Trait EventLoopExtDesktop

pub trait EventLoopExtDesktop {
    type UserEvent;

    // Required method
    fn run_return<F>(&mut self, event_handler: F)
       where F: FnMut(Event<'_, Self::UserEvent>, &EventLoopWindowTarget<Self::UserEvent>, &mut ControlFlow);
}

Additional methods on EventLoop that are specific to desktop platforms.

Required Associated Types

type UserEvent

A type provided by the user that can be passed through Event::UserEvent.

Required Methods

fn run_return<F>(&mut self, event_handler: F)

where F: FnMut(Event<'_, Self::UserEvent>, &EventLoopWindowTarget<Self::UserEvent>, &mut ControlFlow),

Initializes the winit event loop.

Unlike run, this function accepts non-'static (i.e. non-move) closures and returns control flow to the caller when control_flow is set to ControlFlow::Exit.

Caveats

Despite its apperance at first glance, this is not a perfect replacement for poll_events. For example, this function will not return on Windows or macOS while a window is getting resized, resulting in all application logic outside of the event_handler closure not running until the resize operation ends. Other OS operations may also result in such freezes. This behavior is caused by fundamental limitations in the underyling OS APIs, which cannot be hidden by Winit without severe stability reprecussions.

You are strongly encouraged to use run, unless the use of this is absolutely necessary.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<T> EventLoopExtDesktop for EventLoop<T>

type UserEvent = T