Native Android accessibility.

content/browser/accessibility/browser_accessibility_manager_android.cc

 // Copyright 2013 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 "content/browser/accessibility/browser_accessibility_manager_android.h"
 
 #include <cmath>
 
+#include "base/android/build_info.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "content/browser/accessibility/browser_accessibility_android.h"
 #include "content/common/accessibility_messages.h"
+#include "jni/BrowserAccessibilityManager_jni.h"
 
 using base::android::AttachCurrentThread;
 using base::android::ScopedJavaLocalRef;
 
 namespace {
 
+const int kJellyBeanSdkLevel = 16;
+
+// These are enums from android.view.accessibility.AccessibilityEvent in Java:
+enum {
+  ANDROID_ACCESSIBILITY_EVENT_TYPE_VIEW_TEXT_CHANGED = 16,
+  ANDROID_ACCESSIBILITY_EVENT_TYPE_VIEW_TEXT_SELECTION_CHANGED = 8192
+};
+
 // Restricts |val| to the range [min, max].
 int Clamp(int val, int min, int max) {
   return std::min(std::max(val, min), max);
 }
 
 }  // anonymous namespace
 
 namespace content {
 
 namespace aria_strings {
@@ skipping 12 matching lines @@
 
 BrowserAccessibilityManagerAndroid::BrowserAccessibilityManagerAndroid(
     ScopedJavaLocalRef<jobject> content_view_core,
     const AccessibilityNodeData& src,
     BrowserAccessibilityDelegate* delegate,
     BrowserAccessibilityFactory* factory)
     : BrowserAccessibilityManager(src, delegate, factory) {
   if (content_view_core.is_null())
     return;
 
-  // TODO(aboxhall): set up Java references
+  if (base::android::BuildInfo::GetInstance()->sdk_int() < kJellyBeanSdkLevel)

[joth, 2013/06/21 23:35:39]

seems unfortunate to duplicate the check here as well as
ContentViewCore.setNativeAccessibilityState(). I can't get a picture how the
callstack looks that results in us getting here, but if there is some way we can
either pass in this setting as a param, or fetch out the manager.IsAvailable() 
state back to java it would at least put the logic in one place.

[dmazzoni, 2013/06/22 06:53:47]

Actually the Java logic does take care of it...this is actually just to allow
the accessibility content_browsertests to run on ICS rather than crash. :)
I'll add a comment.

+    return;
+
+  JNIEnv* env = AttachCurrentThread();
+  java_ref_ = JavaObjectWeakGlobalRef(
+      env, Java_BrowserAccessibilityManager_create(
+          env, reinterpret_cast<jint>(this), content_view_core.obj()).obj());
 }
 
 BrowserAccessibilityManagerAndroid::~BrowserAccessibilityManagerAndroid() {
-  JNIEnv* env = base::android::AttachCurrentThread();
+  JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
   if (obj.is_null())
     return;
 
-  // TODO(aboxhall): tear down Java references
+  Java_BrowserAccessibilityManager_onNativeObjectDestroyed(env, obj.obj());
 }
 
 // static
 AccessibilityNodeData BrowserAccessibilityManagerAndroid::GetEmptyDocument() {
   AccessibilityNodeData empty_document;
   empty_document.id = 0;
   empty_document.role = AccessibilityNodeData::ROLE_ROOT_WEB_AREA;
   empty_document.state = 1 << AccessibilityNodeData::STATE_READONLY;
   return empty_document;
 }
 
 void BrowserAccessibilityManagerAndroid::NotifyAccessibilityEvent(
     int type,
     BrowserAccessibility* node) {
-  JNIEnv* env = base::android::AttachCurrentThread();
+  JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
   if (obj.is_null())
     return;
 
-  // TODO(aboxhall): call into appropriate Java method for each type of
-  // notification
+  switch (type) {
+    case AccessibilityNotificationLoadComplete:
+      Java_BrowserAccessibilityManager_handlePageLoaded(
+          env, obj.obj(), focus_->renderer_id());
+      break;
+    case AccessibilityNotificationFocusChanged:
+      Java_BrowserAccessibilityManager_handleFocusChanged(
+          env, obj.obj(), node->renderer_id());
+      break;
+    case AccessibilityNotificationCheckStateChanged:
+      Java_BrowserAccessibilityManager_handleCheckStateChanged(
+          env, obj.obj(), node->renderer_id());
+      break;
+    case AccessibilityNotificationScrolledToAnchor:
+      Java_BrowserAccessibilityManager_handleScrolledToAnchor(
+          env, obj.obj(), node->renderer_id());
+      break;
+    case AccessibilityNotificationAlert:
+      // An alert is a special case of live region. Fall through to the
+      // next case to handle it.
+    case AccessibilityNotificationObjectShow: {
+      // This event is fired when an object appears in a live region.
+      // Speak its text.
+      BrowserAccessibilityAndroid* android_node =
+          static_cast<BrowserAccessibilityAndroid*>(node);
+      Java_BrowserAccessibilityManager_announceLiveRegionText(
+          env, obj.obj(),
+          base::android::ConvertUTF16ToJavaString(
+              env, android_node->GetText()).obj());
+      break;
+    }
+    case AccessibilityNotificationSelectedTextChanged:
+      Java_BrowserAccessibilityManager_handleTextSelectionChanged(
+          env, obj.obj(), node->renderer_id());
+      break;
+    case AccessibilityNotificationChildrenChanged:
+    case AccessibilityNotificationTextChanged:
+    case AccessibilityNotificationValueChanged:
+      if (node->IsEditableText()) {
+        Java_BrowserAccessibilityManager_handleEditableTextChanged(
+            env, obj.obj(), node->renderer_id());
+      } else {
+        Java_BrowserAccessibilityManager_handleContentChanged(
+            env, obj.obj(), node->renderer_id());
+      }
+      break;
+    default:
+      // There are some notifications that aren't meaningful on Android.
+      // It's okay to skip them.
+      break;
+  }
 }
 
 jint BrowserAccessibilityManagerAndroid::GetRootId(JNIEnv* env, jobject obj) {
   return static_cast<jint>(root_->renderer_id());
 }
 
 jint BrowserAccessibilityManagerAndroid::HitTest(
     JNIEnv* env, jobject obj, jint x, jint y) {
   BrowserAccessibilityAndroid* result =
       static_cast<BrowserAccessibilityAndroid*>(
           root_->BrowserAccessibilityForPoint(gfx::Point(x, y)));
 
   if (!result)
     return root_->renderer_id();
 
   if (result->IsFocusable())
     return result->renderer_id();
 
   // Examine the children of |result| to find the nearest accessibility focus
   // candidate
   BrowserAccessibility* nearest_node = FuzzyHitTest(x, y, result);
   if (nearest_node)
     return nearest_node->renderer_id();
 
   return root_->renderer_id();
 }
 
+jboolean BrowserAccessibilityManagerAndroid::PopulateAccessibilityNodeInfo(
+    JNIEnv* env, jobject obj, jobject info, jint id) {
+  BrowserAccessibilityAndroid* node = static_cast<BrowserAccessibilityAndroid*>(
+      GetFromRendererID(id));
+  if (!node)
+    return false;
+
+  if (node->parent()) {
+    Java_BrowserAccessibilityManager_setAccessibilityNodeInfoParent(
+        env, obj, info, node->parent()->renderer_id());
+  }
+  if (!node->IsLeaf()) {
+    for (unsigned i = 0; i < node->child_count(); ++i) {
+      Java_BrowserAccessibilityManager_addAccessibilityNodeInfoChild(
+          env, obj, info, node->children()[i]->renderer_id());
+    }
+  }
+  Java_BrowserAccessibilityManager_setAccessibilityNodeInfoBooleanAttributes(
+      env, obj, info,
+      id,
+      node->IsCheckable(),
+      node->IsChecked(),
+      node->IsClickable(),
+      node->IsEnabled(),
+      node->IsFocusable(),
+      node->IsFocused(),
+      node->IsPassword(),
+      node->IsScrollable(),
+      node->IsSelected(),
+      node->IsVisibleToUser());
+  Java_BrowserAccessibilityManager_setAccessibilityNodeInfoStringAttributes(
+      env, obj, info,
+      base::android::ConvertUTF8ToJavaString(env, node->GetClassName()).obj(),
+      base::android::ConvertUTF16ToJavaString(env, node->GetText()).obj());
+
+  gfx::Rect absolute_rect = node->GetLocalBoundsRect();
+  gfx::Rect parent_relative_rect = absolute_rect;
+  if (node->parent()) {
+    gfx::Rect parent_rect = node->parent()->GetLocalBoundsRect();
+    parent_relative_rect.Offset(-parent_rect.OffsetFromOrigin());
+  }
+  bool is_root = node->parent() == NULL;
+  Java_BrowserAccessibilityManager_setAccessibilityNodeInfoLocation(
+      env, obj, info,
+      absolute_rect.x(), absolute_rect.y(),
+      parent_relative_rect.x(), parent_relative_rect.y(),
+      absolute_rect.width(), absolute_rect.height(),
+      is_root);
+
+  return true;
+}
+
+jboolean BrowserAccessibilityManagerAndroid::PopulateAccessibilityEvent(
+    JNIEnv* env, jobject obj, jobject event, jint id, jint event_type) {
+  BrowserAccessibilityAndroid* node = static_cast<BrowserAccessibilityAndroid*>(
+      GetFromRendererID(id));
+  if (!node)
+    return false;
+
+  Java_BrowserAccessibilityManager_setAccessibilityEventBooleanAttributes(
+      env, obj, event,
+      node->IsChecked(),
+      node->IsEnabled(),
+      node->IsPassword(),
+      node->IsScrollable());
+  Java_BrowserAccessibilityManager_setAccessibilityEventClassName(
+      env, obj, event,
+      base::android::ConvertUTF8ToJavaString(env, node->GetClassName()).obj());
+  Java_BrowserAccessibilityManager_setAccessibilityEventListAttributes(
+      env, obj, event,
+      node->GetItemIndex(),
+      node->GetItemCount());
+  Java_BrowserAccessibilityManager_setAccessibilityEventScrollAttributes(
+      env, obj, event,
+      node->GetScrollX(),
+      node->GetScrollY(),
+      node->GetMaxScrollX(),
+      node->GetMaxScrollY());
+
+  switch (event_type) {
+    case ANDROID_ACCESSIBILITY_EVENT_TYPE_VIEW_TEXT_CHANGED:
+      Java_BrowserAccessibilityManager_setAccessibilityEventTextChangedAttrs(
+          env, obj, event,
+          node->GetTextChangeFromIndex(),
+          node->GetTextChangeAddedCount(),
+          node->GetTextChangeRemovedCount(),
+          base::android::ConvertUTF16ToJavaString(
+              env, node->GetTextChangeBeforeText()).obj(),
+          base::android::ConvertUTF16ToJavaString(env, node->GetText()).obj());
+      break;
+    case ANDROID_ACCESSIBILITY_EVENT_TYPE_VIEW_TEXT_SELECTION_CHANGED:
+      Java_BrowserAccessibilityManager_setAccessibilityEventSelectionAttrs(
+          env, obj, event,
+          node->GetSelectionStart(),
+          node->GetSelectionEnd(),
+          node->GetEditableTextLength(),
+          base::android::ConvertUTF16ToJavaString(env, node->GetText()).obj());
+      break;
+    default:
+      break;
+  }
+
+  return true;
+}
+
+void BrowserAccessibilityManagerAndroid::Click(
+    JNIEnv* env, jobject obj, jint id) {
+  BrowserAccessibility* node = GetFromRendererID(id);
+  if (node)
+    DoDefaultAction(*node);
+}
+
+void BrowserAccessibilityManagerAndroid::Focus(
+    JNIEnv* env, jobject obj, jint id) {
+  BrowserAccessibility* node = GetFromRendererID(id);
+  if (node)
+    SetFocus(node, true);
+}
+
+void BrowserAccessibilityManagerAndroid::Blur(JNIEnv* env, jobject obj) {
+  SetFocus(root_, true);
+}
+
 BrowserAccessibility* BrowserAccessibilityManagerAndroid::FuzzyHitTest(
     int x, int y, BrowserAccessibility* start_node) {
   BrowserAccessibility* nearest_node = NULL;
   int min_distance = INT_MAX;
   FuzzyHitTestImpl(x, y, start_node, &nearest_node, &min_distance);
   return nearest_node;
 }
 
 // static
 void BrowserAccessibilityManagerAndroid::FuzzyHitTestImpl(
     int x, int y, BrowserAccessibility* start_node,
     BrowserAccessibility** nearest_candidate, int* nearest_distance) {
   BrowserAccessibilityAndroid* node =
       static_cast<BrowserAccessibilityAndroid*>(start_node);
   int distance = CalculateDistanceSquared(x, y, node);
 
   if (node->IsFocusable()) {
     if (distance < *nearest_distance) {
       *nearest_candidate = node;
       *nearest_distance = distance;
     }
     // Don't examine any more children of focusable node
     // TODO(aboxhall): what about focusable children?
     return;
   }
 
-  if (!node->ComputeName().empty()) {
+  if (!node->GetText().empty()) {
     if (distance < *nearest_distance) {
       *nearest_candidate = node;
       *nearest_distance = distance;
     }
     return;
   }
 
   if (!node->IsLeaf()) {
     for (uint32 i = 0; i < node->child_count(); i++) {
       BrowserAccessibility* child = node->GetChild(i);
       FuzzyHitTestImpl(x, y, child, nearest_candidate, nearest_distance);
     }
   }
 }
 
 // static
 int BrowserAccessibilityManagerAndroid::CalculateDistanceSquared(
     int x, int y, BrowserAccessibility* node) {
   gfx::Rect node_bounds = node->GetLocalBoundsRect();
   int nearest_x = Clamp(x, node_bounds.x(), node_bounds.right());
   int nearest_y = Clamp(y, node_bounds.y(), node_bounds.bottom());
   int dx = std::abs(x - nearest_x);
   int dy = std::abs(y - nearest_y);
   return dx * dx + dy * dy;
 }
 
-jint BrowserAccessibilityManagerAndroid::GetNativeNodeById(
-    JNIEnv* env, jobject obj, jint id) {
-  return reinterpret_cast<jint>(GetFromRendererID(id));
-}
+void BrowserAccessibilityManagerAndroid::NotifyRootChanged() {
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
+  if (obj.is_null())
+    return;
 
-void BrowserAccessibilityManagerAndroid::NotifyRootChanged() {
-  // TODO(aboxhall): non-stub implementation
+  Java_BrowserAccessibilityManager_handleNavigate(env, obj.obj());
 }
 
 bool
 BrowserAccessibilityManagerAndroid::UseRootScrollOffsetsWhenComputingBounds() {
   // The Java layer handles the root scroll offset.
   return false;
 }
 
 bool RegisterBrowserAccessibilityManager(JNIEnv* env) {
-  // TODO(aboxhall): non-stub implementation
-  return false;
+  return RegisterNativesImpl(env);
 }
 
 }  // namespace content