Lock Rotation on user settings changes

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/accelerators/accelerator_controller.h"
 #include "ash/accelerators/accelerator_table.h"
 #include "ash/accelerometer/accelerometer_controller.h"
 #include "ash/ash_switches.h"
@@ skipping 127 matching lines @@
       have_seen_accelerometer_data_(false),
       in_set_screen_rotation_(false),
       user_rotation_(gfx::Display::ROTATE_0) {
   Shell::GetInstance()->accelerometer_controller()->AddObserver(this);
 }
 
 MaximizeModeController::~MaximizeModeController() {
   Shell::GetInstance()->accelerometer_controller()->RemoveObserver(this);
 }
 
+void MaximizeModeController::SetRotationLocked(bool rotation_locked) {
+  if (rotation_locked_ == rotation_locked)
+    return;
+  rotation_locked_ = rotation_locked;
+  FOR_EACH_OBSERVER(Observer, observers_,
+                    OnRotationLockChanged(rotation_locked_));
+}
+
+void MaximizeModeController::AddObserver(Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void MaximizeModeController::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
 bool MaximizeModeController::CanEnterMaximizeMode() {
   // If we have ever seen accelerometer data, then HandleHingeRotation may
   // trigger maximize mode at some point in the future.
   // The --enable-touch-view-testing switch can also mean that we may enter
   // maximize mode.
   return have_seen_accelerometer_data_ ||
          CommandLine::ForCurrentProcess()->HasSwitch(
              switches::kAshEnableTouchViewTesting);
 }
 
@@ skipping 12 matching lines @@
       std::abs(lid_magnitude - 1.0f) > kDeviationFromGravityThreshold) {
       return;
   }
 
   // Responding to the hinge rotation can change the maximize mode state which
   // affects screen rotation, so we handle hinge rotation first.
   HandleHingeRotation(base, lid);
   HandleScreenRotation(lid);
 }
 
+void MaximizeModeController::OnDisplayConfigurationChanged() {
+  if (rotation_locked_ || in_set_screen_rotation_)

[flackr, 2014/05/30 00:47:24]

If rotation is locked you should still track updates to the user_rotation_ which
you'll be exiting to.

[jonross, 2014/05/30 14:52:44]

Done.

[flackr, 2014/05/30 18:58:59]

Not exactly, if the rotation changes to current_rotation_ (which is still what
the accelerometer was reading when we locked the rotation), we won't record it
as the user_rotation_. If the rotation is locked we should just update
user_rotation_ to the new rotation.

[flackr, 2014/06/02 15:11:11]

Not changed yet?

[jonross, 2014/06/02 18:01:12]

Apparently this is listed in the Diff from Patch #2

+    return;
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  gfx::Display::Rotation user_rotation = display_manager->
+      GetDisplayInfo(gfx::Display::InternalDisplayId()).rotation();
+  if (user_rotation != current_rotation_) {
+    // A user may change other display configuration settings. When the user
+    // does change the rotation setting, then lock rotation to prevent the
+    // accelerometer from erasing their change.
+    SetRotationLocked(true);
+    user_rotation_ = user_rotation;
+  }
+}
+
 void MaximizeModeController::HandleHingeRotation(const gfx::Vector3dF& base,
                                                  const gfx::Vector3dF& lid) {
   static const gfx::Vector3dF hinge_vector(0.0f, 1.0f, 0.0f);
   bool maximize_mode_engaged =
       Shell::GetInstance()->IsMaximizeModeWindowManagerEnabled();
   // Ignore the component of acceleration parallel to the hinge for the purposes
   // of hinge angle calculation.
   gfx::Vector3dF base_flattened(base);
   gfx::Vector3dF lid_flattened(lid);
   base_flattened.set_y(0.0f);
@@ skipping 22 matching lines @@
   } else if (!maximize_mode_engaged &&
       angle > kEnterMaximizeModeAngle) {
     EnterMaximizeMode();
   }
 }
 
 void MaximizeModeController::HandleScreenRotation(const gfx::Vector3dF& lid) {
   bool maximize_mode_engaged =
       Shell::GetInstance()->IsMaximizeModeWindowManagerEnabled();
 
+  // TODO(jonross): track the updated rotation angle even when locked. So that
+  // when rotation lock is removed the accelerometer rotation can be applied
+  // without waiting for the next update.
   if (!maximize_mode_engaged || rotation_locked_)
     return;
 
   DisplayManager* display_manager =
       Shell::GetInstance()->display_manager();
   gfx::Display::Rotation current_rotation = display_manager->GetDisplayInfo(
       gfx::Display::InternalDisplayId()).rotation();
 
   // After determining maximize mode state, determine if the screen should
   // be rotated.
@@ skipping 42 matching lines @@
 
   if (new_rotation != current_rotation)
     SetDisplayRotation(display_manager, new_rotation);
 }
 
 void MaximizeModeController::SetDisplayRotation(
     DisplayManager* display_manager,
     gfx::Display::Rotation rotation) {
   base::AutoReset<bool> auto_in_set_screen_rotation(
       &in_set_screen_rotation_, true);
+  current_rotation_ = rotation;
   display_manager->SetDisplayRotation(gfx::Display::InternalDisplayId(),
                                       rotation);
 }
 
 void MaximizeModeController::EnterMaximizeMode() {
-  // TODO(jonross): Listen for display configuration changes. If the user
-  // causes a rotation change a rotation lock should be applied.
-  // https://crbug.com/369505
   DisplayManager* display_manager = Shell::GetInstance()->display_manager();
-  user_rotation_ = display_manager->
+  current_rotation_ = user_rotation_ = display_manager->
       GetDisplayInfo(gfx::Display::InternalDisplayId()).rotation();
   Shell::GetInstance()->EnableMaximizeModeWindowManager(true);
   event_blocker_.reset(new MaximizeModeEventBlocker);
 #if defined(OS_CHROMEOS)
   event_handler_.reset(new ScreenshotActionHandler);
 #endif
+  Shell::GetInstance()->display_controller()->AddObserver(this);
 }
 
 void MaximizeModeController::LeaveMaximizeMode() {
   DisplayManager* display_manager = Shell::GetInstance()->display_manager();
-  DisplayInfo info = display_manager->
-      GetDisplayInfo(gfx::Display::InternalDisplayId());
-  gfx::Display::Rotation current_rotation = info.rotation();
+  gfx::Display::Rotation current_rotation = display_manager->
+      GetDisplayInfo(gfx::Display::InternalDisplayId()).rotation();
   if (current_rotation != user_rotation_)
     SetDisplayRotation(display_manager, user_rotation_);
   rotation_locked_ = false;
   Shell::GetInstance()->EnableMaximizeModeWindowManager(false);
   event_blocker_.reset();
   event_handler_.reset();
+  Shell::GetInstance()->display_controller()->RemoveObserver(this);
 }
 
 }  // namespace ash