class Gio::Application
- Gio::Application
- GObject::Object
- Reference
- Object
Overview
A #GApplication is the foundation of an application. It wraps some low-level platform-specific services and is intended to act as the foundation for higher-level application classes such as #Gtk::Application or #MxApplication. In general, you should not use this class outside of a higher level framework.
GApplication provides convenient life cycle management by maintaining a "use count" for the primary application instance. The use count can be changed using g_application_hold() and g_application_release(). If it drops to zero, the application exits. Higher-level classes such as #Gtk::Application employ the use count to ensure that the application stays alive as long as it has any opened windows.
Another feature that GApplication (optionally) provides is process uniqueness. Applications can make use of this functionality by providing a unique application ID. If given, only one application with this ID can be running at a time per session. The session concept is platform-dependent, but corresponds roughly to a graphical desktop login. When your application is launched again, its arguments are passed through platform communication to the already running program. The already running instance of the program is called the "primary instance"; for non-unique applications this is always the current instance. On Linux, the D-Bus session bus is used for communication.
The use of #GApplication differs from some other commonly-used uniqueness libraries (such as libunique) in important ways. The application is not expected to manually register itself and check if it is the primary instance. Instead, the main() function of a #GApplication should do very little more than instantiating the application instance, possibly connecting signal handlers, then calling g_application_run(). All checks for uniqueness are done internally. If the application is the primary instance then the startup signal is emitted and the mainloop runs. If the application is not the primary instance then a signal is sent to the primary instance and g_application_run() promptly returns. See the code examples below.
If used, the expected form of an application identifier is the same as
that of of a
D-Bus well-known bus name.
Examples include: com.example.MyApp
, org.example.internal_apps.Calculator
,
org._7_zip.Archiver
.
For details on valid application identifiers, see g_application_id_is_valid().
On Linux, the application identifier is claimed as a well-known bus name on the user's session bus. This means that the uniqueness of your application is scoped to the current session. It also means that your application may provide additional services (through registration of other object paths) at that bus name. The registration of these object paths should be done with the shared GDBus session bus. Note that due to the internal architecture of GDBus, method calls can be dispatched at any time (even if a main loop is not running). For this reason, you must ensure that any object paths that you wish to register are registered before #GApplication attempts to acquire the bus name of your application (which happens in g_application_register()). Unfortunately, this means that you cannot use g_application_get_is_remote() to decide if you want to register object paths.
GApplication also implements the #GActionGroup and #GActionMap interfaces and lets you easily export actions by adding them with g_action_map_add_action(). When invoking an action by calling g_action_group_activate_action() on the application, it is always invoked in the primary instance. The actions are also exported on the session bus, and GIO provides the #GDBusActionGroup wrapper to conveniently access them remotely. GIO provides a #GDBusMenuModel wrapper for remote access to exported #GMenuModels.
There is a number of different entry points into a GApplication:
-
via 'Activate' (i.e. just starting the application)
-
via 'Open' (i.e. opening some files)
-
by handling a command-line
-
via activating an action
The #GApplication::startup signal lets you handle the application initialization for all of these in a single place.
Regardless of which of these entry points is used to start the application, GApplication passes some ‘platform data’ from the launching instance to the primary instance, in the form of a #GVariant dictionary mapping strings to variants. To use platform data, override the before_emit or after_emit virtual functions in your #GApplication subclass. When dealing with #GApplicationCommandLine objects, the platform data is directly available via g_application_command_line_get_cwd(), g_application_command_line_get_environ() and g_application_command_line_get_platform_data().
As the name indicates, the platform data may vary depending on the operating system, but it always includes the current directory (key "cwd"), and optionally the environment (ie the set of environment variables and their values) of the calling process (key "environ"). The environment is only added to the platform data if the %G_APPLICATION_SEND_ENVIRONMENT flag is set. #GApplication subclasses can add their own platform data by overriding the add_platform_data virtual function. For instance, #Gtk::Application adds startup notification data in this way.
To parse commandline arguments you may handle the #GApplication::command-line signal or override the local_command_line() vfunc, to parse them in either the primary instance or the local instance, respectively.
For an example of opening files with a GApplication, see gapplication-example-open.c.
For an example of using actions with GApplication, see gapplication-example-actions.c.
For an example of using extra D-Bus hooks with GApplication, see gapplication-example-dbushooks.c.
Included Modules
Direct Known Subclasses
Defined in:
lib/gi-crystal/src/auto/gio-2.0/application.crlib/gi-crystal/src/bindings/gio/application.cr
Constructors
-
.new(application_id : String | Nil, flags : Gio::ApplicationFlags) : self
Creates a new #GApplication instance.
-
.new
Initialize a new
Application
. - .new(*, action_group : Gio::ActionGroup | Nil = nil, application_id : String | Nil = nil, flags : Gio::ApplicationFlags | Nil = nil, inactivity_timeout : UInt32 | Nil = nil, is_busy : Bool | Nil = nil, is_registered : Bool | Nil = nil, is_remote : Bool | Nil = nil, resource_base_path : String | Nil = nil)
Class Method Summary
-
.default : Gio::Application | Nil
Returns the default #GApplication instance for this process.
-
.g_type : UInt64
Returns the type id (GType) registered in GLib type system.
-
.id_is_valid(application_id : String) : Bool
Checks if application_id is a valid application identifier.
Instance Method Summary
-
#==(other : self)
Returns
true
if this reference is the same as other. -
#action_group=(action_group : Gio::ActionGroup | Nil) : Nil
This used to be how actions were associated with a #GApplication.
DEPRECATED
-
#activate : Nil
Activates the application.
- #activate_signal
-
#add_main_option(long_name : String, short_name : Int8, flags : GLib::OptionFlags, arg : GLib::OptionArg, description : String, arg_description : String | Nil) : Nil
Add an option to be handled by application.
-
#add_main_option_entries(entries : Enumerable(GLib::OptionEntry)) : Nil
Adds main option entries to be handled by application.
- #add_main_option_entries(*entries : GLib::OptionEntry)
-
#add_option_group(group : GLib::OptionGroup) : Nil
Adds a #GOptionGroup to the commandline handling of application.
-
#application_id : String | Nil
Gets the unique identifier for application.
- #application_id=(value : String) : String
-
#application_id=(value : Nil) : Nil
Set
#application_id
property to nil. -
#application_id=(application_id : String | Nil) : Nil
Sets the unique identifier for application.
-
#application_id? : String | Nil
Same as
#application_id
, but can return nil. -
#bind_busy_property(object : GObject::Object, property : String) : Nil
Marks application as busy (see g_application_mark_busy()) while property on object is
true
. - #command_line_signal
-
#dbus_connection : Gio::DBusConnection | Nil
Gets the #GDBusConnection being used by the application, or
nil
. -
#dbus_object_path : String | Nil
Gets the D-Bus object path being used by the application, or
nil
. -
#flags : Gio::ApplicationFlags
Gets the flags for application.
-
#flags=(flags : Gio::ApplicationFlags) : Nil
Sets the flags for application.
- #handle_local_options_signal
-
#hash(hasher)
See
Object#hash(hasher)
-
#hold : Nil
Increases the use count of application.
-
#inactivity_timeout : UInt32
Gets the current inactivity timeout for the application.
-
#inactivity_timeout=(inactivity_timeout : UInt32) : Nil
Sets the current inactivity timeout for the application.
-
#is_busy : Bool
Gets the application's current busy state, as set through g_application_mark_busy() or g_application_bind_busy_property().
- #is_busy? : Bool
-
#is_registered : Bool
Checks if application is registered.
- #is_registered? : Bool
-
#is_remote : Bool
Checks if application is remote.
- #is_remote? : Bool
-
#mark_busy : Nil
Increases the busy count of application.
- #name_lost_signal
-
#open(files : Enumerable(Gio::File), hint : String) : Nil
Opens the given files.
- #open_signal
-
#option_context_description=(description : String | Nil) : Nil
Adds a description to the application option context.
-
#option_context_parameter_string=(parameter_string : String | Nil) : Nil
Sets the parameter string to be used by the commandline handling of application.
-
#option_context_summary=(summary : String | Nil) : Nil
Adds a summary to the application option context.
-
#quit : Nil
Immediately quits the application.
-
#register(cancellable : Gio::Cancellable | Nil) : Bool
Attempts registration of the application.
-
#release : Nil
Decrease the use count of application.
-
#resource_base_path : String | Nil
Gets the resource base path of application.
- #resource_base_path=(value : String) : String
-
#resource_base_path=(value : Nil) : Nil
Set
#resource_base_path
property to nil. -
#resource_base_path=(resource_path : String | Nil) : Nil
Sets (or unsets) the base resource path of application.
-
#resource_base_path? : String | Nil
Same as
#resource_base_path
, but can return nil. -
#run(argv : Enumerable(String) | Nil) : Int32
Runs the application.
- #run(argv : Enumerable(String) | Nil) : Int32
-
#run : Int32
Invoke
Application#run
with the process argc/argv. - #run(*argv : String)
-
#send_notification(id : String | Nil, notification : Gio::Notification) : Nil
Sends a notification on behalf of application to the desktop shell.
-
#set_default : Nil
Sets or unsets the default application for the process, as returned by g_application_get_default().
- #shutdown_signal
- #startup_signal
-
#unbind_busy_property(object : GObject::Object, property : String) : Nil
Destroys a binding between property and the busy state of application that was previously created with g_application_bind_busy_property().
-
#unmark_busy : Nil
Decreases the busy count of application.
-
#withdraw_notification(id : String) : Nil
Withdraws a notification that was sent with g_application_send_notification().
Instance methods inherited from module Gio::ActionMap
add_action(action : Gio::Action) : Nil
add_action,
add_action_entries(entries : Enumerable(Gio::ActionEntry), user_data : Pointer(Void) | Nil) : Nil
add_action_entries,
lookup_action(action_name : String) : Gio::Action | Nil
lookup_action,
remove_action(action_name : String) : Nil
remove_action,
to_unsafe
to_unsafe
Constructor methods inherited from module Gio::ActionMap
cast(obj : GObject::Object) : self
cast
Class methods inherited from module Gio::ActionMap
cast?(obj : GObject::Object) : self | Nil
cast?,
g_type : UInt64
g_type
Instance methods inherited from module Gio::ActionGroup
action_added(action_name : String) : Nil
action_added,
action_added_signal
action_added_signal,
action_enabled(action_name : String) : Bool
action_enabled,
action_enabled_changed(action_name : String, enabled : Bool) : Nil
action_enabled_changed,
action_enabled_changed_signal
action_enabled_changed_signal,
action_parameter_type(action_name : String) : GLib::VariantType | Nil
action_parameter_type,
action_removed(action_name : String) : Nil
action_removed,
action_removed_signal
action_removed_signal,
action_state(action_name : String) : GLib::Variant | Nil
action_state,
action_state_changed(action_name : String, state : _) : Nil
action_state_changed,
action_state_changed_signal
action_state_changed_signal,
action_state_hint(action_name : String) : GLib::Variant | Nil
action_state_hint,
action_state_type(action_name : String) : GLib::VariantType | Nil
action_state_type,
activate_action(action_name : String, parameter : _ | Nil) : Nil
activate_action,
change_action_state(action_name : String, value : _) : Nil
change_action_state,
has_action(action_name : String) : Bool
has_action,
list_actions : Enumerable(String)
list_actions,
query_action(action_name : String, enabled : Bool) : Bool
query_action,
to_unsafe
to_unsafe
Constructor methods inherited from module Gio::ActionGroup
cast(obj : GObject::Object) : self
cast
Class methods inherited from module Gio::ActionGroup
cast?(obj : GObject::Object) : self | Nil
cast?,
g_type : UInt64
g_type
Instance methods inherited from class GObject::Object
==(other : self)
==,
bind_property(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags) : GObject::Binding
bind_property,
bind_property_full(source_property : String, target : GObject::Object, target_property : String, flags : GObject::BindingFlags, transform_to : GObject::Closure, transform_from : GObject::Closure) : GObject::Binding
bind_property_full,
data(key : String) : Pointer(Void) | Nil
data,
finalize
finalize,
freeze_notify : Nil
freeze_notify,
getv(names : Enumerable(String), values : Enumerable(_)) : Nil
getv,
hash(hasher)
hash,
notify(property_name : String) : Nil
notify,
notify_by_pspec(pspec : GObject::ParamSpec) : Nil
notify_by_pspec,
notify_signal
notify_signal,
property(property_name : String, value : _) : Nil
property,
qdata(quark : UInt32) : Pointer(Void) | Nil
qdata,
ref_count : UInt32
ref_count,
run_dispose : Nil
run_dispose,
set_data(key : String, data : Pointer(Void) | Nil) : Nil
set_data,
set_property(property_name : String, value : _) : Nil
set_property,
steal_data(key : String) : Pointer(Void) | Nil
steal_data,
steal_qdata(quark : UInt32) : Pointer(Void) | Nil
steal_qdata,
thaw_notify : Nil
thaw_notify,
to_unsafe : Pointer(Void)
to_unsafe,
watch_closure(closure : GObject::Closure) : Nil
watch_closure
Constructor methods inherited from class GObject::Object
cast(obj : GObject::Object) : self
cast,
new(pointer : Pointer(Void), transfer : GICrystal::Transfer)new new, newv(object_type : UInt64, parameters : Enumerable(GObject::Parameter)) : self newv
Class methods inherited from class GObject::Object
cast?(obj : GObject::Object) : self | Nil
cast?,
compat_control(what : UInt64, data : Pointer(Void) | Nil) : UInt64
compat_control,
g_type : UInt64
g_type,
interface_find_property(g_iface : GObject::TypeInterface, property_name : String) : GObject::ParamSpec
interface_find_property,
interface_list_properties(g_iface : GObject::TypeInterface) : Enumerable(GObject::ParamSpec)
interface_list_properties
Macros inherited from class GObject::Object
previous_vfunc(*args)
previous_vfunc,
previous_vfunc!(*args)
previous_vfunc!,
signal(signature)
signal
Constructor Detail
Creates a new #GApplication instance.
If non-nil
, the application id must be valid. See
g_application_id_is_valid().
If no application ID is given then some features of #GApplication (most notably application uniqueness) will be disabled.
Class Method Detail
Returns the default #GApplication instance for this process.
Normally there is only one #GApplication per process and it becomes the default when it is created. You can exercise more control over this by using g_application_set_default().
If there is no default application then nil
is returned.
Returns the type id (GType) registered in GLib type system.
Checks if application_id is a valid application identifier.
A valid ID is required for calls to g_application_new() and g_application_set_application_id().
Application identifiers follow the same format as D-Bus well-known bus names. For convenience, the restrictions on application identifiers are reproduced here:
-
Application identifiers are composed of 1 or more elements separated by a period (
.
) character. All elements must contain at least one character. -
Each element must only contain the ASCII characters
[A-Z][a-z][0-9]_-
, with-
discouraged in new application identifiers. Each element must not begin with a digit. -
Application identifiers must contain at least one
.
(period) character (and thus at least two elements). -
Application identifiers must not begin with a
.
(period) character. -
Application identifiers must not exceed 255 characters.
Note that the hyphen (-
) character is allowed in application identifiers,
but is problematic or not allowed in various specifications and APIs that
refer to D-Bus, such as
Flatpak application IDs,
the
DBusActivatable
interface in the Desktop Entry Specification,
and the convention that an application's "main" interface and object path
resemble its application identifier and bus name. To avoid situations that
require special-case handling, it is recommended that new application
identifiers consistently replace hyphens with underscores.
Like D-Bus interface names, application identifiers should start with the reversed DNS domain name of the author of the interface (in lower-case), and it is conventional for the rest of the application identifier to consist of words run together, with initial capital letters.
As with D-Bus interface names, if the author's DNS domain name contains
hyphen/minus characters they should be replaced by underscores, and if it
contains leading digits they should be escaped by prepending an underscore.
For example, if the owner of 7-zip.org used an application identifier for an
archiving application, it might be named org._7_zip.Archiver
.
Instance Method Detail
Returns true
if this reference is the same as other. Invokes same?
.
This used to be how actions were associated with a #GApplication. Now there is #GActionMap for that.
DEPRECATED
Activates the application.
In essence, this results in the #GApplication::activate signal being emitted in the primary instance.
The application must be registered before calling this function.
Add an option to be handled by application.
Calling this function is the equivalent of calling
g_application_add_main_option_entries() with a single #GOptionEntry
that has its arg_data member set to nil
.
The parsed arguments will be packed into a #GVariantDict which is passed to #GApplication::handle-local-options. If %G_APPLICATION_HANDLES_COMMAND_LINE is set, then it will also be sent to the primary instance. See g_application_add_main_option_entries() for more details.
See #GOptionEntry for more documentation of the arguments.
Adds main option entries to be handled by application.
This function is comparable to g_option_context_add_main_entries().
After the commandline arguments are parsed, the #GApplication::handle-local-options signal will be emitted. At this point, the application can inspect the values pointed to by arg_data in the given #GOptionEntrys.
Unlike #GOptionContext, #GApplication supports giving a nil
arg_data for a non-callback #GOptionEntry. This results in the
argument in question being packed into a #GVariantDict which is also
passed to #GApplication::handle-local-options, where it can be
inspected and modified. If %G_APPLICATION_HANDLES_COMMAND_LINE is
set, then the resulting dictionary is sent to the primary instance,
where g_application_command_line_get_options_dict() will return it.
This "packing" is done according to the type of the argument --
booleans for normal flags, strings for strings, bytestrings for
filenames, etc. The packing only occurs if the flag is given (ie: we
do not pack a "false" #GVariant in the case that a flag is missing).
In general, it is recommended that all commandline arguments are parsed locally. The options dictionary should then be used to transmit the result of the parsing to the primary instance, where g_variant_dict_lookup() can be used. For local options, it is possible to either use arg_data in the usual way, or to consult (and potentially remove) the option from the options dictionary.
This function is new in GLib 2.40. Before then, the only real choice was to send all of the commandline arguments (options and all) to the primary instance for handling. #GApplication ignored them completely on the local side. Calling this function "opts in" to the new behaviour, and in particular, means that unrecognised options will be treated as errors. Unrecognised options have never been ignored when %G_APPLICATION_HANDLES_COMMAND_LINE is unset.
If #GApplication::handle-local-options needs to see the list of
filenames, then the use of %G_OPTION_REMAINING is recommended. If arg_data is nil
then %G_OPTION_REMAINING can be used as a key into
the options dictionary. If you do use %G_OPTION_REMAINING then you
need to handle these arguments for yourself because once they are
consumed, they will no longer be visible to the default handling
(which treats them as filenames to be opened).
It is important to use the proper GVariant format when retrieving the options with g_variant_dict_lookup():
- for %G_OPTION_ARG_NONE, use
b
- for %G_OPTION_ARG_STRING, use
&s
- for %G_OPTION_ARG_INT, use
i
- for %G_OPTION_ARG_INT64, use
x
- for %G_OPTION_ARG_DOUBLE, use
d
- for %G_OPTION_ARG_FILENAME, use
^&ay
- for %G_OPTION_ARG_STRING_ARRAY, use
^a&s
- for %G_OPTION_ARG_FILENAME_ARRAY, use
^a&ay
Adds a #GOptionGroup to the commandline handling of application.
This function is comparable to g_option_context_add_group().
Unlike g_application_add_main_option_entries(), this function does
not deal with nil
arg_data and never transmits options to the
primary instance.
The reason for that is because, by the time the options arrive at the primary instance, it is typically too late to do anything with them. Taking the GTK option group as an example: GTK will already have been initialised by the time the #GApplication::command-line handler runs. In the case that this is not the first-running instance of the application, the existing instance may already have been running for a very long time.
This means that the options from #GOptionGroup are only really usable
in the case that the instance of the application being run is the
first instance. Passing options like --display=
or --gdk-debug=
on future runs will have no effect on the existing primary instance.
Calling this function will cause the options in the supplied option group to be parsed, but it does not cause you to be "opted in" to the new functionality whereby unrecognised options are rejected even if %G_APPLICATION_HANDLES_COMMAND_LINE was given.
Sets the unique identifier for application.
The application id can only be modified if application has not yet been registered.
If non-nil
, the application id must be valid. See
g_application_id_is_valid().
Marks application as busy (see g_application_mark_busy()) while property on object is true
.
The binding holds a reference to application while it is active, but not to object. Instead, the binding is destroyed when object is finalized.
Gets the #GDBusConnection being used by the application, or nil
.
If #GApplication is using its D-Bus backend then this function will return the #GDBusConnection being used for uniqueness and communication with the desktop environment and other instances of the application.
If #GApplication is not using D-Bus then this function will return
nil
. This includes the situation where the D-Bus backend would
normally be in use but we were unable to connect to the bus.
This function must not be called before the application has been registered. See g_application_get_is_registered().
Gets the D-Bus object path being used by the application, or nil
.
If #GApplication is using its D-Bus backend then this function will return the D-Bus object path that #GApplication is using. If the application is the primary instance then there is an object published at this path. If the application is not the primary instance then the result of this function is undefined.
If #GApplication is not using D-Bus then this function will return
nil
. This includes the situation where the D-Bus backend would
normally be in use but we were unable to connect to the bus.
This function must not be called before the application has been registered. See g_application_get_is_registered().
Sets the flags for application.
The flags can only be modified if application has not yet been registered.
See #GApplicationFlags.
Increases the use count of application.
Use this function to indicate that the application has a reason to continue to run. For example, g_application_hold() is called by GTK+ when a toplevel window is on the screen.
To cancel the hold, call g_application_release().
Gets the current inactivity timeout for the application.
This is the amount of time (in milliseconds) after the last call to g_application_release() before the application stops running.
Sets the current inactivity timeout for the application.
This is the amount of time (in milliseconds) after the last call to g_application_release() before the application stops running.
This call has no side effects of its own. The value set here is only used for next time g_application_release() drops the use count to zero. Any timeouts currently in progress are not impacted.
Gets the application's current busy state, as set through g_application_mark_busy() or g_application_bind_busy_property().
Checks if application is registered.
An application is registered if g_application_register() has been successfully called.
Checks if application is remote.
If application is remote then it means that another instance of application already exists (the 'primary' instance). Calls to perform actions on application will result in the actions being performed by the primary instance.
The value of this property cannot be accessed before g_application_register() has been called. See g_application_get_is_registered().
Increases the busy count of application.
Use this function to indicate that the application is busy, for instance while a long running operation is pending.
The busy state will be exposed to other processes, so a session shell will use that information to indicate the state to the user (e.g. with a spinner).
To cancel the busy indication, use g_application_unmark_busy().
The application must be registered before calling this function.
Opens the given files.
In essence, this results in the #GApplication::open signal being emitted in the primary instance. n_files must be greater than zero. hint is simply passed through to the ::open signal. It is intended to be used by applications that have multiple modes for opening files (eg: "view" vs "edit", etc). Unless you have a need for this functionality, you should use "".
The application must be registered before calling this function and it must have the %G_APPLICATION_HANDLES_OPEN flag set.
Adds a description to the application option context.
See g_option_context_set_description() for more information.
Sets the parameter string to be used by the commandline handling of application.
This function registers the argument to be passed to g_option_context_new() when the internal #GOptionContext of application is created.
See g_option_context_new() for more information about parameter_string.
Adds a summary to the application option context.
See g_option_context_set_summary() for more information.
Immediately quits the application.
Upon return to the mainloop, g_application_run() will return, calling only the 'shutdown' function before doing so.
The hold count is ignored. Take care if your code has called g_application_hold() on the application and is therefore still expecting it to exist. (Note that you may have called g_application_hold() indirectly, for example through gtk_application_add_window().)
The result of calling g_application_run() again after it returns is unspecified.
Attempts registration of the application.
This is the point at which the application discovers if it is the primary instance or merely acting as a remote for an already-existing primary instance. This is implemented by attempting to acquire the application identifier as a unique bus name on the session bus using GDBus.
If there is no application ID or if %G_APPLICATION_NON_UNIQUE was given, then this process will always become the primary instance.
Due to the internal architecture of GDBus, method calls can be dispatched at any time (even if a main loop is not running). For this reason, you must ensure that any object paths that you wish to register are registered before calling this function.
If the application has already been registered then true
is
returned with no work performed.
The #GApplication::startup signal is emitted if registration succeeds and application is the primary instance (including the non-unique case).
In the event of an error (such as cancellable being cancelled, or a
failure to connect to the session bus), false
is returned and error
is set appropriately.
Note: the return value of this function is not an indicator that this instance is or is not the primary instance of the application. See g_application_get_is_remote() for that.
Decrease the use count of application.
When the use count reaches zero, the application will stop running.
Never call this function except to cancel the effect of a previous call to g_application_hold().
Gets the resource base path of application.
See g_application_set_resource_base_path() for more information.
Sets (or unsets) the base resource path of application.
The path is used to automatically load various [application resources][gresource] such as menu layouts and action descriptions. The various types of resources will be found at fixed names relative to the given base path.
By default, the resource base path is determined from the application ID by prefixing '/' and replacing each '.' with '/'. This is done at the time that the #GApplication object is constructed. Changes to the application ID after that point will not have an impact on the resource base path.
As an example, if the application has an ID of "org.example.app" then the default resource base path will be "/org/example/app". If this is a #Gtk::Application (and you have not manually changed the path) then Gtk will then search for the menus of the application at "/org/example/app/gtk/menus.ui".
See #GResource for more information about adding resources to your application.
You can disable automatic resource loading functionality by setting
the path to nil
.
Changing the resource base path once the application is running is not recommended. The point at which the resource path is consulted for forming paths for various purposes is unspecified. When writing a sub-class of #GApplication you should either set the #GApplication:resource-base-path property at construction time, or call this function during the instance initialization. Alternatively, you can call this function in the #GApplicationClass.startup virtual function, before chaining up to the parent implementation.
Same as #resource_base_path
, but can return nil.
Runs the application.
This function is intended to be run from main() and its return value
is intended to be returned by main(). Although you are expected to pass
the argc, argv parameters from main() to this function, it is possible
to pass nil
if argv is not available or commandline handling is not
required. Note that on Windows, argc and argv are ignored, and
g_win32_get_command_line() is called internally (for proper support
of Unicode commandline arguments).
#GApplication will attempt to parse the commandline arguments. You can add commandline flags to the list of recognised options by way of g_application_add_main_option_entries(). After this, the #GApplication::handle-local-options signal is emitted, from which the application can inspect the values of its #GOptionEntrys.
#GApplication::handle-local-options is a good place to handle options
such as --version
, where an immediate reply from the local process is
desired (instead of communicating with an already-running instance).
A #GApplication::handle-local-options handler can stop further processing
by returning a non-negative value, which then becomes the exit status of
the process.
What happens next depends on the flags: if %G_APPLICATION_HANDLES_COMMAND_LINE was specified then the remaining commandline arguments are sent to the primary instance, where a #GApplication::command-line signal is emitted. Otherwise, the remaining commandline arguments are assumed to be a list of files. If there are no files listed, the application is activated via the #GApplication::activate signal. If there are one or more files, and %G_APPLICATION_HANDLES_OPEN was specified then the files are opened via the #GApplication::open signal.
If you are interested in doing more complicated local handling of the
commandline then you should implement your own #GApplication subclass
and override local_command_line(). In this case, you most likely want
to return true
from your local_command_line() implementation to
suppress the default handling. See
[gapplication-example-cmdline2.c][https://gitlab.gnome.org/GNOME/glib/-/blob/HEAD/gio/tests/gapplication-example-cmdline2.c]
for an example.
If, after the above is done, the use count of the application is zero then the exit status is returned immediately. If the use count is non-zero then the default main context is iterated until the use count falls to zero, at which point 0 is returned.
If the %G_APPLICATION_IS_SERVICE flag is set, then the service will run for as much as 10 seconds with a use count of zero while waiting for the message that caused the activation to arrive. After that, if the use count falls to zero the application will exit immediately, except in the case that g_application_set_inactivity_timeout() is in use.
This function sets the prgname (g_set_prgname()), if not already set, to the basename of argv[0].
Much like g_main_loop_run(), this function will acquire the main context for the duration that the application is running.
Since 2.40, applications that are not explicitly flagged as services or launchers (ie: neither %G_APPLICATION_IS_SERVICE or %G_APPLICATION_IS_LAUNCHER are given as flags) will check (from the default handler for local_command_line) if "--gapplication-service" was given in the command line. If this flag is present then normal commandline processing is interrupted and the %G_APPLICATION_IS_SERVICE flag is set. This provides a "compromise" solution whereby running an application directly from the commandline will invoke it in the normal way (which can be useful for debugging) while still allowing applications to be D-Bus activated in service mode. The D-Bus service file should invoke the executable with "--gapplication-service" as the sole commandline argument. This approach is suitable for use by most graphical applications but should not be used from applications like editors that need precise control over when processes invoked via the commandline will exit and what their exit status will be.
Invoke Application#run
with the process argc/argv.
If no commandline handling is required you can invoke Application#run(nil)
Sends a notification on behalf of application to the desktop shell. There is no guarantee that the notification is displayed immediately, or even at all.
Notifications may persist after the application exits. It will be D-Bus-activated when the notification or one of its actions is activated.
Modifying notification after this call has no effect. However, the object can be reused for a later call to this function. id may be any string that uniquely identifies the event for the application. It does not need to be in any special format. For example, "new-message" might be appropriate for a notification about new messages.
If a previous notification was sent with the same id, it will be
replaced with notification and shown again as if it was a new
notification. This works even for notifications sent from a previous
execution of the application, as long as id is the same string.
id may be nil
, but it is impossible to replace or withdraw
notifications without an id.
If notification is no longer relevant, it can be withdrawn with g_application_withdraw_notification().
Sets or unsets the default application for the process, as returned by g_application_get_default().
This function does not take its own reference on application. If application is destroyed then the default application will revert
back to nil
.
Destroys a binding between property and the busy state of application that was previously created with g_application_bind_busy_property().
Decreases the busy count of application.
When the busy count reaches zero, the new state will be propagated to other processes.
This function must only be called to cancel the effect of a previous call to g_application_mark_busy().
Withdraws a notification that was sent with g_application_send_notification().
This call does nothing if a notification with id doesn't exist or the notification was never sent.
This function works even for notifications sent in previous executions of this application, as long id is the same as it was for the sent notification.
Note that notifications are dismissed when the user clicks on one of the buttons in a notification or triggers its default action, so there is no need to explicitly withdraw the notification in that case.