Content side of changes to enable native accessibility on android.

This code has been written collaboratively by dmazzoni and aboxhall; see https://codereview.chromium.org/15741009/ for the first-pass review on all code changes.

BUG=242953
TBR=piman

Review URL: https://chromiumcodereview.appspot.com/16661006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@206193 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 85 insertions, 0 deletions

diff --git a/content/browser/accessibility/browser_accessibility_manager_android.h b/content/browser/accessibility/browser_accessibility_manager_android.h
new file mode 100644
index 0000000..0ca04e5
--- /dev/null
+++ b/content/browser/accessibility/browser_accessibility_manager_android.h
@@ -0,0 +1,85 @@
+// 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.
+
+#ifndef CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_ANDROID_H_
+#define CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_ANDROID_H_
+
+#include "base/android/scoped_java_ref.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
+#include "content/browser/android/content_view_core_impl.h"
+
+namespace content {
+
+namespace aria_strings {
+  extern const char kAriaLivePolite[];
+  extern const char kAriaLiveAssertive[];
+}
+
+class CONTENT_EXPORT BrowserAccessibilityManagerAndroid
+    : public BrowserAccessibilityManager {
+ public:
+  BrowserAccessibilityManagerAndroid(
+      base::android::ScopedJavaLocalRef<jobject> content_view_core,
+      const AccessibilityNodeData& src,
+      BrowserAccessibilityDelegate* delegate,
+      BrowserAccessibilityFactory* factory = new BrowserAccessibilityFactory());
+
+  virtual ~BrowserAccessibilityManagerAndroid();
+
+  static AccessibilityNodeData GetEmptyDocument();
+
+  // Implementation of BrowserAccessibilityManager.
+  virtual void NotifyAccessibilityEvent(int type,
+                                        BrowserAccessibility* node) OVERRIDE;
+
+  // --------------------------------------------------------------------------
+  // Methods called from Java via JNI
+  // --------------------------------------------------------------------------
+
+  // Tree methods.
+  jint GetRootId(JNIEnv* env, jobject obj);
+  jint HitTest(JNIEnv* env, jobject obj, jint x, jint y);
+
+  // Gets a temporary pointer to a specific node, only valid in this scope.
+  // May return 0 if that node id is no longer valid.
+  jint GetNativeNodeById(JNIEnv* env, jobject obj, jint id);
+
+ protected:
+  virtual void NotifyRootChanged() OVERRIDE;
+
+  virtual bool UseRootScrollOffsetsWhenComputingBounds() OVERRIDE;
+
+ private:
+  // This gives BrowserAccessibilityManager::Create access to the class
+  // constructor.
+  friend class BrowserAccessibilityManager;
+
+  // A weak reference to the Java BrowserAccessibilityManager object.
+  // This avoids adding another reference to BrowserAccessibilityManager and
+  // preventing garbage collection.
+  // Premature garbage collection is prevented by the long-lived reference in
+  // ContentViewCore.
+  JavaObjectWeakGlobalRef java_ref_;
+
+  // Searches through the children of start_node to find the nearest
+  // accessibility focus candidate for a touch which has not landed directly on
+  // an accessibility focus candidate.
+  BrowserAccessibility* FuzzyHitTest(
+      int x, int y, BrowserAccessibility* start_node);
+
+  static void FuzzyHitTestImpl(int x, int y, BrowserAccessibility* start_node,
+      BrowserAccessibility** nearest_candidate, int* min_distance);
+
+  // Calculates the distance from the point (x, y) to the nearest point on the
+  // edge of |node|.
+  static int CalculateDistanceSquared(int x, int y, BrowserAccessibility* node);
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManagerAndroid);
+};
+
+bool RegisterBrowserAccessibilityManager(JNIEnv* env);
+
+}
+
+#endif  // CONTENT_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_MANAGER_ANDROID_H_