pub struct DebugControllerDBus { /* private fields */ }
Available on crate feature v2_72 only.
Expand description

GDebugControllerDBus is an implementation of DebugController which exposes debug settings as a D-Bus object.

It is a Initable object, and will register an object at /org/gtk/Debugging on the bus given as connection once it’s initialized. The object will be unregistered when the last reference to the GDebugControllerDBus is dropped.

This D-Bus object can be used by remote processes to enable or disable debug output in this process. Remote processes calling org.gtk.Debugging.SetDebugEnabled() will affect the value of debug-enabled and, by default, log_get_debug_enabled().

By default, no processes are allowed to call SetDebugEnabled() unless a authorize signal handler is installed. This is because the process may be privileged, or might expose sensitive information in its debug output. You may want to restrict the ability to enable debug output to privileged users or processes.

One option is to install a D-Bus security policy which restricts access to SetDebugEnabled(), installing something like the following in $datadir/dbus-1/system.d/:

<?xml version="1.0"?> <!--*-nxml-*-->
<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
     "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>
  <policy user="root">
    <allow send_destination="com.example.MyService" send_interface="org.gtk.Debugging"/>
  </policy>
  <policy context="default">
    <deny send_destination="com.example.MyService" send_interface="org.gtk.Debugging"/>
  </policy>
</busconfig>

This will prevent the SetDebugEnabled() method from being called by all except root. It will not prevent the DebugEnabled property from being read, as it’s accessed through the org.freedesktop.DBus.Properties interface.

Another option is to use polkit to allow or deny requests on a case-by-case basis, allowing for the possibility of dynamic authorisation. To do this, connect to the authorize signal and query polkit in it:

⚠️ The following code is in c ⚠️

  g_autoptr(GError) child_error = NULL;
  g_autoptr(GDBusConnection) connection = g_bus_get_sync (G_BUS_TYPE_SYSTEM, NULL, NULL);
  gulong debug_controller_authorize_id = 0;

  // Set up the debug controller.
  debug_controller = G_DEBUG_CONTROLLER (g_debug_controller_dbus_new (priv->connection, NULL, &child_error));
  if (debug_controller == NULL)
    {
      g_error ("Could not register debug controller on bus: %s"),
               child_error->message);
    }

  debug_controller_authorize_id = g_signal_connect (debug_controller,
                                                    "authorize",
                                                    G_CALLBACK (debug_controller_authorize_cb),
                                                    self);

  static gboolean
  debug_controller_authorize_cb (GDebugControllerDBus  *debug_controller,
                                 GDBusMethodInvocation *invocation,
                                 gpointer               user_data)
  {
    g_autoptr(PolkitAuthority) authority = NULL;
    g_autoptr(PolkitSubject) subject = NULL;
    g_autoptr(PolkitAuthorizationResult) auth_result = NULL;
    g_autoptr(GError) local_error = NULL;
    GDBusMessage *message;
    GDBusMessageFlags message_flags;
    PolkitCheckAuthorizationFlags flags = POLKIT_CHECK_AUTHORIZATION_FLAGS_NONE;

    message = g_dbus_method_invocation_get_message (invocation);
    message_flags = g_dbus_message_get_flags (message);

    authority = polkit_authority_get_sync (NULL, &local_error);
    if (authority == NULL)
      {
        g_warning ("Failed to get polkit authority: %s", local_error->message);
        return FALSE;
      }

    if (message_flags & G_DBUS_MESSAGE_FLAGS_ALLOW_INTERACTIVE_AUTHORIZATION)
      flags |= POLKIT_CHECK_AUTHORIZATION_FLAGS_ALLOW_USER_INTERACTION;

    subject = polkit_system_bus_name_new (g_dbus_method_invocation_get_sender (invocation));

    auth_result = polkit_authority_check_authorization_sync (authority,
                                                             subject,
                                                             "com.example.MyService.set-debug-enabled",
                                                             NULL,
                                                             flags,
                                                             NULL,
                                                             &local_error);
    if (auth_result == NULL)
      {
        g_warning ("Failed to get check polkit authorization: %s", local_error->message);
        return FALSE;
      }

    return polkit_authorization_result_get_is_authorized (auth_result);
  }

§Properties

§connection

The D-Bus connection to expose the debugging interface on.

Typically this will be the same connection (to the system or session bus) which the rest of the application or service’s D-Bus objects are registered on.

Readable | Writeable | Construct Only

DebugController

§debug-enabled

true if debug output should be exposed (for example by forwarding it to the journal), false otherwise.

Readable | Writeable

§Signals

§authorize

Emitted when a D-Bus peer is trying to change the debug settings and used to determine if that is authorized.

This signal is emitted in a dedicated worker thread, so handlers are allowed to perform blocking I/O. This means that, for example, it is appropriate to call polkit_authority_check_authorization_sync() to check authorization using polkit.

If false is returned then no further handlers are run and the request to change the debug settings is rejected.

Otherwise, if true is returned, signal emission continues. If no handlers return false, then the debug settings are allowed to be changed.

Signal handlers must not modify @invocation, or cause it to return a value.

The default class handler just returns true.

§Implements

DebugControllerDBusExt, [trait@glib::ObjectExt], DebugControllerExt, InitableExt, DebugControllerDBusExtManual

Implementations§

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impl DebugControllerDBus

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pub const NONE: Option<&'static DebugControllerDBus> = None

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pub fn new( connection: &DBusConnection, cancellable: Option<&impl IsA<Cancellable>> ) -> Result<Option<DebugControllerDBus>, Error>

Create a new #GDebugControllerDBus and synchronously initialize it.

Initializing the object will export the debug object on @connection. The object will remain registered until the last reference to the #GDebugControllerDBus is dropped.

Initialization may fail if registering the object on @connection fails.

§connection

a #GDBusConnection to register the debug object on

§cancellable

a #GCancellable, or None

§Returns

a new #GDebugControllerDBus, or None on failure

Trait Implementations§

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impl Clone for DebugControllerDBus

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fn clone(&self) -> Self

Returns a copy of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for DebugControllerDBus

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl HasParamSpec for DebugControllerDBus

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type ParamSpec = ParamSpecObject

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type SetValue = DebugControllerDBus

Preferred value to be used as setter for the associated ParamSpec.
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type BuilderFn = fn(_: &str) -> ParamSpecObjectBuilder<'_, DebugControllerDBus>

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fn param_spec_builder() -> Self::BuilderFn

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impl Hash for DebugControllerDBus

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fn hash<H>(&self, state: &mut H)
where H: Hasher,

Feeds this value into the given Hasher. Read more
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fn hash_slice<H>(data: &[Self], state: &mut H)
where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl Ord for DebugControllerDBus

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fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other. Read more
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fn max(self, other: Self) -> Self
where Self: Sized,

Compares and returns the maximum of two values. Read more
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fn min(self, other: Self) -> Self
where Self: Sized,

Compares and returns the minimum of two values. Read more
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fn clamp(self, min: Self, max: Self) -> Self
where Self: Sized + PartialOrd,

Restrict a value to a certain interval. Read more
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impl ParentClassIs for DebugControllerDBus

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impl<OT: ObjectType> PartialEq<OT> for DebugControllerDBus

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fn eq(&self, other: &OT) -> bool

This method tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl<OT: ObjectType> PartialOrd<OT> for DebugControllerDBus

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fn partial_cmp(&self, other: &OT) -> Option<Ordering>

This method returns an ordering between self and other values if one exists. Read more
1.0.0 · source§

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator. Read more
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fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
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fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator. Read more
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fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more
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impl StaticType for DebugControllerDBus

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fn static_type() -> Type

Returns the type identifier of Self.
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impl Eq for DebugControllerDBus

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impl IsA<DebugController> for DebugControllerDBus

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impl IsA<Initable> for DebugControllerDBus

Auto Trait Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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Mutably borrows from an owned value. Read more
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Upcasts an object to a reference of its superclass or interface T. Read more
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Tries to downcast to a subclass or interface implementor T. Read more
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Tries to downcast to a reference of its subclass or interface implementor T. Read more
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Tries to cast to an object of type T. This handles upcasting, downcasting and casting between interface and interface implementors. All checks are performed at runtime, while upcast will do many checks at compile-time already. downcast will perform the same checks at runtime as dynamic_cast, but will also ensure some amount of compile-time safety. Read more
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where T: ObjectType,

Tries to cast to reference to an object of type T. This handles upcasting, downcasting and casting between interface and interface implementors. All checks are performed at runtime, while downcast and upcast will do many checks at compile-time already. Read more
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unsafe fn unsafe_cast<T>(self) -> T
where T: ObjectType,

Casts to T unconditionally. Read more
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unsafe fn unsafe_cast_ref<T>(&self) -> &T
where T: ObjectType,

Casts to &T unconditionally. Read more
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impl<O> DebugControllerDBusExt for O

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fn stop(&self)

Available on crate feature v2_72 only.
Stop the debug controller, unregistering its object from the bus. Read more
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fn connect_authorize<F: Fn(&Self, &DBusMethodInvocation) -> bool + 'static>( &self, f: F ) -> SignalHandlerId

Available on crate feature v2_72 only.
Emitted when a D-Bus peer is trying to change the debug settings and used to determine if that is authorized. Read more
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impl<O> DebugControllerDBusExtManual for O

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fn connection(&self) -> DBusConnection

Available on crate feature v2_72 only.
The D-Bus connection to expose the debugging interface on. Read more
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impl<O> DebugControllerExt for O
where O: IsA<DebugController>,

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fn is_debug_enabled(&self) -> bool

Available on crate feature v2_72 only.
Get the value of #GDebugController:debug-enabled. Read more
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fn set_debug_enabled(&self, debug_enabled: bool)

Available on crate feature v2_72 only.
Set the value of #GDebugController:debug-enabled. Read more
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fn connect_debug_enabled_notify<F: Fn(&Self) + 'static>( &self, f: F ) -> SignalHandlerId

Available on crate feature v2_72 only.
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T> FromGlibContainerAsVec<<T as GlibPtrDefault>::GlibType, *const GList> for T

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impl<T> FromGlibContainerAsVec<<T as GlibPtrDefault>::GlibType, *mut GList> for T

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impl<T> FromGlibContainerAsVec<<T as GlibPtrDefault>::GlibType, *mut GSList> for T

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impl<T> FromGlibPtrArrayContainerAsVec<<T as GlibPtrDefault>::GlibType, *mut GPtrArray> for T

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impl<O> InitableExt for O
where O: IsA<Initable>,

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unsafe fn init( &self, cancellable: Option<&impl IsA<Cancellable>> ) -> Result<(), Error>

Initializes the object implementing the interface. Read more
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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> IntoClosureReturnValue for T
where T: Into<Value>,

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where T: ObjectType,

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where U: StaticType,

Returns true if the object is an instance of (can be cast to) T.
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Returns the type of the object.
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Returns the ObjectClass of the object. Read more
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where T: IsClass,

Returns the class of the object.
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where U: IsClass,

Returns the class of the object in the given type T. Read more
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where U: IsInterface,

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fn set_property(&self, property_name: &str, value: impl Into<Value>)

Sets the property property_name of the object to value value. Read more
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fn set_property_from_value(&self, property_name: &str, value: &Value)

Sets the property property_name of the object to value value. Read more
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fn set_properties(&self, property_values: &[(&str, &dyn ToValue)])

Sets multiple properties of the object at once. Read more
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fn set_properties_from_value(&self, property_values: &[(&str, Value)])

Sets multiple properties of the object at once. Read more
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fn property<V>(&self, property_name: &str) -> V
where V: for<'b> FromValue<'b> + 'static,

Gets the property property_name of the object and cast it to the type V. Read more
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fn property_value(&self, property_name: &str) -> Value

Gets the property property_name of the object. Read more
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fn has_property(&self, property_name: &str, type_: Option<Type>) -> bool

Check if the object has a property property_name of the given type_. Read more
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Get the type of the property property_name of this object. Read more
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fn find_property(&self, property_name: &str) -> Option<ParamSpec>

Get the ParamSpec of the property property_name of this object.
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fn list_properties(&self) -> PtrSlice<ParamSpec>

Return all ParamSpec of the properties of this object.
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fn freeze_notify(&self) -> PropertyNotificationFreezeGuard

Freeze all property notifications until the return guard object is dropped. Read more
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unsafe fn set_qdata<QD>(&self, key: Quark, value: QD)
where QD: 'static,

Set arbitrary data on this object with the given key. Read more
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unsafe fn qdata<QD>(&self, key: Quark) -> Option<NonNull<QD>>
where QD: 'static,

Return previously set arbitrary data of this object with the given key. Read more
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unsafe fn steal_qdata<QD>(&self, key: Quark) -> Option<QD>
where QD: 'static,

Retrieve previously set arbitrary data of this object with the given key. Read more
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unsafe fn set_data<QD>(&self, key: &str, value: QD)
where QD: 'static,

Set arbitrary data on this object with the given key. Read more
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unsafe fn data<QD>(&self, key: &str) -> Option<NonNull<QD>>
where QD: 'static,

Return previously set arbitrary data of this object with the given key. Read more
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unsafe fn steal_data<QD>(&self, key: &str) -> Option<QD>
where QD: 'static,

Retrieve previously set arbitrary data of this object with the given key. Read more
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fn block_signal(&self, handler_id: &SignalHandlerId)

Block a given signal handler. Read more
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fn unblock_signal(&self, handler_id: &SignalHandlerId)

Unblock a given signal handler.
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fn stop_signal_emission(&self, signal_id: SignalId, detail: Option<Quark>)

Stop emission of the currently emitted signal.
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fn stop_signal_emission_by_name(&self, signal_name: &str)

Stop emission of the currently emitted signal by the (possibly detailed) signal name.
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fn connect<F>( &self, signal_name: &str, after: bool, callback: F ) -> SignalHandlerId
where F: Fn(&[Value]) -> Option<Value> + Send + Sync + 'static,

Connect to the signal signal_name on this object. Read more
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fn connect_id<F>( &self, signal_id: SignalId, details: Option<Quark>, after: bool, callback: F ) -> SignalHandlerId
where F: Fn(&[Value]) -> Option<Value> + Send + Sync + 'static,

Connect to the signal signal_id on this object. Read more
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fn connect_local<F>( &self, signal_name: &str, after: bool, callback: F ) -> SignalHandlerId
where F: Fn(&[Value]) -> Option<Value> + 'static,

Connect to the signal signal_name on this object. Read more
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fn connect_local_id<F>( &self, signal_id: SignalId, details: Option<Quark>, after: bool, callback: F ) -> SignalHandlerId
where F: Fn(&[Value]) -> Option<Value> + 'static,

Connect to the signal signal_id on this object. Read more
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unsafe fn connect_unsafe<F>( &self, signal_name: &str, after: bool, callback: F ) -> SignalHandlerId
where F: Fn(&[Value]) -> Option<Value>,

Connect to the signal signal_name on this object. Read more
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unsafe fn connect_unsafe_id<F>( &self, signal_id: SignalId, details: Option<Quark>, after: bool, callback: F ) -> SignalHandlerId
where F: Fn(&[Value]) -> Option<Value>,

Connect to the signal signal_id on this object. Read more
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fn connect_closure( &self, signal_name: &str, after: bool, closure: RustClosure ) -> SignalHandlerId

Connect a closure to the signal signal_name on this object. Read more
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fn connect_closure_id( &self, signal_id: SignalId, details: Option<Quark>, after: bool, closure: RustClosure ) -> SignalHandlerId

Connect a closure to the signal signal_id on this object. Read more
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fn watch_closure(&self, closure: &impl AsRef<Closure>)

Limits the lifetime of closure to the lifetime of the object. When the object’s reference count drops to zero, the closure will be invalidated. An invalidated closure will ignore any calls to invoke_with_values, or invoke when using Rust closures.
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fn emit<R>(&self, signal_id: SignalId, args: &[&dyn ToValue]) -> R

Emit signal by signal id. Read more
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fn emit_with_values(&self, signal_id: SignalId, args: &[Value]) -> Option<Value>

Same as Self::emit but takes Value for the arguments.
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fn emit_by_name<R>(&self, signal_name: &str, args: &[&dyn ToValue]) -> R

Emit signal by its name. Read more
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fn emit_by_name_with_values( &self, signal_name: &str, args: &[Value] ) -> Option<Value>

Emit signal by its name. Read more
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fn emit_by_name_with_details<R>( &self, signal_name: &str, details: Quark, args: &[&dyn ToValue] ) -> R

Emit signal by its name with details. Read more
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fn emit_by_name_with_details_and_values( &self, signal_name: &str, details: Quark, args: &[Value] ) -> Option<Value>

Emit signal by its name with details. Read more
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fn emit_with_details<R>( &self, signal_id: SignalId, details: Quark, args: &[&dyn ToValue] ) -> R

Emit signal by signal id with details. Read more
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fn emit_with_details_and_values( &self, signal_id: SignalId, details: Quark, args: &[Value] ) -> Option<Value>

Emit signal by signal id with details. Read more
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fn disconnect(&self, handler_id: SignalHandlerId)

Disconnect a previously connected signal handler.
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fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId
where F: Fn(&T, &ParamSpec) + Send + Sync + 'static,

Connect to the notify signal of the object. Read more
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fn connect_notify_local<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId
where F: Fn(&T, &ParamSpec) + 'static,

Connect to the notify signal of the object. Read more
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unsafe fn connect_notify_unsafe<F>( &self, name: Option<&str>, f: F ) -> SignalHandlerId
where F: Fn(&T, &ParamSpec),

Connect to the notify signal of the object. Read more
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fn notify(&self, property_name: &str)

Notify that the given property has changed its value. Read more
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fn notify_by_pspec(&self, pspec: &ParamSpec)

Notify that the given property has changed its value. Read more
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fn downgrade(&self) -> WeakRef<T>

Downgrade this object to a weak reference.
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fn add_weak_ref_notify<F>(&self, f: F) -> WeakRefNotify<T>
where F: FnOnce() + Send + 'static,

Add a callback to be notified when the Object is disposed.
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fn bind_property<'f, 't, O, 'a>( &'a self, source_property: &'a str, target: &'a O, target_property: &'a str ) -> BindingBuilder<'a, 'f, 't>
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Bind property source_property on this object to the target_property on the target object. Read more
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fn ref_count(&self) -> u32

Returns the strong reference count of this object.
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Runs the dispose mechanism of the object. Read more
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impl<T> Property for T
where T: HasParamSpec,

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type Value = T

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impl<T> PropertyGet for T
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type Value = T

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fn get<R, F>(&self, f: F) -> R
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fn ensure_type()

Ensures that the type has been registered with the type system.
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The resulting type after obtaining ownership.
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type Error = Infallible

The type returned in the event of a conversion error.
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Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<'a, T, C, E> FromValueOptional<'a> for T
where T: FromValue<'a, Checker = C>, C: ValueTypeChecker<Error = ValueTypeMismatchOrNoneError<E>>, E: Error + Send + 'static,

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impl<Super, Sub> MayDowncastTo<Sub> for Super
where Super: IsA<Super>, Sub: IsA<Super>,