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AnjutaPlugin

AnjutaPlugin — Anjuta plugin base class from which all plugins are derived.

Stability Level

Unstable, unless otherwise indicated

Functions

void (*AnjutaPluginValueAdded) ()
void (*AnjutaPluginValueRemoved) ()
gboolean anjuta_plugin_activate ()
gboolean anjuta_plugin_deactivate ()
gboolean anjuta_plugin_is_active ()
guint anjuta_plugin_add_watch ()
void anjuta_plugin_remove_watch ()
AnjutaShell * anjuta_plugin_get_shell ()
#define ANJUTA_PLUGIN_BEGIN()
#define ANJUTA_PLUGIN_ADD_INTERFACE()
#define ANJUTA_PLUGIN_BOILERPLATE()

Properties

AnjutaShell * shell Read / Write / Construct

Signals

void activated Run First
void deactivated Run First

Types and Values

typedef AnjutaGluePlugin
#define ANJUTA_PLUGIN_END

Object Hierarchy

    GObject
    ╰── AnjutaPlugin

Includes

#include <libanjuta/anjuta-plugin.h>

Description

Anjuta plugins are components which are loaded in Anjuta IDE shell either on startup or on demand to perform various subtasks. Plugins are specialized in doing only a very specific task and can let other plugins interract with it using interfaces.

A plugin class is derived from AnjutaPlugin class and will be used by shell to instanciate any number of plugin objects.

When a plugin class is derived from AnjutaPlugin, the virtual mehtods activate and deactivate must be implemented. The activate method is used to activate the plugin. Note that plugin activation is different from plugin instance initialization. Instance initialization is use to do internal initialization, while activate method is used to setup the plugin in shell, UI and preferences. Other plugins can also be queried in activate method.

Following things should be done in activate method.

  1. Register UI Actions: Use anjuta_ui_add_action_group_entries() or anjuta_ui_add_toggle_action_group_entries() to add your action groups.

  2. Merge UI definition file: Use anjuta_ui_merge() to merge a UI file. See AnjutaUI for more detail.

  3. Add widgets to Anjuta Shell: If the plugin has one or more widgets as its User Interface, they can be added with anjuta_shell_add_widget().

  4. Setup value watches with anjuta_plugin_add_watch().

deactivate method undos all the above. That is, it removes widgets from the shell, unmerges UI and removes the action groups.

Plugins interact with each other using interfaces. A plugin can expose an interface which will let other plugins find it. Any number of interfaces can be exposed by a plugin. These exposed interfaces are called Primary interfaces of the plugin. The condition for the interfaces to be primary is that they should be independent (i.e. an external entity requesting to use a primary interface should not require other primary interfaces). For example, an editor plugin can implement IAnjutaEditor, IAnjutaStream and IAnjutaFile interfaces and expose them as primary interfaces, because they are independent. Primary interfaces exposed by a plugin are exported in its plugin meta-data file, so that plugin manager could register them.

Any other interfaces implemented by the plugin are called Secondary interfaces and they generally depend on one or more primary interfaces. For example, IAnjutaEditor is the primary interface of anjuta-editor plugin, but it also implements secondary interfaces IAnjutaEditorGutter and IAnjutaEditorBuffer. Notice that secondary interfaces IAnjutaEditorGutter and IAnjutaEditorBuffer depend on IAnjutaEditor interface.

The purpose of distinguishing between primary and secondary interfaces is only at plugin level. At code level, they behave just the same and there is no difference. So, a natural sequence for a plugin to communicate with another plugin is:

  1. Query the shell for a plugin implemeting the primary interface using anjuta_shell_get_interface(). It will return an implemetation of the interface (or NULL if not found). Do not save this object for longer use, because the implementor plugin can change anytime and a different plugin implementing the same primary interface may be activated. 

    GError *err = NULL;
IAnjutaDocumentManager *docman;
IAnjutaEditor *editor;

docman = anjuta_shell_get_interface (ANJUTA_PLUGIN(plugin)->shell,
                                     IAnjutaDocumentManager, &err);
if (err)
{
	g_warning ("Error encountered: %s", err->message);
	g_error_free (err);
	return;
}

editor = ianjuta_document_manager_get_current_editor (docman, &err);
if (err)
{
	g_warning ("Error encountered: %s", err->message);
	g_error_free (err);
	return;
}

ianjuta_editor_goto_line (editor, 200);
...

  2. A primary interface of a plugin can be directly used, but to use a secondary interface, make sure to check if the plugin object implements it. For example, to check if editor plugin implements IAnjutaEditorGutter interface, do something like: 

    if (IANJUTA_IS_EDITOR_GUTTER(editor))
{
	ianjuta_editor_gutter_set_marker(IANJUTA_EDITOR_GUTTER (editor),
	                                 ANJUTA_EDITOR_MARKER_1,
	                                 line_number, &err);
}

Plugins can also communicate with outside using Shell's Values System. Values are objects exported by plugins to make them available to other plugins. Read AnjutaShell documentation for more detail on Values System. A plugin can set up watches with anjuta_plugin_add_watch() to get notifications for values exported by other plugins.

Values are very unreliable way of passing objects between plugins, but are nevertheless very useful (and quicker to code). It must be used with care. As a rule of thumb, a plugin should only watch values of other trusted plugins. For example, a group of plugins forming a subsystem can comfortably use values to pass objects and notifications. Use anjuta_plugin_add_watch() and anjuta_plugin_remove_watch() to add or remove value watches.

Functions

AnjutaPluginValueAdded ()

void
(*AnjutaPluginValueAdded) (AnjutaPlugin *plugin,
                           const char *name,
                           const GValue *value,
                           gpointer user_data);

The callback to pass to anjuta_plugin_add_watch(). When a name value is added to shell by another plugin, this callback will be called.

Parameters

plugin

The AnjutaPlugin based plugin

  

name

name of value being added.

  

value

value of value being added.

  

user_data

User data set during anjuta_plugin_add_watch()

  

AnjutaPluginValueRemoved ()

void
(*AnjutaPluginValueRemoved) (AnjutaPlugin *plugin,
                             const char *name,
                             gpointer user_data);

The callback to pass to anjuta_plugin_add_watch(). When the name value is removed from the shell (by the plugin exporting this value), this callback will be called.

Parameters

plugin

The AnjutaPlugin based plugin

  

name

name of value being added.

  

user_data

User data set during anjuta_plugin_add_watch()

  

anjuta_plugin_activate ()

gboolean
anjuta_plugin_activate (AnjutaPlugin *plugin);

Activates the plugin by calling activate() virtual method. All plugins should derive their classes from this virtual class and implement this method. If the plugin implements IAnjutaPreferences, it is prompted to install it's preferences.

Parameters

plugin

a AnjutaPlugin derived class object.

  

Returns

TRUE if sucessfully activated, FALSE otherwise.

anjuta_plugin_deactivate ()

gboolean
anjuta_plugin_deactivate (AnjutaPlugin *plugin);

Deactivates the plugin by calling deactivate() virtual method. All plugins should derive their classes from this virtual class and implement this method.

Parameters

plugin

a AnjutaPlugin derived class object.

  

Returns

TRUE if sucessfully activated, FALSE otherwise.

anjuta_plugin_is_active ()

gboolean
anjuta_plugin_is_active (AnjutaPlugin *plugin);

Returns TRUE if the plugin has been activated.

Parameters

plugin

a AnjutaPlugin derived class object.

  

Returns

TRUE if activated, FALSE otherwise.

anjuta_plugin_add_watch ()

guint
anjuta_plugin_add_watch (AnjutaPlugin *plugin,
                         const gchar *name,
                         AnjutaPluginValueAdded added,
                         AnjutaPluginValueRemoved removed,
                         gpointer user_data);

Adds a watch for name value. When the value is added in shell, the added callback will be called and when it is removed, the removed callback will be called. The returned ID is used to remove the watch later.

Parameters

plugin

a AnjutaPlugin derived class object.

  

name

Name of the value to watch.

  

added

Callback to call when the value is added.

[closure user_data][scope call]

removed

Callback to call when the value is removed.

[closure user_data][scope call]

user_data

User data to pass to callbacks.

  

Returns

Watch ID.

anjuta_plugin_remove_watch ()

void
anjuta_plugin_remove_watch (AnjutaPlugin *plugin,
                            guint id,
                            gboolean send_remove);

Removes the watch represented by id (which was returned by anjuta_plugin_add_watch()).

Parameters

plugin

a AnjutaPlugin derived class object.

  

id

Watch id to remove.

  

send_remove

If true, calls value_removed callback.

  

anjuta_plugin_get_shell ()

AnjutaShell *
anjuta_plugin_get_shell (AnjutaPlugin *plugin);

Parameters

plugin

a AnjutaPlugin

  

Returns

The AnjutaShell object associated with this plugin.

[transfer none]

ANJUTA_PLUGIN_BEGIN()

#define             ANJUTA_PLUGIN_BEGIN(class_name, prefix)

This is a convienient macro defined to make it easy to write plugin classes . This macro begins the class type definition. member function prefix _class_init and prefix _instance_init should be statically defined before using this macro.

The class type definition is finished with ANJUTA_PLUGIN_END() macro. In between which any number of interface definitions could be added with ANJUTA_PLUGIN_ADD_INTERFACE() macro.

Parameters

class_name

Name of the class. e.g. EditorPlugin

  

prefix

prefix of member function names. e.g. editor_plugin

  

ANJUTA_PLUGIN_ADD_INTERFACE()

#define             ANJUTA_PLUGIN_ADD_INTERFACE(prefix,interface_type)

This is a convienient macro defined to make it easy to add interfaces to a plugin type. prefix _iface_init should be statically defined before using this macro. This macro should be called between ANJUTA_PLUGIN_BEGIN() and ANJUTA_PLUGIN_END() macros.

Parameters

prefix

prefix of member function names.

  

interface_type

Interface type. e.g. IANJUTA_TYPE_EDITOR

  

ANJUTA_PLUGIN_BOILERPLATE()

#define             ANJUTA_PLUGIN_BOILERPLATE(class_name, prefix)

This macro is similar to using ANJUTA_PLUGIN_BEGIN() and then immediately using ANJUTA_PLUGIN_END(). It is basically a plugin type definition macro that does not have any interface implementation.

Parameters

class_name

Name of the class. e.g EditorPlugin

  

prefix

prefix of member function names. e.g. editor_plugin

  

Types and Values

AnjutaGluePlugin

typedef GTypeModule AnjutaGluePlugin;

ANJUTA_PLUGIN_END

#define             ANJUTA_PLUGIN_END

Ends the plugin class type definition started with ANJUTA_PLUGIN_BEGIN()

Property Details

The “shell” property

  “shell”                    AnjutaShell *

Anjuta shell that will contain the plugin.

Flags: Read / Write / Construct

Signal Details

The “activated” signal

void
user_function (AnjutaPlugin *anjutaplugin,
               gpointer      user_data)

Flags: Run First

The “deactivated” signal

void
user_function (AnjutaPlugin *anjutaplugin,
               gpointer      user_data)

Flags: Run First

See Also

AnjutaPluginManager, AnjutaProfileManager

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