ash/accessibility/accessibility_panel_layout_manager.cc

// Copyright 2018 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/accessibility/accessibility_panel_layout_manager.h"

#include "ash/root_window_controller.h"
#include "ash/shelf/shelf.h"
#include "ash/shell.h"
#include "base/logging.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/wm/core/window_util.h"
#include "ui/wm/public/activation_client.h"

namespace ash {

AccessibilityPanelLayoutManager::AccessibilityPanelLayoutManager() {
  display::Screen::GetScreen()->AddObserver(this);
  Shell::Get()->activation_client()->AddObserver(this);
  Shell::Get()->AddShellObserver(this);
}

AccessibilityPanelLayoutManager::~AccessibilityPanelLayoutManager() {
  Shell::Get()->RemoveShellObserver(this);
  Shell::Get()->activation_client()->RemoveObserver(this);
  display::Screen::GetScreen()->RemoveObserver(this);
}

void AccessibilityPanelLayoutManager::SetPanelFullscreen(bool fullscreen) {
  panel_fullscreen_ = fullscreen;
  UpdateWindowBounds();
}

void AccessibilityPanelLayoutManager::OnWindowAddedToLayout(
    aura::Window* child) {
  panel_window_ = child;
  // Defer setting the window bounds until the extension is loaded and Chrome
  // shows the widget.
}

void AccessibilityPanelLayoutManager::OnWindowRemovedFromLayout(
    aura::Window* child) {
  // NOTE: In browser_tests a second ChromeVoxPanel can be created while the
  // first one is closing due to races between loading the extension and
  // closing the widget. We only track the latest panel.
  if (child == panel_window_)
    panel_window_ = nullptr;
  UpdateWorkArea();
}

void AccessibilityPanelLayoutManager::OnChildWindowVisibilityChanged(
    aura::Window* child,
    bool visible) {
  if (child == panel_window_ && visible) {
    UpdateWindowBounds();
    UpdateWorkArea();
  }
}

void AccessibilityPanelLayoutManager::SetChildBounds(
    aura::Window* child,
    const gfx::Rect& requested_bounds) {
  SetChildBoundsDirect(child, requested_bounds);
}

void AccessibilityPanelLayoutManager::OnDisplayMetricsChanged(
    const display::Display& display,
    uint32_t changed_metrics) {
  UpdateWindowBounds();
}

void AccessibilityPanelLayoutManager::OnWindowActivated(
    ActivationReason reason,
    aura::Window* gained_active,
    aura::Window* lost_active) {
  UpdateWindowBounds();
}

void AccessibilityPanelLayoutManager::OnFullscreenStateChanged(
    bool is_fullscreen,
    aura::Window* root_window) {
  UpdateWindowBounds();
}

void AccessibilityPanelLayoutManager::UpdateWindowBounds() {
  if (!panel_window_)
    return;

  aura::Window* root_window = panel_window_->GetRootWindow();
  RootWindowController* root_controller =
      RootWindowController::ForWindow(root_window);

  // By default the panel sits at the top of the screen.
  DCHECK(panel_window_->bounds().origin().IsOrigin());
  gfx::Rect bounds(0, 0, root_window->bounds().width(), kPanelHeight);

  // The panel can make itself fill the screen (including covering the shelf).
  if (panel_fullscreen_)
    bounds.set_height(root_window->bounds().height());

  // If a fullscreen browser window is open, give the panel a height of 0
  // unless it's active.
  if (root_controller->GetWindowForFullscreenMode() &&
      !::wm::IsActiveWindow(panel_window_)) {
    bounds.set_height(0);
  }

  // Make sure the ChromeVox panel is always below the Docked Magnifier viewport
  // so it shows up and gets magnified.
  bounds.Offset(0, root_controller->shelf()->GetDockedMagnifierHeight());

  panel_window_->SetBounds(bounds);
}

void AccessibilityPanelLayoutManager::UpdateWorkArea() {
  Shell::GetPrimaryRootWindowController()->shelf()->SetAccessibilityPanelHeight(
      panel_window_ ? panel_window_->bounds().height() : 0);
}

}  // namespace ash