Suppressed screen rotation notifications triggeres by the accelerometer

ash/wm/maximize_mode/maximize_mode_controller.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 "ash/wm/maximize_mode/maximize_mode_controller.h"
 
 #include "ash/accelerometer/accelerometer_controller.h"
 #include "ash/display/display_manager.h"
 #include "ash/shell.h"
 #include "ash/wm/maximize_mode/maximize_mode_event_blocker.h"
 #include "ui/gfx/vector3d_f.h"
+#include "ui/message_center/message_center.h"
+#include "ui/message_center/notification_blocker.h"
 
 namespace ash {
 
 namespace {
 
 // The hinge angle at which to enter maximize mode.
 const float kEnterMaximizeModeAngle = 200.0f;
 
 // The angle at which to exit maximize mode, this is specifically less than the
 // angle to enter maximize mode to prevent rapid toggling when near the angle.
@@ skipping 27 matching lines @@
 // rotate to match it (i.e. 45.0f is no stickiness).
 const float kDisplayRotationStickyAngleDegrees = 60.0f;
 
 // The minimum acceleration in a direction required to trigger screen rotation.
 // This prevents rapid toggling of rotation when the device is near flat and
 // there is very little screen aligned force on it.
 const float kMinimumAccelerationScreenRotation = 0.3f;
 
 const float kRadiansToDegrees = 180.0f / 3.14159265f;
 
+// A message center notification blocker used to suppress screen rotation
+// events caused by accelerometer events

[flackr, 2014/05/05 21:12:12]

nit: Punctuation.

[bruthig, 2014/05/08 17:50:02]

Done.

+class ScopedNotificationBlocker
+    : public message_center::NotificationBlocker {
+ public:
+  ScopedNotificationBlocker();
+  virtual ~ScopedNotificationBlocker();
+
+ private:
+  // Overriden from message_center::NotificationBlocker.
+  virtual bool ShouldShowNotificationAsPopup(
+      const message_center::NotifierId& notifier_id) const OVERRIDE;
+
+// Overriden from message_center::NotificationBlocker.
+  virtual bool ShouldShowNotification(
+      const message_center::NotifierId& notifier_id) const OVERRIDE;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedNotificationBlocker);
+};
+
+ScopedNotificationBlocker::ScopedNotificationBlocker()
+    : message_center::NotificationBlocker(
+          message_center::MessageCenter::Get()) {
+  NotifyBlockingStateChanged();

[flackr, 2014/05/05 21:12:12]

Will this cause us to remove other currently active notifications?

[bruthig, 2014/05/08 17:50:02]

Nope

[bruthig, 2014/05/08 17:50:02]

Done.

+}
+
+ScopedNotificationBlocker::~ScopedNotificationBlocker() {
+}
+
+bool ScopedNotificationBlocker::ShouldShowNotificationAsPopup(
+    const message_center::NotifierId& notifier_id) const {
+  return false;
+}
+
+bool ScopedNotificationBlocker::ShouldShowNotification(
+    const message_center::NotifierId& notifier_id) const {
+  return false;
+}
+
 // Returns the angle between |base| and |other| in degrees.
 float AngleBetweenVectorsInDegrees(const gfx::Vector3dF& base,
                                  const gfx::Vector3dF& other) {
   return acos(gfx::DotProduct(base, other) /
               base.Length() / other.Length()) * kRadiansToDegrees;
 }
 
 // Returns the clockwise angle between |base| and |other| where |normal| is the
 // normal of the virtual surface to measure clockwise according to.
 float ClockwiseAngleBetweenVectorsInDegrees(const gfx::Vector3dF& base,
                                             const gfx::Vector3dF& other,
                                             const gfx::Vector3dF& normal) {
   float angle = AngleBetweenVectorsInDegrees(base, other);
   gfx::Vector3dF cross(base);
   cross.Cross(other);
   // If the dot product of this cross product is normal, it means that the
   // shortest angle between |base| and |other| was counterclockwise with respect
   // to the surface represented by |normal| and this angle must be reversed.
   if (gfx::DotProduct(cross, normal) > 0.0f)
     angle = 360.0f - angle;
   return angle;
 }
 
+// Sets the display's rotation.
+void SetDisplayRotation(DisplayManager* display_manager,
+                        int64 display_id,
+                        gfx::Display::Rotation rotation) {
+  // Suppress message centre notifications for screen rotations caused
+  // by accelerometer events because it should be obvious why the orientation
+  // changed.
+  ScopedNotificationBlocker notification_blocker;
+  display_manager->SetDisplayRotation(display_id, rotation);
+}
+
 }  // namespace
 
 MaximizeModeController::MaximizeModeController()
     : rotation_locked_(false) {
   Shell::GetInstance()->accelerometer_controller()->AddObserver(this);
 }
 
 MaximizeModeController::~MaximizeModeController() {
   Shell::GetInstance()->accelerometer_controller()->RemoveObserver(this);
 }
@@ skipping 70 matching lines @@
   // If maximize mode is not engaged, ensure the screen is not rotated and
   // do not rotate to match the current device orientation.
   if (!maximize_mode_engaged) {
     if (current_rotation != gfx::Display::ROTATE_0) {
       // TODO(flackr): Currently this will prevent setting a manual rotation on
       // the screen of a device with an accelerometer, this should only set it
       // back to ROTATE_0 if it was last set by the accelerometer.
       // Also, SetDisplayRotation will save the setting to the local store,
       // this should be stored in a way that we can distinguish what the
       // rotation was set by.
-      display_manager->SetDisplayRotation(gfx::Display::InternalDisplayId(),
-                                          gfx::Display::ROTATE_0);
+      SetDisplayRotation(display_manager,
+                         gfx::Display::InternalDisplayId(),
+                         gfx::Display::ROTATE_0);
     }
     rotation_locked_ = false;
     return;
   }
 
   if (rotation_locked_)
     return;
 
   // After determining maximize mode state, determine if the screen should
   // be rotated.
@@ skipping 37 matching lines @@
     new_rotation = gfx::Display::ROTATE_0;
   else if (angle < 180.0f)
     new_rotation = gfx::Display::ROTATE_270;
   else if (angle < 270.0f)
     new_rotation = gfx::Display::ROTATE_180;
 
   // When exiting maximize mode return rotation to 0. When entering, rotate to
   // match screen orientation.
   if (new_rotation == gfx::Display::ROTATE_0 ||
       maximize_mode_engaged) {
-    display_manager->SetDisplayRotation(gfx::Display::InternalDisplayId(),
-                                        new_rotation);
+    SetDisplayRotation(display_manager,
+                       gfx::Display::InternalDisplayId(),
+                       new_rotation);
   }
 }
 
 }  // namespace ash