Struct TypePlugin

pub struct TypePlugin { /* private fields */ }

An interface that handles the lifecycle of dynamically loaded types.

The GObject type system supports dynamic loading of types. It goes as follows:

1. The type is initially introduced (usually upon loading the module the first time, or by your main application that knows what modules introduces what types), like this: ⚠️ The following code is in c ⚠️

   new_type_id = g_type_register_dynamic (parent_type_id,
                                          "TypeName",
                                          new_type_plugin,
                                          type_flags);
   ```
 where `new_type_plugin` is an implementation of the
 `GTypePlugin` interface.

2. The type's implementation is referenced, e.g. through
 [func[`Object`][crate::Object].ref] or through [func[`Object`][crate::Object]]
 (this is being called by [ctor[`Object`][crate::Object].new]) or through one of the above
 done on a type derived from `new_type_id`.

3. This causes the type system to load the type's implementation by calling
 [method[`Object`][crate::Object].use] and [method[`Object`][crate::Object].complete_type_info]
 on `new_type_plugin`.

4. At some point the type's implementation isn't required anymore, e.g. after
 [method[`Object`][crate::Object].unref] or [func[`Object`][crate::Object]]
 (called when the reference count of an instance drops to zero).

5. This causes the type system to throw away the information retrieved
 from [method[`Object`][crate::Object].complete_type_info] and then it calls
 [method[`Object`][crate::Object].unuse] on `new_type_plugin`.

6. Things may repeat from the second step.

So basically, you need to implement a `GTypePlugin` type that
carries a use_count, once use_count goes from zero to one, you need
to load the implementation to successfully handle the upcoming
[method[`Object`][crate::Object].complete_type_info] call. Later, maybe after
succeeding use/unuse calls, once use_count drops to zero, you can
unload the implementation again. The type system makes sure to call
[method[`Object`][crate::Object].use] and [method[`Object`][crate::Object].complete_type_info]
again when the type is needed again.

[class[`Object`][crate::Object]] is an implementation of `GTypePlugin` that
already implements most of this except for the actual module loading and
unloading. It even handles multiple registered types per module.

# Implements

[`TypePluginExt`][trait@crate::prelude::TypePluginExt]

GLib type: GObject with reference counted clone semantics.

Implementations

impl TypePlugin

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

Trait Implementations

impl Clone for TypePlugin

fn clone(&self) -> Self

Makes a clone of this shared reference.

This increments the strong reference count of the object. Dropping the object will decrement it again.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TypePlugin

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

Formats the value using the given formatter.

impl HasParamSpec for TypePlugin

type ParamSpec = ParamSpecObject

type SetValue = TypePlugin

Preferred value to be used as setter for the associated ParamSpec.

type BuilderFn = fn(_: &str) -> ParamSpecObjectBuilder<'_, TypePlugin>

fn param_spec_builder() -> Self::BuilderFn

impl Hash for TypePlugin

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

where H: Hasher,

Hashes the memory address of this object.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: TypePluginImpl> IsImplementable<T> for TypePlugin

fn interface_init(iface: &mut Interface<Self>)

Override the virtual methods of this interface for the given subclass and do other interface initialization.

fn instance_init(_instance: &mut InitializingObject<T>)

Instance specific initialization.

impl Ord for TypePlugin

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

Comparison for two GObjects.

Compares the memory addresses of the provided objects.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

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

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

Equality for two GObjects.

Two GObjects are equal if their memory addresses are equal.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<OT: ObjectType> PartialOrd<OT> for TypePlugin

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

Partial comparison for two GObjects.

Compares the memory addresses of the provided objects.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for TypePlugin

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for TypePlugin

impl IsA<TypePlugin> for TypeModule