gecko-dev/dom/base/WindowOrientationObserver.cpp

58 lines
1.8 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "WindowOrientationObserver.h"
#include "nsGlobalWindow.h"
#include "mozilla/Hal.h"
using namespace mozilla::dom;
/**
* This class is used by nsGlobalWindow to implement window.orientation
* and window.onorientationchange. This class is defined in its own file
* because Hal.h pulls in windows.h and can't be included from
* nsGlobalWindow.cpp
*/
WindowOrientationObserver::WindowOrientationObserver(
nsGlobalWindow* aGlobalWindow)
: mWindow(aGlobalWindow)
{
MOZ_ASSERT(aGlobalWindow && aGlobalWindow->IsInnerWindow());
hal::RegisterScreenConfigurationObserver(this);
hal::ScreenConfiguration config;
hal::GetCurrentScreenConfiguration(&config);
mAngle = config.angle();
}
WindowOrientationObserver::~WindowOrientationObserver()
{
hal::UnregisterScreenConfigurationObserver(this);
}
void
WindowOrientationObserver::Notify(
const mozilla::hal::ScreenConfiguration& aConfiguration)
{
uint16_t currentAngle = aConfiguration.angle();
if (mAngle != currentAngle && mWindow->AsInner()->IsCurrentInnerWindow()) {
mAngle = currentAngle;
mWindow->GetOuterWindow()->DispatchCustomEvent(NS_LITERAL_STRING("orientationchange"));
}
}
/* static */ int16_t
WindowOrientationObserver::OrientationAngle()
{
hal::ScreenConfiguration config;
hal::GetCurrentScreenConfiguration(&config);
int16_t angle = static_cast<int16_t>(config.angle());
// config.angle() returns 0, 90, 180 or 270.
// window.orientation returns -90, 0, 90 or 180.
return angle <= 180 ? angle : angle - 360;
}