Additions to Activities to allow resource management

athena/content/app_activity.cc

 // Copyright 2014 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.
 
 #include "athena/content/app_activity.h"
 
 #include "apps/shell/browser/shell_app_window.h"
 #include "athena/activity/public/activity_manager.h"
 #include "content/public/browser/web_contents.h"
 #include "ui/views/controls/webview/webview.h"
 
 namespace athena {
 
 // TODO(mukai): specifies the same accelerators of WebActivity.
 AppActivity::AppActivity(apps::ShellAppWindow* app_window)
-    : app_window_(app_window), web_view_(NULL) {
+    : app_window_(app_window),
+      web_view_(NULL),
+      last_requested_state_(ACTIVITY_UNLOAD) {
   DCHECK(app_window_);
 }
 
 AppActivity::~AppActivity() {
+  if (GetCurrentState() != ACTIVITY_STATE_UNLOADED)
+    SetCurrentState(ACTIVITY_UNLOAD);
 }
 
 ActivityViewModel* AppActivity::GetActivityViewModel() {
   return this;
 }
 
+void AppActivity::SetCurrentState(Activity::ActivityStateTransition state) {
+  switch (state) {
+    case ACTIVITY_LOAD:
+      // By clearing the overview mode image we allow the content to be shown.
+      overview_mode_image_ = gfx::ImageSkia();
+// TODO(skuhne): Find out how to reload an app from the extension system.
+// If this does not work, the eviction needs to take place at a higher level.
+//      if (web_view_->IsContentEvicted()) {
+//        DCHECK_EQ(ACTIVITY_UNLOAD, last_requested_state_);
+//        web_view_->ReloadContent();
+//      }
+      break;
+    case ACTIVITY_DEEP_SLEEP_1:
+      DCHECK_EQ(ACTIVITY_LOAD, last_requested_state_);
+      // TODO(skuhne): Do this. As soon as the new resource management is
+      // agreed upon - or remove otherwise.
+      break;
+    case ACTIVITY_DEEP_SLEEP_2:
+      DCHECK_EQ(ACTIVITY_DEEP_SLEEP_1, last_requested_state_);
+      // TODO(skuhne): Do this. As soon as the new resource management is
+      // agreed upon - or remove otherwise.
+      break;
+    case ACTIVITY_UNLOAD:
+      DCHECK_NE(ACTIVITY_UNLOAD, last_requested_state_);
+// TODO(skuhne): Find out how to evict an app from the extension system.
+//      web_view_->EvictContent();
+      break;
+  }
+  // Remember the last requested state.
+  last_requested_state_ = state;
+}
+
+Activity::ActivityState AppActivity::GetCurrentState() {
+  if (!web_view_) {
+    DCHECK_EQ(ACTIVITY_UNLOAD, last_requested_state_);
+    return ACTIVITY_STATE_UNLOADED;
+  }
+
+  switch(last_requested_state_) {
+    case ACTIVITY_LOAD:
+      if (web_view_->IsDrawn())
+        return ACTIVITY_STATE_VISIBLE;
+      /*
+      // TODO(skuhne): AudioStreamMonitor is currently a part of Chrome and
+      // needs to be moved some levels up.
+        AudioStreamMonitor* const audio_stream_monitor =
+            AudioStreamMonitor::FromWebContents(contents);
+        if (audio_stream_monitor && audio_stream_monitor->WasRecentlyAudible())
+          return ACTIVITY_STATE_BACKGROUND_ACTIVE;
+      */
+      return ACTIVITY_STATE_HIDDEN;
+    case ACTIVITY_DEEP_SLEEP_1:
+      return ACTIVITY_STATE_DEEP_SLEEP_1;
+    case ACTIVITY_DEEP_SLEEP_2:
+      return ACTIVITY_STATE_DEEP_SLEEP_2;
+    case ACTIVITY_UNLOAD:
+      return ACTIVITY_STATE_UNLOADED;
+  }
+  return ACTIVITY_STATE_UNLOADED;
+}
+
 void AppActivity::Init() {
 }
 
 SkColor AppActivity::GetRepresentativeColor() {
   // TODO(sad): Compute the color from the favicon.
   return SK_ColorGRAY;
 }
 
 base::string16 AppActivity::GetTitle() {
   return web_view_->GetWebContents()->GetTitle();
 }
 
 views::View* AppActivity::GetContentsView() {
   if (!web_view_) {
     content::WebContents* web_contents =
         app_window_->GetAssociatedWebContents();
     web_view_ = new views::WebView(web_contents->GetBrowserContext());
     web_view_->SetWebContents(web_contents);
+    SetCurrentState(ACTIVITY_LOAD);
     Observe(web_contents);
+    overview_mode_image_ = gfx::ImageSkia();
   }
   return web_view_;
 }
 
+void AppActivity::CreateOverviewModeImage() {
+  // TODO(skuhne): Implement this!
+}
+
+gfx::ImageSkia AppActivity::GetOverviewModeImage() {
+  return overview_mode_image_;
+}
+
 void AppActivity::TitleWasSet(content::NavigationEntry* entry,
                               bool explicit_set) {
   ActivityManager::Get()->UpdateActivity(this);
 }
 
 void AppActivity::DidUpdateFaviconURL(
     const std::vector<content::FaviconURL>& candidates) {
   ActivityManager::Get()->UpdateActivity(this);
 }
 
 }  // namespace athena