Add events on display add/remove.

atom.gyp

@@ -80,6 +80,7 @@
       'atom/browser/api/atom_api_protocol.cc',
       'atom/browser/api/atom_api_protocol.h',
       'atom/browser/api/atom_api_screen.cc',
+      'atom/browser/api/atom_api_screen.h',
       'atom/browser/api/atom_api_tray.cc',
       'atom/browser/api/atom_api_tray.h',
       'atom/browser/api/atom_api_web_contents.cc',

atom/browser/api/atom_api_screen.cc

@@ -2,29 +2,92 @@
 // Use of this source code is governed by the MIT license that can be
 // found in the LICENSE file.
 
+#include "atom/browser/api/atom_api_screen.h"
+
+#include "atom/browser/browser.h"
 #include "atom/common/native_mate_converters/gfx_converter.h"
 #include "base/bind.h"
 #include "native_mate/dictionary.h"
+#include "native_mate/object_template_builder.h"
 #include "ui/gfx/screen.h"
 
 #include "atom/common/node_includes.h"
 
+namespace atom {
+
+namespace api {
+
+Screen::Screen(gfx::Screen* screen) : screen_(screen) {
+}
+
+Screen::~Screen() {
+}
+
+gfx::Point Screen::GetCursorScreenPoint() {
+  return screen_->GetCursorScreenPoint();
+}
+
+gfx::Display Screen::GetPrimaryDisplay() {
+  return screen_->GetPrimaryDisplay();
+}
+
+std::vector<gfx::Display> Screen::GetAllDisplays() {
+  return screen_->GetAllDisplays();
+}
+
+gfx::Display Screen::GetDisplayNearestPoint(const gfx::Point& point) {
+  return screen_->GetDisplayNearestPoint(point);
+}
+
+gfx::Display Screen::GetDisplayMatching(const gfx::Rect& match_rect) {
+  return screen_->GetDisplayMatching(match_rect);
+}
+
+void Screen::OnDisplayAdded(const gfx::Display& new_display) {
+  Emit("display-added");
+}
+
+void Screen::OnDisplayRemoved(const gfx::Display& old_display) {
+  Emit("display-removed");
+}
+
+void Screen::OnDisplayMetricsChanged(const gfx::Display& display,
+                                     uint32_t changed_metrics) {
+  Emit("display-metrics-changed");
+}
+
+mate::ObjectTemplateBuilder Screen::GetObjectTemplateBuilder(
+    v8::Isolate* isolate) {
+  return mate::ObjectTemplateBuilder(isolate)
+      .SetMethod("getCursorScreenPoint", &Screen::GetCursorScreenPoint)
+      .SetMethod("getPrimaryDisplay", &Screen::GetPrimaryDisplay)
+      .SetMethod("getAllDisplays", &Screen::GetAllDisplays)
+      .SetMethod("getDisplayNearestPoint", &Screen::GetDisplayNearestPoint)
+      .SetMethod("getDisplayMatching", &Screen::GetDisplayMatching);
+}
+
+// static
+mate::Handle<Screen> Screen::Create(v8::Isolate* isolate) {
+  gfx::Screen* screen = gfx::Screen::GetNativeScreen();
+  if (!screen) {
+    isolate->ThrowException(v8::Exception::Error(mate::StringToV8(
+        isolate, "Failed to get screen information")));
+    return mate::Handle<Screen>();
+  }
+
+  return CreateHandle(isolate, new Screen(screen));
+}
+
+}  // namespace api
+
+}  // namespace atom
+
 namespace {
 
 void Initialize(v8::Handle<v8::Object> exports, v8::Handle<v8::Value> unused,
                 v8::Handle<v8::Context> context, void* priv) {
-  auto screen = base::Unretained(gfx::Screen::GetNativeScreen());
   mate::Dictionary dict(context->GetIsolate(), exports);
-  dict.SetMethod("getCursorScreenPoint",
+  dict.Set("screen", atom::api::Screen::Create(context->GetIsolate()));
-                 base::Bind(&gfx::Screen::GetCursorScreenPoint, screen));
-  dict.SetMethod("getPrimaryDisplay",
-                 base::Bind(&gfx::Screen::GetPrimaryDisplay, screen));
-  dict.SetMethod("getAllDisplays",
-                 base::Bind(&gfx::Screen::GetAllDisplays, screen));
-  dict.SetMethod("getDisplayNearestPoint",
-                 base::Bind(&gfx::Screen::GetDisplayNearestPoint, screen));
-  dict.SetMethod("getDisplayMatching",
-                 base::Bind(&gfx::Screen::GetDisplayMatching, screen));
 }
 
 }  // namespace

atom/browser/api/atom_api_screen.h

@@ -0,0 +1,59 @@
+// Copyright (c) 2015 GitHub, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#ifndef ATOM_BROWSER_API_ATOM_API_SCREEN_H_
+#define ATOM_BROWSER_API_ATOM_API_SCREEN_H_
+
+#include <vector>
+
+#include "atom/browser/api/event_emitter.h"
+#include "native_mate/handle.h"
+#include "ui/gfx/display_observer.h"
+
+namespace gfx {
+class Point;
+class Rect;
+class Screen;
+}
+
+namespace atom {
+
+namespace api {
+
+class Screen : public mate::EventEmitter,
+               public gfx::DisplayObserver {
+ public:
+  static mate::Handle<Screen> Create(v8::Isolate* isolate);
+
+ protected:
+  explicit Screen(gfx::Screen* screen);
+  virtual ~Screen();
+
+  gfx::Point GetCursorScreenPoint();
+  gfx::Display GetPrimaryDisplay();
+  std::vector<gfx::Display> GetAllDisplays();
+  gfx::Display GetDisplayNearestPoint(const gfx::Point& point);
+  gfx::Display GetDisplayMatching(const gfx::Rect& match_rect);
+
+  // gfx::DisplayObserver:
+  void OnDisplayAdded(const gfx::Display& new_display) override;
+  void OnDisplayRemoved(const gfx::Display& old_display) override;
+  void OnDisplayMetricsChanged(const gfx::Display& display,
+                               uint32_t changed_metrics) override;
+
+  // mate::Wrappable:
+  mate::ObjectTemplateBuilder GetObjectTemplateBuilder(
+      v8::Isolate* isolate) override;
+
+ private:
+  gfx::Screen* screen_;
+
+  DISALLOW_COPY_AND_ASSIGN(Screen);
+};
+
+}  // namespace api
+
+}  // namespace atom
+
+#endif  // ATOM_BROWSER_API_ATOM_API_SCREEN_H_

atom/browser/api/lib/screen.coffee

@@ -1,11 +1,6 @@
-binding = process.atomBinding 'screen'
+EventEmitter = require('events').EventEmitter
 
-checkAppIsReady = ->
+screen = process.atomBinding('screen').screen
-  unless process.type is 'renderer' or require('app').isReady()
+screen.__proto__ = EventEmitter.prototype
-    throw new Error('Can not use screen module before the "ready" event of app module gets emitted')
 
-for name, _ of binding
+module.exports = screen
-  do (name) ->
-    module.exports[name] = (args...) ->
-      checkAppIsReady()
-      binding[name](args...)