Initial support for accessible text fields and focus tracking in ARC++

chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc

Index: chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc
diff --git a/chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc b/chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc
index a4a92086903d75b413ad9a51b4221e2e0f2ca356..f36261556d01fb60ae69d99dac4d87769feb72c3 100644
--- a/chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc
+++ b/chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc
@@ -18,10 +18,9 @@ namespace {
 ui::AXEvent ToAXEvent(arc::mojom::AccessibilityEventType arc_event_type) {
   switch (arc_event_type) {
     case arc::mojom::AccessibilityEventType::VIEW_FOCUSED:
+      return ui::AX_EVENT_FOCUS;

[hidehiko, 2017/03/21 03:43:23]

nit: unnecessary change.

[David Tseng, 2017/03/21 16:41:16]

Done.

     case arc::mojom::AccessibilityEventType::VIEW_ACCESSIBILITY_FOCUSED:
       return ui::AX_EVENT_FOCUS;
-    case arc::mojom::AccessibilityEventType::VIEW_ACCESSIBILITY_FOCUS_CLEARED:
-      return ui::AX_EVENT_BLUR;
     case arc::mojom::AccessibilityEventType::VIEW_CLICKED:
     case arc::mojom::AccessibilityEventType::VIEW_LONG_CLICKED:
       return ui::AX_EVENT_CLICKED;
@@ -83,6 +82,20 @@ bool GetBooleanProperty(arc::mojom::AccessibilityNodeInfoData* node,
   return it->second;
 }
 
+bool GetIntProperty(arc::mojom::AccessibilityNodeInfoData* node,
+                    arc::mojom::AccessibilityIntProperty prop,
+                    int32_t* out_value) {
+  if (!node->intProperties)
+    return false;
+
+  auto it = node->intProperties->find(prop);
+  if (it == node->intProperties->end())
+    return false;
+
+  *out_value = it->second;
+  return true;
+}
+
 bool GetStringProperty(arc::mojom::AccessibilityNodeInfoData* node,
                        arc::mojom::AccessibilityStringProperty prop,
                        std::string* out_value) {
@@ -219,10 +232,10 @@ void AXTreeSourceArc::NotifyAccessibilityEvent(
 
   ExtensionMsg_AccessibilityEventParams params;
   params.event_type = ToAXEvent(event_data->eventType);
+
   if (params.event_type == ui::AX_EVENT_FOCUS)
-    focused_node_id_ = params.id;
-  else if (params.event_type == ui::AX_EVENT_BLUR)
-    focused_node_id_ = -1;
+    focused_node_id_ = event_data->sourceId;
+
   params.tree_id = tree_id_;
   params.id = event_data->sourceId;
 
@@ -306,6 +319,7 @@ void AXTreeSourceArc::SerializeNode(mojom::AccessibilityNodeInfoData* node,
     return;
   out_data->id = node->id;
 
+  using AXIntProperty = arc::mojom::AccessibilityIntProperty;
   using AXStringProperty = arc::mojom::AccessibilityStringProperty;
   std::string text;
   if (GetStringProperty(node, AXStringProperty::TEXT, &text))
@@ -329,6 +343,15 @@ void AXTreeSourceArc::SerializeNode(mojom::AccessibilityNodeInfoData* node,
 
   if (out_data->role == ui::AX_ROLE_TEXT_FIELD && !text.empty())
     out_data->AddStringAttribute(ui::AX_ATTR_VALUE, text);
+
+  // Integer properties.
+  int32_t val;
+  if (GetIntProperty(node, AXIntProperty::TEXT_SELECTION_START, &val) &&
+      val >= 0)

[Luis Héctor Chávez, 2017/03/17 22:13:20]

nit: add braces since the condition spans two lines.

[David Tseng, 2017/03/21 16:41:16]

STyle guide says
"In general, curly braces are not required for single-line statements, but they
are allowed if you like them; conditional or loop statements with complex
conditions or statements may be more readable with curly braces. Some projects
require that an if must always always have an accompanying brace."

and I've always omitted braces for single statement if's.
 

+    out_data->AddIntAttribute(ui::AX_ATTR_TEXT_SEL_START, val);
+
+  if (GetIntProperty(node, AXIntProperty::TEXT_SELECTION_END, &val) && val >= 0)
+    out_data->AddIntAttribute(ui::AX_ATTR_TEXT_SEL_END, val);
 }
 
 void AXTreeSourceArc::Reset() {