50: @@
 The code to do this is very straight forward:
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 KService::List services;
 KServiceTypeTrader* trader = KServiceTypeTrader::self();
@@ Line 68: / Line 68: @@
      kDebug() << "no preferred service found for KDevelop/Plugin";
+}
-</code>
+</syntaxhighlight>
 In each case zero or more services are returned that are now usable for locating, describing and loading the item it represents.
@@ Line 78: / Line 78: @@
 The query language itself is designed to be human readable and flexible. <tt>{{class|KServiceTypeTrader}}::query</tt> optionally takes a query, in addition to the service type, and uses that to provide more fine-grained searches. So, for example, we'll modify the earlier example in the following way:
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 KService::List services ;
 KServiceTypeTrader* trader = KServiceTypeTrader::self();
@@ Line 90: / Line 90: @@
      kDebug() << "read write part" << service->name();
+}
-</code>
+</syntaxhighlight>
 This code will look for a KPart that is both capable of reading/writing plain text files and is also a KOffice component, or can simply read ODF document formats.
@@ Line 123: / Line 123: @@
 An identifier can be checked for existence with the '''exist''' operator, e.g. "exist [X-KDE-Library]". This is especially useful when checking for the value of an identifier with a default value. For example, if MyProp is a property with type boolean, one might write "not exist MyProp or MyProp" to match MyProp with a default of "true".
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 QString term = "konq";
 QString query = QString("exist Exec and ((exist Keywords and '%1' ~subin Keywords) or (exist GenericName and '%1' ~~ GenericName) or (exist Name and '%1' ~~ Name))").arg(term);
@@ Line 130: / Line 130: @@
      kDebug() << service->name();
+}
-</code>
+</syntaxhighlight>
 === Comparison Operators ===
@@ Line 184: / Line 184: @@
 == Command line tool ==
-* ktraderclient --mimetype <var >mimetype</var > --servicetype <var >servicetype</var > --constraint <var >constraint</var >
+<pre>

← Older revision		Revision as of 10:39, 30 November 2010
Line 182:		Line 182:
	* '''subin''': the list contains the string as a substring of one of the entries, e.g. "'Plugin' subin ServiceTypes'"		* '''subin''': the list contains the string as a substring of one of the entries, e.g. "'Plugin' subin ServiceTypes'"
	* '''~subin''': the list contains the string as a substring of one of the entries, with case insensitive matching		* '''~subin''': the list contains the string as a substring of one of the entries, with case insensitive matching
		+
		+	== Command line tool ==
		+	* ktraderclient --mimetype <var >mimetype</var > --servicetype <var >servicetype</var > --constraint <var >constraint</var >

← Older revision		Revision as of 03:08, 10 December 2008
Line 122:		Line 122:

	An identifier can be checked for existence with the '''exist''' operator, e.g. "exist [X-KDE-Library]". This is especially useful when checking for the value of an identifier with a default value. For example, if MyProp is a property with type boolean, one might write "not exist MyProp or MyProp" to match MyProp with a default of "true".		An identifier can be checked for existence with the '''exist''' operator, e.g. "exist [X-KDE-Library]". This is especially useful when checking for the value of an identifier with a default value. For example, if MyProp is a property with type boolean, one might write "not exist MyProp or MyProp" to match MyProp with a default of "true".
		+
		+	<code cppqt>
		+	QString term = "konq";
		+	QString query = QString("exist Exec and ((exist Keywords and '%1' ~subin Keywords) or (exist GenericName and '%1' ~~ GenericName) or (exist Name and '%1' ~~ Name))").arg(term);
		+	KService::List services = KServiceTypeTrader::self()->query("Application", query);
		+	foreach (KService::Ptr service, services) {
		+	kDebug() << service->name();
		+	}
		+	</code>

	=== Comparison Operators ===		=== Comparison Operators ===

@@ Line 167: / Line 167: @@
 * '''~~''': contains with case insensitive matching, e.g. "'Bar' ~~ 'FoobarBaz'" is true
-Some properties, such as MimeTypes and ServiceTypes, are lists of strings. These lists can be searched using the following two operators:
+Some properties, such as MimeTypes and ServiceTypes, are lists of strings. These lists can be searched using the following operators:
 * '''in''': the list contains the string, e.g. "'MyApp/Plugin' in ServiceTypes'"
 * '''~in''': the list contains the string, with case insensitive matching

@@ Line 45: / Line 45: @@
 The service trader is always accessed via the <tt>self()</tt> singleton accessor. With the {{class|KServiceTypeTrader}} in hand, we can then do one of three things:
-*'''query''':query for a list of services ordered according to the user's preferences (if any)
+*'''query''': query for a list of services ordered according to the user's preferences (if any)
 *'''defaultOffers''': request all services, unsorted
 *'''preferredService''': request the preferred service of a given type

← Older revision		Revision as of 15:02, 20 November 2007
Line 1:		Line 1:
		+	{{Template:I18n/Language Navigation Bar\|Development/Tutorials/Services/Traders}}
		+
	{{TutorialBrowser\|		{{TutorialBrowser\|

@@ Line 72: / Line 72: @@
 == The KTrader Query Language ==
-The above examples are quite simplistic and are not detailed enough for many application needs. For instance, one may want to list only plugins with a certain category, that are associated with a particular mimetype or that have a specific plugin name. This is where the query language comes in.
+The above examples are quite simplistic and are not detailed enough for many application needs. For instance, we may only want to list plugins for a certain category, that are associated with a particular mimetype, or that have a specific plugin name. This is where the query language comes in.
-The query language itself is designed to be human readable and flexible. <tt>{{class|KServiceTypeTrader}}::query</tt> optional takes a query in addition to the service type and uses that to provide more fine-grained searches. So example, we may modify the earlier example in this way:
+The query language itself is designed to be human readable and flexible. <tt>{{class|KServiceTypeTrader}}::query</tt> optionally takes a query, in addition to the service type, and uses that to provide more fine-grained searches. So, for example, we'll modify the earlier example in the following way:
 <code cppqt>
@@ Line 90: / Line 90: @@
 </code>
-This would look for a KPart capable of both reading and writing plain text files that is also a KOffice component or which can read ODF document formats.
+This code will look for a KPart that is both capable of reading/writing plain text files and is also a KOffice component, or can simply read ODF document formats.
 Errors in queries are reported via debug output to console at runtime.
@@ Line 96: / Line 96: @@
 === Order of Operations ===
-The query string is evaluated left to right one section at a time. Sections are divided by boolean operators (see below) or by parentheses ('()') which serve as grouping characters.
+The query string is evaluated left to right, one section at a time. Sections are divided by boolean operators (see below) or by parentheses ('()'), which serve as grouping characters.
 === Literals ===
@@ Line 108: / Line 108: @@
 === Identifiers ===
-Identifiers in query string are mapped to entries listed in the service's <tt>.desktop</tt> file. For example, "Name" is the name of the service, "ServiceTypes" is a list of the service types it supports.
+Identifiers in a query string are mapped to entries listed in the service's <tt>.desktop</tt> file. For example, "Name" is the name of the service, "ServiceTypes" is a list of the service types it supports.
-Identifiers may contain only alphanumeric characters and the '-' character.
+Identifiers may only contain alphanumeric characters and the '-' character.
-Identifiers that do not start with an alphabetical character or contain non-alphanumeric characters must be enclosed in brackets, e.g. [X-KDE-Init].
+Identifiers that do not start with an alphabetical character or that contain non-alphanumeric characters must be enclosed in brackets, e.g. [X-KDE-Init].
 There are also three special identifiers:
-*'''DesktopEntryName''' stands for the filename of the service desktop entry without any extension. This can be useful to exclude some specific services.
+*'''DesktopEntryName''' stands for the filename of the service desktop entry without its extension. This can be useful to exclude some specific services.
 *'''DesktopEntryPath''' stands for the relative or full path to the .desktop file, see {{class|KService}}::desktopEntryPath.
 *'''Library''': a synonym for [X-KDE-Library] in the .desktop file.
-An identifier can be checked for existence with the '''exist''' operator, e.g. "exist [X-KDE-Library]". This is especially useful when checking for the value of an identifier with a default value. For example, if MyProp is a property with type boolean one might write "not exist MyProp or MyProp" to match MyProp with a default of "true".
+An identifier can be checked for existence with the '''exist''' operator, e.g. "exist [X-KDE-Library]". This is especially useful when checking for the value of an identifier with a default value. For example, if MyProp is a property with type boolean, one might write "not exist MyProp or MyProp" to match MyProp with a default of "true".
 === Comparison Operators ===
-The following comparison operators may be used to compare values of any of the supported data types:
+The following comparison operators can be used to compare values of any of the supported data types:
 *'''==''': equality
@@ Line 151: / Line 151: @@
 === String Matching Operators ===
-The string matching operators all return a boolean value indicating success or failure.
+The string matching operators all return a boolean value, indicating success or failure.
-String comparisons are done using the following operators which:
+String comparisons are done using the following operators:
 *'''==''': equality, case sensitive
@@ Line 160: / Line 160: @@
 *'''!~''': inequality, case insensitive
-Sub-string matching can be accomplished using the following operators:
+Sub-string matching can be accomplished by using the following operators:
 * '''~''': contains, e.g. "'Bar' ~ 'FooBarBaz'" is true

@@ Line 22: / Line 22: @@
 == Service Types ==
-{{class|KServiceTypeTrader}} is used to locate individual components such as application plugins, screensavers and control panels that are registered with the system. The primary concept used is that of the "service type". Each set of services has a unique service type, which makes it very easy to locate exactly the sort of component needed.
+{{class|KServiceTypeTrader}} is used to locate individual components such as application plugins, screensavers, and control panels that are registered with the system. The primary concept used here, is that of the "service type". Each set of services has a unique service type, which makes it very easy to locate the sort of component needed.
-This means that each kind of application plugin is uniquely namespaced within the set of all services so it is trivial to locate plugins for a given application without having to worry about also getting another application's plugins in the list.
+This means that, each kind of application plugin is uniquely namespaced within the set of all services. So, it is trivial to locate plugins for a given application, without having to worry about getting another application's plugin in the list.
 Examples of service types include:
@@ Line 35: / Line 35: @@
 *KDevelop/Plugin
-There is no limit to the number of service types that a given application may use or register. Creating new service types is covered in the next tutorial in the series, [[Development/Tutorials/Services/Plugins|Creating and Loading Plugins Using KService]]. Of course, service types are not limited to plugins and may be used for any sort of data component.
+There is no limit to the number of service types that a given application may use or register. Of course, service types are not limited to plugins and may be used for any sort of data component.
 == Basic KServiceTypeTrader Usage ==