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

services/keyboard_native/key_layout.cc

Index: services/keyboard_native/key_layout.cc
diff --git a/services/keyboard_native/key_layout.cc b/services/keyboard_native/key_layout.cc
index 13957cb4b7ba347c43712b0a58fc89489b868c6b..53b849d616dbc2a8f01f604ff6435500604f2b79 100644
--- a/services/keyboard_native/key_layout.cc
+++ b/services/keyboard_native/key_layout.cc
@@ -5,36 +5,100 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/macros.h"
+#include "mojo/tools/embed/data.h"
+#include "services/keyboard_native/kActionIcon.h"
+#include "services/keyboard_native/kDeleteIcon.h"
+#include "services/keyboard_native/kLowerCaseIcon.h"
+#include "services/keyboard_native/kUpperCaseIcon.h"
 #include "services/keyboard_native/key_layout.h"
 #include "skia/ext/refptr.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 "third_party/skia/include/core/SkTypeface.h"
+#include "ui/gfx/codec/png_codec.h"
+#include "ui/gfx/geometry/point.h"
+#include "ui/gfx/geometry/rect.h"
+#include "ui/gfx/geometry/rect_f.h"
 
 namespace keyboard {
 
-KeyLayout::TextKey::TextKey(
-    const char* text,
-    base::Callback<void(const TextKey&)> touch_up_callback)
-    : text_(text), touch_up_callback_(touch_up_callback) {
-}
+// An implementation of Key that draws itself as ASCII text.
+class KeyLayout::TextKey : public Key {
+ public:
+  TextKey(const char* text,
+          base::Callback<void(const TextKey&)> touch_up_callback)
+      : text_(text), touch_up_callback_(touch_up_callback) {}
+
+  ~TextKey() override {}
+
+  void Draw(SkCanvas* canvas,
+            const SkPaint& paint,
+            const gfx::RectF& rect) override {
+    float text_baseline_offset = rect.height() / 5.0f;
+    canvas->drawText(text_, strlen(text_), rect.x() + (rect.width() / 2.0f),
+                     rect.y() + rect.height() - text_baseline_offset, paint);
+  }
 
-KeyLayout::TextKey::~TextKey() {
-}
+  const char* ToText() const override { return text_; }
 
-void KeyLayout::TextKey::Draw(SkCanvas* canvas,
-                              SkPaint paint,
-                              const gfx::RectF& rect) {
-  float text_baseline_offset = rect.height() / 5.0f;
-  canvas->drawText(text_, strlen(text_), rect.x() + (rect.width() / 2.0f),
-                   rect.y() + rect.height() - text_baseline_offset, paint);
-}
+  void OnTouchUp() override { touch_up_callback_.Run(*this); }
 
-const char* KeyLayout::TextKey::ToText() const {
-  return text_;
-}
+ private:
+  const char* text_;
+  base::Callback<void(const TextKey&)> touch_up_callback_;
 
-void KeyLayout::TextKey::OnTouchUp() {
-  touch_up_callback_.Run(*this);
-}
+  DISALLOW_COPY_AND_ASSIGN(TextKey);
+};
+
+// An implementation of Key that draws itself as an image.
+class ImageKey : public KeyLayout::Key {
+ public:
+  ImageKey(const char* text,
+           base::Callback<void(const KeyLayout::TextKey&)> touch_up_callback,
+           const mojo::embed::Data& data)
+      : text_key_(text, touch_up_callback), bitmap_valid_(false), bitmap_() {
+    bool result = gfx::PNGCodec::Decode(
+        reinterpret_cast<const unsigned char*>(data.data), data.size, &bitmap_);
+    bitmap_valid_ = result && bitmap_.width() > 0 && bitmap_.height() > 0;
+    DCHECK(bitmap_valid_);
+  }
+  ~ImageKey() override {}
+
+  // Key implementation.
+  void Draw(SkCanvas* canvas,
+            const SkPaint& paint,
+            const gfx::RectF& rect) override {
+    // If our bitmap is somehow invalid, default to drawing the text of the key.
+    if (!bitmap_valid_) {
+      text_key_.Draw(canvas, paint, rect);
+      return;
+    }
+
+    float width_scale = rect.width() / bitmap_.width();
+    float height_scale = rect.height() / bitmap_.height();
+    float scale = width_scale > height_scale ? height_scale : width_scale;
+    float target_width = bitmap_.width() * scale;
+    float target_height = bitmap_.height() * scale;
+    float delta_width = rect.width() - target_width;
+    float target_x = rect.x() + (delta_width / 2.0f);
+    float delta_height = rect.height() - target_height;
+    float target_y = rect.y() + (delta_height / 2.0f);
+    canvas->drawBitmapRect(
+        bitmap_,
+        SkRect::MakeXYWH(target_x, target_y, target_width, target_height),
+        &paint);
+  }
+  const char* ToText() const override { return text_key_.ToText(); }
+  void OnTouchUp() override { text_key_.OnTouchUp(); }
+
+ private:
+  KeyLayout::TextKey text_key_;
+  bool bitmap_valid_;
+  SkBitmap bitmap_;
+
+  DISALLOW_COPY_AND_ASSIGN(ImageKey);
+};
 
 KeyLayout::KeyLayout()
     : on_text_callback_(),
@@ -199,6 +263,15 @@ void KeyLayout::InitKeyMaps() {
   base::Callback<void(const TextKey&)> switch_to_symbols_callback =
       base::Bind(&KeyLayout::OnKeySwitchToSymbols, weak_factory_.GetWeakPtr());
 
+  ImageKey* switch_to_upper_case_image_key = new ImageKey(
+      "/\\", switch_to_upper_case_callback, keyboard_native::kUpperCaseIcon);
+  ImageKey* switch_to_lower_case_image_key = new ImageKey(
+      "\\/", switch_to_lower_case_callback, keyboard_native::kLowerCaseIcon);
+  ImageKey* delete_image_key =
+      new ImageKey("<-", delete_callback, keyboard_native::kDeleteIcon);
+  ImageKey* action_image_key =
+      new ImageKey(":)", do_nothing_callback, keyboard_native::kActionIcon);
+
   std::vector<Key*> lower_case_key_map_row_one = {
       new TextKey("q", emit_text_callback),
       new TextKey("w", emit_text_callback),
@@ -223,7 +296,7 @@ void KeyLayout::InitKeyMaps() {
       new TextKey("l", emit_text_callback)};
 
   std::vector<Key*> lower_case_key_map_row_three = {
-      new TextKey("/\\", switch_to_upper_case_callback),
+      switch_to_upper_case_image_key,
       new TextKey("z", emit_text_callback),
       new TextKey("x", emit_text_callback),
       new TextKey("c", emit_text_callback),
@@ -231,14 +304,14 @@ void KeyLayout::InitKeyMaps() {
       new TextKey("b", emit_text_callback),
       new TextKey("n", emit_text_callback),
       new TextKey("m", emit_text_callback),
-      new TextKey("del", delete_callback)};
+      delete_image_key};
 
   std::vector<Key*> lower_case_key_map_row_four = {
       new TextKey("sym", switch_to_symbols_callback),
       new TextKey(",", emit_text_callback),
       new TextKey(" ", emit_text_callback),
       new TextKey(".", emit_text_callback),
-      new TextKey("act", do_nothing_callback)};
+      action_image_key};
 
   lower_case_key_map_ = {lower_case_key_map_row_one,
                          lower_case_key_map_row_two,
@@ -269,7 +342,7 @@ void KeyLayout::InitKeyMaps() {
       new TextKey("L", emit_text_callback)};
 
   std::vector<Key*> upper_case_key_map_row_three = {
-      new TextKey("\\/", switch_to_lower_case_callback),
+      switch_to_lower_case_image_key,
       new TextKey("Z", emit_text_callback),
       new TextKey("X", emit_text_callback),
       new TextKey("C", emit_text_callback),
@@ -277,14 +350,14 @@ void KeyLayout::InitKeyMaps() {
       new TextKey("B", emit_text_callback),
       new TextKey("N", emit_text_callback),
       new TextKey("M", emit_text_callback),
-      new TextKey("DEL", delete_callback)};
+      delete_image_key};
 
   std::vector<Key*> upper_case_key_map_row_four = {
       new TextKey("SYM", switch_to_symbols_callback),
       new TextKey(",", emit_text_callback),
       new TextKey(" ", emit_text_callback),
       new TextKey(".", emit_text_callback),
-      new TextKey("ACT", do_nothing_callback)};
+      action_image_key};
 
   upper_case_key_map_ = {upper_case_key_map_row_one,
                          upper_case_key_map_row_two,
@@ -323,7 +396,7 @@ void KeyLayout::InitKeyMaps() {
       new TextKey(";", emit_text_callback),
       new TextKey("!", emit_text_callback),
       new TextKey("?", emit_text_callback),
-      new TextKey("del", delete_callback)};
+      delete_image_key};
 
   std::vector<Key*> symbols_key_map_row_four = {
       new TextKey("ABC", switch_to_lower_case_callback),
@@ -332,12 +405,12 @@ void KeyLayout::InitKeyMaps() {
       new TextKey(" ", emit_text_callback),
       new TextKey("/", emit_text_callback),
       new TextKey(".", emit_text_callback),
-      new TextKey("act", do_nothing_callback)};
+      action_image_key};
 
   symbols_key_map_ = {symbols_key_map_row_one,
                       symbols_key_map_row_two,
                       symbols_key_map_row_three,
                       symbols_key_map_row_four};
 }
-
-}  // namespace keyboard
+}
+// namespace keyboard