blob: 295dc3fb57a0510f6c9088e6a2c1fa0da4d4e9d3 [file] [log] [blame]
// Copyright 2016 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 <stdint.h>
#include <memory>
#include <vector>
#include "base/observer_list.h"
#include "ui/display/display.h"
#include "ui/display/display_export.h"
namespace display {
class Display;
class DisplayList;
class DisplayObserver;
// See description in DisplayLock::SuspendObserverUpdates.
class DISPLAY_EXPORT DisplayListObserverLock {
friend class DisplayList;
explicit DisplayListObserverLock(DisplayList* display_list);
DisplayList* display_list_;
// Maintains an ordered list of Displays as well as operations to add, remove
// and update said list. Additionally maintains DisplayObservers and updates
// them as appropriate.
class DISPLAY_EXPORT DisplayList {
using Displays = std::vector<Display>;
enum class Type {
void AddObserver(DisplayObserver* observer);
void RemoveObserver(DisplayObserver* observer);
const Displays& displays() const { return displays_; }
Displays::const_iterator FindDisplayById(int64_t id) const;
Displays::const_iterator GetPrimaryDisplayIterator() const;
// Internally increments a counter that while non-zero results in observers
// not being called for any changes to the displays. It is assumed once
// callers release the last lock they call the observers appropriately.
std::unique_ptr<DisplayListObserverLock> SuspendObserverUpdates();
void AddOrUpdateDisplay(const Display& display, Type type);
// Updates the cached display based on This returns a bitmask
// of the changed values suitable for passing to
// DisplayObserver::OnDisplayMetricsChanged().
uint32_t UpdateDisplay(const Display& display);
// Updates the cached display based on Also updates the primary
// display if |type| indicates |display| is the primary display. See single
// argument version for description of return value.
uint32_t UpdateDisplay(const Display& display, Type type);
// Adds a new Display.
void AddDisplay(const Display& display, Type type);
// Removes the Display with the specified id.
void RemoveDisplay(int64_t id);
base::ObserverList<DisplayObserver>* observers() { return &observers_; }
friend class DisplayListObserverLock;
bool should_notify_observers() const {
return observer_suspend_lock_count_ == 0;
void IncrementObserverSuspendLockCount();
void DecrementObserverSuspendLockCount();
Type GetTypeByDisplayId(int64_t display_id) const;
Displays::iterator FindDisplayByIdInternal(int64_t id);
std::vector<Display> displays_;
int primary_display_index_ = -1;
base::ObserverList<DisplayObserver> observers_;
int observer_suspend_lock_count_ = 0;
} // namespace display