Add the ability for keys to be drawn as an image.

services/keyboard_native/key_layout.h

 // Copyright 2015 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 SERVICES_KEYBOARD_NATIVE_KEY_LAYOUT_H_
 #define SERVICES_KEYBOARD_NATIVE_KEY_LAYOUT_H_
 
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "mojo/public/cpp/bindings/callback.h"
 #include "mojo/services/geometry/public/interfaces/geometry.mojom.h"
+#include "mojo/tools/embed/data.h"
 #include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkImageDecoder.h"
+#include "third_party/skia/include/core/SkStream.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/rect.h"
 
 namespace keyboard {
 
 // Represents a drawable keyboard.
 class KeyLayout {
  public:
   // All keys represented by this KeyBoard layout will implement the Key
   // interface.
@@ skipping 47 matching lines @@
     const char* ToText() const override;
     void OnTouchUp() override;
 
    private:
     const char* text_;
     base::Callback<void(const TextKey&)> touch_up_callback_;
 
     DISALLOW_COPY_AND_ASSIGN(TextKey);
   };
 
+  // An implementation of Key that draws itself as an image.
+  class ImageKey : public TextKey {

[jamesr, 2015/05/27 23:30:31]

why does this inherit from TextKey? inheriting from a concrete class in C++ (as
opposed to an abstract interface) is best avoided as there are lots of corner
cases that behave in really strange ways like accessing a virtual during a
c'tor/d'tor. much better to put common functionality in a type that can be
embedded instead of inherited from

[APW, 2015/05/28 17:54:25]

Done.

+   public:
+    ImageKey(const char* text,
+             base::Callback<void(const TextKey&)> touch_up_callback,
+             const mojo::embed::Data& data);
+    ~ImageKey() override;
+    void Draw(SkCanvas* canvas, SkPaint paint, const gfx::RectF& rect) override;
+
+   private:
+    SkBitmap bitmap_;
+
+    DISALLOW_COPY_AND_ASSIGN(ImageKey);
+  };
+
   // initializes the *_layout_ vectors.
   void InitLayouts();
 
   // initializes the *_key_map_ vectors.
   void InitKeyMaps();
 
   // A TextKey callback that does nothing.
   void OnKeyDoNothing(const TextKey& key);
 
   // A TextKey callback that calls on_text_callback_ with the text of the
@@ skipping 23 matching lines @@
   std::vector<std::vector<Key*>> upper_case_key_map_;
   std::vector<std::vector<Key*>> symbols_key_map_;
   base::WeakPtrFactory<KeyLayout> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(KeyLayout);
 };
 
 }  // namespace keyboard
 
 #endif  // SERVICES_KEYBOARD_NATIVE_KEY_LAYOUT_H_