Athena: Adding basic resource management framework (un-/re-loading) of V2 applications

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 "athena/activity/public/activity_manager.h"
+#include "athena/content/app_activity_registry.h"
+#include "athena/content/public/app_content_delegate.h"
+#include "athena/content/public/app_registry.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/shell/browser/shell_app_window.h"
 #include "ui/views/controls/webview/webview.h"
+#include "ui/views/widget/widget.h"
 
 namespace athena {
 
 // TODO(mukai): specifies the same accelerators of WebActivity.
 AppActivity::AppActivity(extensions::ShellAppWindow* app_window)
     : app_window_(app_window),
       web_view_(NULL),
-      current_state_(ACTIVITY_UNLOADED) {
-  DCHECK(app_window_);
+      current_state_(ACTIVITY_UNLOADED),
+      app_activity_registry_(NULL) {
 }
 
 AppActivity::~AppActivity() {
-  if (GetCurrentState() != ACTIVITY_UNLOADED)
-    SetCurrentState(ACTIVITY_UNLOADED);
+  // If this activity is registered, we unregister it now.
+  if (app_activity_registry_)
+    app_activity_registry_->UnregisterAppActivity(this);
 }
 
 ActivityViewModel* AppActivity::GetActivityViewModel() {
   return this;
 }
 
 void AppActivity::SetCurrentState(Activity::ActivityState state) {
+  ActivityState current_state = state;
+  // Remember the last requested state now so that a call to GetCurrentState()
+  // returns the new state.
+  current_state_ = state;
+
   switch (state) {
     case ACTIVITY_VISIBLE:
       // Fall through (for the moment).
     case ACTIVITY_INVISIBLE:
       // 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.
+      // Note: A reload from the unloaded state will be performed through the
+      // |AppActivityProxy| object and no further action isn't necessary here.
       break;
     case ACTIVITY_BACKGROUND_LOW_PRIORITY:
-      DCHECK(ACTIVITY_VISIBLE == current_state_ ||
-             ACTIVITY_INVISIBLE == current_state_);
+      DCHECK(ACTIVITY_VISIBLE == current_state ||
+             ACTIVITY_INVISIBLE == current_state);
       // TODO(skuhne): Do this.
       break;
     case ACTIVITY_PERSISTENT:
-      DCHECK_EQ(ACTIVITY_BACKGROUND_LOW_PRIORITY, current_state_);
+      DCHECK_EQ(ACTIVITY_BACKGROUND_LOW_PRIORITY, current_state);
       // TODO(skuhne): Do this.
       break;
     case ACTIVITY_UNLOADED:
-      DCHECK_NE(ACTIVITY_UNLOADED, current_state_);
-      // TODO(skuhne): Find out how to evict an app from the extension system.
-      //      web_view_->EvictContent();
+      DCHECK_NE(ACTIVITY_UNLOADED, current_state);
+      // This will cause the application to shut down, close its windows and
+      // delete this object. Instead a |AppActivityProxy| will be created as
+      // place holder.
+      if (app_activity_registry_)
+        app_activity_registry_->Unload();
       break;
   }
-  // Remember the last requested state.
-  current_state_ = state;
 }
 
 Activity::ActivityState AppActivity::GetCurrentState() {
-  // TODO(skuhne): Check here also eviction status.
   if (!web_view_) {
     DCHECK_EQ(ACTIVITY_UNLOADED, current_state_);
     return ACTIVITY_UNLOADED;
   }
   // TODO(skuhne): This should be controlled by an observer and should not
   // reside here.
   if (IsVisible() && current_state_ != ACTIVITY_VISIBLE)
     SetCurrentState(ACTIVITY_VISIBLE);
   // Note: If the activity is not visible it does not necessarily mean that it
   // does not have GPU compositor resources (yet).
   return current_state_;
 }
 
 bool AppActivity::IsVisible() {
   return web_view_ && web_view_->IsDrawn();
 }
 
 Activity::ActivityMediaState AppActivity::GetMediaState() {
   // TODO(skuhne): The function GetTabMediaStateForContents(WebContents),
   // and the AudioStreamMonitor needs to be moved from Chrome into contents to
   // make it more modular and so that we can use it from here.
   return Activity::ACTIVITY_MEDIA_STATE_NONE;
 }
 
+aura::Window* AppActivity::GetWindow() {
+  return !web_view_ ? NULL : web_view_->GetWidget()->GetNativeWindow();
+}
+
 void AppActivity::Init() {
 }
 
 SkColor AppActivity::GetRepresentativeColor() const {
   // TODO(sad): Compute the color from the favicon.
   return SK_ColorGRAY;
 }
 
 base::string16 AppActivity::GetTitle() const {
   return web_view_->GetWebContents()->GetTitle();
@@ skipping 28 matching lines @@
 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);
 }
 
+void AppActivity::DidStartNavigationToPendingEntry(
+      const GURL& url,
+      content::NavigationController::ReloadType reload_type) {
+  if (!app_activity_registry_)
+    RegisterActivity();
+}
+
+// Register an |activity| with an application.
+// Note: This should only get called once for an |app_window| of the
+// |activity|.
+void AppActivity::RegisterActivity() {
+  if (app_activity_registry_)
+    return;
+  content::WebContents* web_contents = app_window_->GetAssociatedWebContents();
+  AppRegistry* app_registry = AppRegistry::Get();
+  // Get the application's registry.
+  app_activity_registry_ = app_registry->GetAppActivityRegistry(
+          app_registry->GetDelegate()->GetExtensionID(web_contents),
+          web_contents->GetBrowserContext());

[oshima, 2014/08/18 23:14:02]

looks like all information passed can be obtained from app_registry and
web_contents. How about the following instead?

app_registry->GetAppActivityRegistry(web_contents) ?

[Mr4D (OOO till 08-26), 2014/08/19 14:21:10]

This was done to allow unit tests to work. They can specify an app id and a
context of NULL.

[oshima, 2014/08/19 21:22:24]

Ok, I'm fine for now, but when we introduced the (real) content dependency to
athena, we can switch to use TestWebContents.

[Mr4D (OOO till 08-26), 2014/08/20 14:34:39]

Sure.

+  DCHECK(app_activity_registry_);
+  // Register the activity.
+  app_activity_registry_->RegisterAppActivity(this);
+}
+
 }  // namespace athena