Development/Tutorials/Services/Plugins - Revision history

AnneW at 09:16, 14 July 2012

2012-07-14T09:16:46Z

Aseigo: /* The plugin loading stuff */

2011-11-15T10:46:12Z

‎The plugin loading stuff

Icwiener: Fix syntax highlighting.

2011-06-27T15:34:04Z

Fix syntax highlighting.

Ramblurr: /* Handling plugins by the Main Application */ fix typo

2010-02-06T15:44:12Z

‎Handling plugins by the Main Application: fix typo

Tampakrap: fixing memory leak

2009-11-14T08:43:04Z

fixing memory leak

Comawhite: Should've been getting the interface because it was overriding the existing KTextEdit and resulting in a constant null pointer

2009-04-20T03:05:42Z

Should've been getting the interface because it was overriding the existing KTextEdit and resulting in a constant null pointer

Alediaferia at 15:57, 27 February 2009

2009-02-27T15:57:00Z

Alediaferia at 15:52, 27 February 2009

2009-02-27T15:52:50Z

Tampakrap: typo

2009-02-27T13:16:03Z

typo

Alediaferia at 11:19, 23 December 2008

2008-12-23T11:19:27Z

← Older revision		Revision as of 09:16, 14 July 2012
Line 1:		Line 1:
−	~~{{Template:I18n/Language Navigation Bar\|Development/Tutorials/Services/Plugins}}~~	+

	{{TutorialBrowser\|		{{TutorialBrowser\|

@@ Line 116: / Line 116: @@
 This macro simply unifies two KDE macros that allow us the exportation of the plugin.
-== The plugin loading stuff ==
+== Loading Plugins ==
 Now let's get prepared to make our application find and load every compatible plugin. We'll make use of a simple helper that uses standard KDE methods in order to locate and load plugins. Here follows header and implementation

@@ Line 24: / Line 24: @@
 This class will be inherited by every plugin and should give access to the key resources of the main application. In this example the main plugin class will inherit a KXMLGUIClient since every plugin will give access to its features through a gui element (a KAction in this case).
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 #include <kdemacros.h>
 #include <kxmlguiclient.h>
@@ Line 55: / Line 55: @@
 };
-</code>
+</syntaxhighlight>
 This base class will give the useful pointers needed by each plugin in order to manipulate the main application data. In this case we only give access to the main editor interface through editorInterface().
@@ Line 61: / Line 61: @@
 Here follows the implementation:
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 #include "plugin.h"
 #include <KTextEdit>
@@ Line 95: / Line 95: @@
+}
-</code>
+</syntaxhighlight>
 Where plugin.h is the header file seen before.
@@ Line 104: / Line 104: @@
 So we better put this macro in our own myplugin_macros.h as follows.
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 #include <kdemacros.h>
 #include <KPluginFactory>
@@ Line 112: / Line 112: @@
    K_PLUGIN_FACTORY( TextEditorFactory, registerPlugin< c >(); ) \
    K_EXPORT_PLUGIN( TextEditorFactory("c") )
-</code>
+</syntaxhighlight>
 This macro simply unifies two KDE macros that allow us the exportation of the plugin.
@@ Line 119: / Line 119: @@
 Now let's get prepared to make our application find and load every compatible plugin. We'll make use of a simple helper that uses standard KDE methods in order to locate and load plugins. Here follows header and implementation
-PLUGINLOADER.H
+=== PLUGINLOADER.H ===
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 #include <QObject>
@@ Line 140: / Line 140: @@
          void pluginLoaded(Plugin * plugin);
 };
-</code>
+</syntaxhighlight>
-PLUGINLOADER.CPP
+=== PLUGINLOADER.CPP ===
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 #include "pluginloader.h"
@@ Line 176: / Line 176: @@
          if (!factory)
+         {
-             //KMessageBox::error(0, i18n("<html><p>KPluginFactory could not load the plugin:<br/><i>%1</i></p></html>",
+             //KMessageBox::error(0, i18n("<html><p>KPluginFactory could not load the plugin:<br /><i>%1</i></p></html>",
                //                         service->library()));
              kError(5001) << "KPluginFactory could not load the plugin:" << service->library();
@@ Line 192: / Line 192: @@
+     }
+}
-</code>
+</syntaxhighlight>
 The code shown simply queries SyCoCa for a plugin for the TextEditor. When creating a plugin a .desktop file is provided with the Service Type the plugin is designed for. We'll see later how to set the proper Service Type for our custom plugin. We emit the pluginLoaded signal when the plugin is properly loaded so that the application will integrate it in the GUI.
@@ Line 200: / Line 200: @@
 Let's assume we have a pointer to our KTextEdit simply called editor.
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 void MyMainWindow::loadPlugins()
+{
@@ Line 207: / Line 207: @@
      loader->loadAllPlugins();
+}
-</code>
+</syntaxhighlight>
 So with this piece of code we ask PluginLoader to load all plugins and call the slot pluginLoaded we'll see now to implement the plugins in the interface.
 The loadPlugins method is supposed to be called at the beginning of the application in order to load everything before the user can start using it. Of course you can decide what to do with your plugins and ignore this suggestion :).
-<code cppqt>
+<syntaxhighlight lang="cpp-qt">
 void MyMainWindow::addPlugin(Plugin *plugin)
+{
@@ Line 218: / Line 218: @@
      guiFactory()->addClient(plugin);
+}
-</code>
+</syntaxhighlight>
 Since our plugin inherits KXMLGuiClient we can provide any kind of gui client supported and KDE will automagically load it into our application. So this code snippet simply integrates our plugin with the main window.
 == A Simple Plugin Example ==

@@ Line 205: / Line 205: @@
      PluginLoader *loader = new PluginLoader(this);
      connect(loader, SIGNAL(pluginLoaded(Plugin*)), this, SLOT(addPlugin(Plugin*)));
-     pluginLoader->loadAllPlugins();
+     loader->loadAllPlugins();
+}
 </code>

@@ Line 81: / Line 81: @@
 Plugin::~Plugin()
 {}
 KTextEdit* Plugin::editorInterface()

@@ Line 213: / Line 213: @@
 void MyMainWindow::addPlugin(Plugin *plugin)
+{
-     plugin->setEditorInterface(editor);
+     editor = plugin->editorInterface();
      guiFactory()->addClient(plugin);
+}

@@ Line 217: / Line 217: @@
+}
 </code>
-== Registering a Plugin With the SyCoCa ==
+Since our plugin inherits KXMLGuiClient we can provide any kind of gui client supported and KDE will automagically load it into our application. So this code snippet simply integrates our plugin with the main window.
-== Finding Plugins ==
+== A Simple Plugin Example ==
-−
-== Instantiating Plugins ==

@@ Line 58: / Line 58: @@
 This base class will give the useful pointers needed by each plugin in order to manipulate the main application data. In this case we only give access to the main editor interface through editorInterface().
 == The Plugin Factory Macro ==
@@ Line 73: / Line 112: @@
 </code>
-== Registering a Plugin Type ==
+This macro simply unifies two KDE macros that allow us the exportation of the plugin.
 == Registering a Plugin With the SyCoCa ==

@@ Line 22: / Line 22: @@
 == Creating a Plugin Interface Class ==
 The main step in order to create a plugin structure is to define its base class.
-This class will be inherited by every plugin and shuld give access to the key resources of the main application. In this example the main plugin class will inherit a KXMLGUIClient since every plugin will give access to its features through a gui element (a KAction in this case).
+This class will be inherited by every plugin and should give access to the key resources of the main application. In this example the main plugin class will inherit a KXMLGUIClient since every plugin will give access to its features through a gui element (a KAction in this case).
 <code cppqt>