Struct wayland_client::backend::Handle

pub struct Handle { /* private fields */ }

Main handle of a backend to the Wayland protocol

This type hosts most of the protocol-related functionality of the backend, and is the main entry point for manipulating Wayland objects. It can be retrieved both from the backend via Backend::handle(), and is given to you as argument in most event callbacks.

Implementations

impl Handle

pub fn display_id(&self) -> ObjectId

Get the object ID for the wl_display

pub fn last_error(&self) -> Option<WaylandError>

Get the last error that occurred on this backend

If this returns an error, your Wayland connection is already dead.

pub fn info(&self, id: ObjectId) -> Result<ObjectInfo, InvalidId>

Get the detailed information about a wayland object

Returns an error if the provided object ID is no longer valid.

pub fn null_id(&mut self) -> ObjectId

Create a null object ID

This object ID is always invalid, and can be used as placeholder.

pub fn placeholder_id(
    &mut self,
    spec: Option<(&'static Interface, u32)>
) -> ObjectId

Create a placeholder ID for object creation

This ID needs to be created beforehand and given as argument to a request creating a new object ID. A specification must be specified if the interface and version cannot be inferred from the protocol (for example object creation from the wl_registry).

If a specification is provided it’ll be checked against what can be deduced from the protocol specification, and send_request will panic if they do not match.

pub fn send_request(
    &mut self,
    msg: Message<ObjectId>,
    data: Option<Arc<dyn ObjectData + 'static>>
) -> Result<ObjectId, InvalidId>

Sends a request to the server

Returns an error if the sender ID of the provided message is no longer valid.

Panic:

Several checks against the protocol specification are done, and this method will panic if they do not pass:

• the message opcode must be valid for the sender interface
• the argument list must match the prototype for the message associated with this opcode
• if the method creates a new object, a placeholder_id() must be given in the argument list, either without a specification, or with a specification that matches the interface and version deduced from the protocol rules

pub fn get_data(
    &self,
    id: ObjectId
) -> Result<Arc<dyn ObjectData + 'static>, InvalidId>

Access the object data associated with a given object ID

Returns an error if the object ID is not longer valid or if it corresponds to a Wayland object that is not managed by this backend (when multiple libraries share the same Wayland socket via libwayland if using the system backend).

pub fn set_data(
    &mut self,
    id: ObjectId,
    data: Arc<dyn ObjectData + 'static>
) -> Result<(), InvalidId>

Set the object data associated with a given object ID

Returns an error if the object ID is not longer valid or if it corresponds to a Wayland object that is not managed by this backend (when multiple libraries share the same Wayland socket via libwayland if using the system backend).

Trait Implementations

impl Debug for Handle

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

Formats the value using the given formatter.

impl<'a> From<&'a mut Handle> for ConnectionHandle<'a>

fn from(handle: &'a mut Handle) -> Self

Creates a ConnectionHandle using a &mut Handle from wayland-backend.