Add StartCause::Init support, timer example

examples/timer.rs

@@ -0,0 +1,33 @@
+extern crate winit;
+use std::time::{Duration, Instant};
+
+fn main() {
+    let events_loop = winit::EventLoop::new();
+
+    let _window = winit::WindowBuilder::new()
+        .with_title("A fantastic window!")
+        .build(&events_loop)
+        .unwrap();
+
+    events_loop.run(move |event, _, control_flow| {
+        println!("{:?}", event);
+
+        match event {
+            winit::Event::NewEvents(winit::StartCause::Init) =>
+                *control_flow = winit::ControlFlow::WaitTimeout(Duration::new(1, 0)),
+            winit::Event::NewEvents(winit::StartCause::TimeoutExpired{..}) => {
+                *control_flow = winit::ControlFlow::WaitTimeout(Duration::new(1, 0));
+                println!("\nTimer\n");
+            },
+            winit::Event::NewEvents(winit::StartCause::WaitCancelled{start, requested_duration}) => {
+                println!("{:?}", Instant::now() - start);
+                *control_flow = winit::ControlFlow::WaitTimeout(requested_duration.unwrap().checked_sub(Instant::now() - start).unwrap_or(Duration::new(0, 0)));
+            }
+            winit::Event::WindowEvent {
+                event: winit::WindowEvent::CloseRequested,
+                ..
+            } => *control_flow = winit::ControlFlow::Exit,
+            _ => ()
+        }
+    });
+}