macOS: add function to hide other applications

CHANGELOG.md

@@ -2,6 +2,7 @@
 - On Web, prevent the webpage from scrolling when the user is focused on a winit canvas
 
 - On Wayland, fix deadlock when calling to `set_inner_size` from a callback.
+- On macOS, add `hide__other_applications` to `EventLoopWindowTarget` via existing `EventLoopWindowTargetExtMacOS` trait. `hide_other_applications` will hide other applications by calling `-[NSApplication hideOtherApplications: nil]`.
 
 # 0.22.2 (2020-05-16)
 

src/platform/macos.rs

@@ -215,6 +215,8 @@ impl MonitorHandleExtMacOS for MonitorHandle {
 pub trait EventLoopWindowTargetExtMacOS {
     /// Hide the entire application. In most applications this is typically triggered with Command-H.
     fn hide_application(&self);
+    /// Hide the other applications. In most applications this is typically triggered with Command+Option-H.
+    fn hide_other_applications(&self);
 }
 
 impl<T> EventLoopWindowTargetExtMacOS for EventLoopWindowTarget<T> {
@@ -223,4 +225,10 @@ impl<T> EventLoopWindowTargetExtMacOS for EventLoopWindowTarget<T> {
         let app: cocoa::base::id = unsafe { msg_send![cls, sharedApplication] };
         unsafe { msg_send![app, hide: 0] }
     }
+
+    fn hide_other_applications(&self) {
+        let cls = objc::runtime::Class::get("NSApplication").unwrap();
+        let app: cocoa::base::id = unsafe { msg_send![cls, sharedApplication] };
+        unsafe { msg_send![app, hideOtherApplications: 0] }
+    }
 }