Tracking composition range on the browser side (Aura)

content/browser/renderer_host/text_input_manager.h

 // Copyright 2016 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_RENDERER_HOST_TEXT_INPUT_MANAGER_H__
 #define CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_MANAGER_H__
 
 #include <unordered_map>
 #include <utility>
 
 #include "base/observer_list.h"
 #include "content/common/content_export.h"
 #include "content/common/text_input_state.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/selection_bound.h"
 
 struct ViewHostMsg_SelectionBounds_Params;
 
+namespace gfx {

[EhsanK, 2016/07/07 22:10:58]

Not quite sure if space is needed.

[kenrb, 2016/07/08 18:13:42]

It isn't.

[EhsanK, 2016/07/11 18:07:21]

Acknowledged.

+class Range;
+}
+
 namespace content {

[EhsanK, 2016/07/07 22:10:58]

Same dilemma, but maybe a different case than above.

[kenrb, 2016/07/08 18:13:42]

A blank line here is appropriate.

[EhsanK, 2016/07/11 18:07:21]

Acknowledged.

 class RenderWidgetHostImpl;
 class RenderWidgetHostView;
 class RenderWidgetHostViewBase;
 class WebContents;
 
 // A class which receives updates of TextInputState from multiple sources and
 // decides what the new TextInputState is. It also notifies the observers when
 // text input state is updated.
 class CONTENT_EXPORT TextInputManager {
  public:
@@ skipping 33 matching lines @@
   RenderWidgetHostImpl* GetActiveWidget() const;
 
   // Returns the TextInputState corresponding to |active_view_|.
   // Users of this method should not hold on to the pointer as it might become
   // dangling if the TextInputManager or |active_view_| might go away.
   const TextInputState* GetTextInputState();
 
   // Returns the rect between selection bounds for the |active_view_|.
   gfx::Rect GetSelectionBoundsRect();
 
+  // Returns a vector of rects for the character bounds of the active widget.
+  const std::vector<gfx::Rect>* GetCompositionCharacterBounds();

[kenrb, 2016/07/08 18:13:42]

In RenderWidgetHostViewAura you call this without checking the return for
nullptr, but the implementation looks like it can return nullptr. Is returning a
value normally guaranteed?

Either way, it would be good to add to the comment saying when it can return
null.

[EhsanK, 2016/07/11 18:07:21]

In RWHVAura we check if there is an active widget first, which guarantees this
will return something.

I refactored the comments by explaining above them that for these Get* methods
we will return nullptr if there is no active widgets.

+
   // ---------------------------------------------------------------------------
   // The following methods are called by RWHVs on the tab to update their IME-
   // related state.
 
   // Updates the TextInputState for |view|.
   void UpdateTextInputState(RenderWidgetHostViewBase* view,
                             const TextInputState& state);
 
   // The current IME composition has been cancelled on the renderer side for
   // the widget corresponding to |view|.
   void ImeCancelComposition(RenderWidgetHostViewBase* view);
 
   // Updates the selection bounds for the |view|. In Aura, selection bounds are
   // used to provide the InputMethod with the position of the caret, e.g., in
   // setting the position of the ui::ImeWindow.
   void SelectionBoundsChanged(RenderWidgetHostViewBase* view,
                               const ViewHostMsg_SelectionBounds_Params& params);
 
+  // Called when the composition range and/or character bounds have changed.
+  void ImeCompositionRangeChanged(
+      RenderWidgetHostViewBase* view,
+      const gfx::Range& range,
+      const std::vector<gfx::Rect>& character_bounds);
+
   // Registers the given |view| for tracking its TextInputState. This is called
   // by any view which has updates in its TextInputState (whether tab's RWHV or
   // that of a child frame). The |view| must unregister itself before being
   // destroyed (i.e., call TextInputManager::Unregister).
   void Register(RenderWidgetHostViewBase* view);
 
   // Clears the TextInputState from the |view|. If |view == active_view_|, this
   // call will lead to a TextInputState update since the TextInputState.type
   // should be reset to none.
   void Unregister(RenderWidgetHostViewBase* view);
@@ skipping 20 matching lines @@
   struct SelectionRegion {
     SelectionRegion();
     SelectionRegion(const SelectionRegion& other);
 
     // The begining of the selection region.
     gfx::SelectionBound anchor;
     // The end of the selection region (caret position).
     gfx::SelectionBound focus;
   };
 
+  // Ccomposition range information.
+  struct CompositionRangeInfo {

[EhsanK, 2016/07/07 22:10:58]

We do not store gfx::Range for Aura since it was not used. But it is used for
Mac so I think it is best to have this as a struct.

+    CompositionRangeInfo();
+    CompositionRangeInfo(const CompositionRangeInfo& other);
+    ~CompositionRangeInfo();
+
+    std::vector<gfx::Rect> character_bounds;
+  };
+
   // This class is used to create maps which hold specific IME state for a
   // view.
   template <class Value>
   class ViewMap : public std::unordered_map<RenderWidgetHostViewBase*, Value> {
   };
 
   void NotifyObserversAboutInputStateUpdate(RenderWidgetHostViewBase* view,
                                             bool did_update_state);
 
   // The view with active text input state, i.e., a focused <input> element.
   // It will be nullptr if no such view exists. Note that the active view
   // cannot have a |TextInputState.type| of ui::TEXT_INPUT_TYPE_NONE.
   RenderWidgetHostViewBase* active_view_;
 
   ViewMap<TextInputState> text_input_state_map_;
 
   // Text selection bounds information for registered views.
   ViewMap<SelectionRegion> selection_region_map_;
+  ViewMap<CompositionRangeInfo> composition_range_info_map_;
 
   base::ObserverList<Observer> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(TextInputManager);
 };
 }
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_TEXT_INPUT_MANAGER_H__