Factor out AppLifetimeMonitor.

AppLifetimeMonitor listens to extension host notifications and observes
ShellWindowRegistry. It sends out notifications when:
- an app starts
- the first shell window opens
- the last shell window closes
- the app stops

BUG=

Review URL: https://chromiumcodereview.appspot.com/16412002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@204487 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 82 insertions, 0 deletions

diff --git a/apps/app_lifetime_monitor.h b/apps/app_lifetime_monitor.h
new file mode 100644
index 0000000..00c1ccc
--- /dev/null
+++ b/apps/app_lifetime_monitor.h
@@ -0,0 +1,82 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef APPS_APP_LIFETIME_MONITOR_H_
+#define APPS_APP_LIFETIME_MONITOR_H_
+
+#include <string>
+#include <vector>
+
+#include "base/observer_list.h"
+#include "chrome/browser/extensions/shell_window_registry.h"
+#include "components/browser_context_keyed_service/browser_context_keyed_service.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+namespace extensions {
+class Extension;
+}
+
+class Profile;
+
+namespace apps {
+
+// Observes startup of apps and their windows and notifies observers of these
+// events.
+class AppLifetimeMonitor : public BrowserContextKeyedService,
+                           public content::NotificationObserver,
+                           public extensions::ShellWindowRegistry::Observer {
+ public:
+  class Observer {
+   public:
+    // Called when the app starts running.
+    virtual void OnAppStart(Profile* profile, const std::string& app_id) = 0;
+    // Called when the app becomes active to the user, i.e. it opens a window.
+    virtual void OnAppActivated(Profile* profile,
+                                const std::string& app_id) = 0;
+    // Called when the app becomes inactive to the user.
+    virtual void OnAppDeactivated(Profile* profile,
+                                  const std::string& app_id) = 0;
+    // Called when the app stops running.
+    virtual void OnAppStop(Profile* profile, const std::string& app_id) = 0;
+
+   protected:
+    virtual ~Observer() {}
+  };
+
+  explicit AppLifetimeMonitor(Profile* profile);
+  virtual ~AppLifetimeMonitor();
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+ private:
+  // content::NotificationObserver overrides:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  // extensions::ShellWindowRegistry::Observer overrides:
+  virtual void OnShellWindowAdded(ShellWindow* shell_window) OVERRIDE;
+  virtual void OnShellWindowIconChanged(ShellWindow* shell_window) OVERRIDE;
+  virtual void OnShellWindowRemoved(ShellWindow* shell_window) OVERRIDE;
+
+  // BrowserContextKeyedService overrides:
+  virtual void Shutdown() OVERRIDE;
+
+  void NotifyAppStart(const std::string& app_id);
+  void NotifyAppActivated(const std::string& app_id);
+  void NotifyAppDeactivated(const std::string& app_id);
+  void NotifyAppStop(const std::string& app_id);
+
+  content::NotificationRegistrar registrar_;
+  Profile* profile_;
+  ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(AppLifetimeMonitor);
+};
+
+}  // namespace apps
+
+#endif  // APPS_APP_LIFETIME_MONITOR_H_