ui/views/accessibility/native_view_accessibility_auralinux.cc

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/views/accessibility/native_view_accessibility_auralinux.h"
   6
   7 #include <algorithm>
   8 #include <vector>
   9
  10 #include "base/memory/singleton.h"
  11 #include "ui/accessibility/ax_enums.h"
  12 #include "ui/accessibility/ax_node_data.h"
  13 #include "ui/accessibility/platform/ax_platform_node_auralinux.h"
  14 #include "ui/accessibility/platform/ax_platform_node_delegate.h"
  15 #include "ui/gfx/native_widget_types.h"
  16 #include "ui/views/views_delegate.h"
  17 #include "ui/views/widget/widget.h"
  18 #include "ui/views/widget/widget_observer.h"
  19
  20 namespace views {
  21
  22 namespace {
  23
  24 // ATK requires that we have a single root "application" object that's the
  25 // owner of all other windows. This is a simple class that implements the
  26 // AXPlatformNodeDelegate interface so we can create such an application
  27 // object. Every time we create an accessibility object for a View, we add its
  28 // top-level widget to a vector so we can return the list of all top-level
  29 // windows as children of this application object.
  30 class AuraLinuxApplication
  31     : public ui::AXPlatformNodeDelegate,
  32       public WidgetObserver {
  33  public:
  34   // Get the single instance of this class.
  35   static AuraLinuxApplication* GetInstance() {
  36     return Singleton<AuraLinuxApplication>::get();
  37   }
  38
  39   // Called every time we create a new accessibility on a View.
  40   // Add the top-level widget to our registry so that we can enumerate all
  41   // top-level widgets.
  42   void RegisterWidget(Widget* widget) {
  43     if (!widget)
  44       return;
  45
  46     widget = widget->GetTopLevelWidget();
  47     if (std::find(widgets_.begin(), widgets_.end(), widget) != widgets_.end())
  48       return;
  49
  50     widgets_.push_back(widget);
  51     widget->AddObserver(this);
  52   }
  53
  54   gfx::NativeViewAccessible GetNativeViewAccessible() {
  55     return platform_node_->GetNativeViewAccessible();
  56   }
  57
  58   //
  59   // WidgetObserver overrides.
  60   //
  61
  62   void OnWidgetDestroying(Widget* widget) override {
  63     auto iter = std::find(widgets_.begin(), widgets_.end(), widget);
  64     if (iter != widgets_.end())
  65       widgets_.erase(iter);
  66   }
  67
  68   //
  69   // ui::AXPlatformNodeDelegate overrides.
  70   //
  71
  72   const ui::AXNodeData& GetData() override {
  73     return data_;
  74   }
  75
  76   gfx::NativeViewAccessible GetParent() override {
  77     return nullptr;
  78   }
  79
  80   int GetChildCount() override {
  81     return static_cast<int>(widgets_.size());
  82   }
  83
  84   gfx::NativeViewAccessible ChildAtIndex(int index) override {
  85     if (index < 0 || index >= GetChildCount())
  86       return nullptr;
  87
  88     Widget* widget = widgets_[index];
  89     CHECK(widget);
  90     return widget->GetRootView()->GetNativeViewAccessible();
  91   }
  92
  93   gfx::Vector2d GetGlobalCoordinateOffset() override {
  94     return gfx::Vector2d();
  95   }
  96
  97   gfx::NativeViewAccessible HitTestSync(int x, int y) override {
  98     return nullptr;
  99   }
 100
 101   gfx::NativeViewAccessible GetFocus() override {
 102     return nullptr;
 103   }
 104
 105   gfx::AcceleratedWidget GetTargetForNativeAccessibilityEvent() override {
 106     return gfx::kNullAcceleratedWidget;
 107   }
 108
 109   void DoDefaultAction() override {
 110   }
 111
 112   bool SetStringValue(const base::string16& new_value) override {
 113     return false;
 114   }
 115
 116  private:
 117   friend struct DefaultSingletonTraits<AuraLinuxApplication>;
 118
 119   AuraLinuxApplication()
 120       : platform_node_(ui::AXPlatformNode::Create(this)) {
 121     data_.role = ui::AX_ROLE_APPLICATION;
 122     if (ViewsDelegate::GetInstance()) {
 123       data_.AddStringAttribute(
 124           ui::AX_ATTR_NAME,
 125           ViewsDelegate::GetInstance()->GetApplicationName());
 126     }
 127     ui::AXPlatformNodeAuraLinux::SetApplication(platform_node_);
 128     if (ViewsDelegate::GetInstance()) {
 129       // This should be on the a blocking pool thread so that we can open
 130       // libatk-bridge.so without blocking this thread.
 131       scoped_refptr<base::TaskRunner> init_task_runner =
 132           ViewsDelegate::GetInstance()->GetBlockingPoolTaskRunner();
 133       if (init_task_runner)
 134         ui::AXPlatformNodeAuraLinux::StaticInitialize(init_task_runner);
 135     }
 136   }
 137
 138   ~AuraLinuxApplication() override {
 139     platform_node_->Destroy();
 140     platform_node_ = nullptr;
 141   }
 142
 143   ui::AXPlatformNode* platform_node_;
 144   ui::AXNodeData data_;
 145   std::vector<Widget*> widgets_;
 146
 147   DISALLOW_COPY_AND_ASSIGN(AuraLinuxApplication);
 148 };
 149
 150 }  // namespace
 151
 152 // static
 153 NativeViewAccessibility* NativeViewAccessibility::Create(View* view) {
 154   AuraLinuxApplication::GetInstance()->RegisterWidget(view->GetWidget());
 155   return new NativeViewAccessibilityAuraLinux(view);
 156 }
 157
 158 NativeViewAccessibilityAuraLinux::NativeViewAccessibilityAuraLinux(View* view)
 159     : NativeViewAccessibility(view) {
 160 }
 161
 162 NativeViewAccessibilityAuraLinux::~NativeViewAccessibilityAuraLinux() {
 163 }
 164
 165 gfx::NativeViewAccessible NativeViewAccessibilityAuraLinux::GetParent() {
 166   gfx::NativeViewAccessible parent = NativeViewAccessibility::GetParent();
 167   if (!parent)
 168     parent = AuraLinuxApplication::GetInstance()->GetNativeViewAccessible();
 169   return parent;
 170 }
 171
 172 }  // namespace views