Struct EventLoop

pub struct EventLoop { /* private fields */ }

Provides a way to retrieve events from the system and from the windows that were registered to the events loop.

An EventLoop can be seen more or less as a “context”. Calling EventLoop::new initializes everything that will be required to create windows. For example on Linux creating an event loop opens a connection to the X or Wayland server.

To wake up an EventLoop from a another thread, see the EventLoopProxy docs.

Note that this cannot be shared across threads (due to platform-dependant logic forbidding it), as such it is neither Send nor Sync. If you need cross-thread access, the Window created from this can be sent to an other thread, and the EventLoopProxy allows you to wake up an EventLoop from another thread.

Implementations

impl EventLoop

pub fn new() -> Result<EventLoop, EventLoopError>

Create the event loop.

This is an alias of EventLoop::builder().build().

pub fn builder() -> EventLoopBuilder

Start building a new event loop.

This returns an EventLoopBuilder, to allow configuring the event loop before creation.

To get the actual event loop, call build on that.

impl EventLoop

pub fn run_app<A: ApplicationHandler>( self, app: A, ) -> Result<(), EventLoopError>

Run the application with the event loop on the calling thread.

See the set_control_flow() docs on how to change the event loop’s behavior.

Platform-specific

• iOS: Will never return to the caller and so values not passed to this function will not be dropped before the process exits.

• Web: Will act as if it never returns to the caller by throwing a Javascript exception (that Rust doesn’t see) that will also mean that the rest of the function is never executed and any values not passed to this function will not be dropped.

  Web applications are recommended to use EventLoopExtWeb::spawn_app() ¹ instead of run_app() to avoid the need for the Javascript exception trick, and to make it clearer that the event loop runs asynchronously (via the browser’s own, internal, event loop) and doesn’t block the current thread of execution like it does on other platforms.

  This function won’t be available with target_feature = "exception-handling".

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1. spawn_app() is only available on the Web platform. ↩

pub fn create_proxy(&self) -> EventLoopProxy

Creates an EventLoopProxy that can be used to dispatch user events to the main event loop, possibly from another thread.

pub fn owned_display_handle(&self) -> OwnedDisplayHandle

Gets a persistent reference to the underlying platform display.

See the OwnedDisplayHandle type for more information.

pub fn listen_device_events(&self, allowed: DeviceEvents)

Change if or when DeviceEvents are captured.

See ActiveEventLoop::listen_device_events for details.

pub fn set_control_flow(&self, control_flow: ControlFlow)

Sets the ControlFlow.

pub fn create_custom_cursor( &self, custom_cursor: CustomCursorSource, ) -> Result<CustomCursor, RequestError>

Create custom cursor.

Platform-specific

iOS / Android / Orbital: Unsupported.

Trait Implementations

impl AsFd for EventLoop

fn as_fd(&self) -> BorrowedFd<'_>

Get the underlying EventLoop’s fd which you can register into other event loop, like calloop or mio. When doing so, the loop must be polled with the pump_app_events API.

impl AsRawFd for EventLoop

fn as_raw_fd(&self) -> RawFd

Get the underlying EventLoop’s raw fd which you can register into other event loop, like calloop or mio. When doing so, the loop must be polled with the pump_app_events API.

impl Debug for EventLoop

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

Formats the value using the given formatter.

impl EventLoopExtPumpEvents for EventLoop

fn pump_app_events<A: ApplicationHandler>( &mut self, timeout: Option<Duration>, app: A, ) -> PumpStatus

Pump the EventLoop to check for and dispatch pending events.

impl EventLoopExtRunOnDemand for EventLoop

fn run_app_on_demand<A: ApplicationHandler>( &mut self, app: A, ) -> Result<(), EventLoopError>

Run the application with the event loop on the calling thread.

impl EventLoopExtWayland for EventLoop

fn is_wayland(&self) -> bool

True if the EventLoop uses Wayland.

impl EventLoopExtX11 for EventLoop

fn is_x11(&self) -> bool

True if the EventLoop uses X11.

impl HasDisplayHandle for EventLoop

fn display_handle(&self) -> Result<DisplayHandle<'_>, HandleError>

Get a handle to the display controller of the windowing system.