Add spellcheck and word suggestion to the prediction service

services/keyboard_native/text_update_key.cc

+// 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.
+
+#include <string>
+
+#include "services/keyboard_native/text_update_key.h"
+#include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkPaint.h"
+#include "third_party/skia/include/core/SkScalar.h"
+#include "ui/gfx/geometry/rect_f.h"
+
+namespace keyboard {
+
+TextUpdateKey::TextUpdateKey(
+    std::string text,
+    base::Callback<void(const TextUpdateKey&)> touch_up_callback)
+    : text_(text), touch_up_callback_(touch_up_callback) {
+}
+
+TextUpdateKey::~TextUpdateKey() {
+}
+
+// Key implementation.
+void TextUpdateKey::Draw(SkCanvas* canvas,
+                         const SkPaint& paint,
+                         const gfx::RectF& rect) {
+  std::string text_to_fit = text_;
+  SkRect bounds;
+  SkPaint paint_copy = paint;
+  paint_copy.measureText((const void*)(text_.c_str()), strlen(text_.c_str()),
+                         &bounds);
+  bool text_need_scale = false;
+  if (bounds.width() > rect.width() * 0.8) {
+    text_need_scale = true;
+
+    paint_copy.setTextScaleX(SkFloatToScalar(0.6));
+    paint_copy.measureText((const void*)(text_.c_str()), strlen(text_.c_str()),
+                           &bounds);
+    paint_copy.setTextScaleX(SkIntToScalar(1));
+    if (bounds.width() > rect.width() * 0.8) {
+      int dot_count = SkScalarTruncToInt((SkScalarToFloat(bounds.width()) -
+                                          SkScalarToFloat(rect.width()) * 0.8) /
+                                         SkScalarToFloat(bounds.width()) *
+                                         strlen(text_.c_str())) +
+                      1;
+      int dot_count_in_text = dot_count < 3 ? dot_count : 3;
+      std::string dots(dot_count_in_text, '.');
+      text_to_fit =
+          dots +
+          text_to_fit.substr(dot_count, text_to_fit.length() - dot_count);
+    }
+  }
+
+  float text_baseline_offset = rect.height() / 5.0f;
+  if (text_need_scale) {
+    paint_copy.setTextScaleX(SkFloatToScalar(0.6));
+  }
+  canvas->drawText(text_to_fit.c_str(), strlen(text_to_fit.c_str()),
+                   rect.x() + (rect.width() / 2.0f),
+                   rect.y() + rect.height() - text_baseline_offset, paint_copy);
+  paint_copy.setTextScaleX(SkIntToScalar(1));
+}
+
+const char* TextUpdateKey::ToText() const {
+  const char* text_char = text_.c_str();
+  return text_char;
+}
+
+void TextUpdateKey::OnTouchUp() {
+  touch_up_callback_.Run(*this);
+}
+
+void TextUpdateKey::ChangeText(std::string new_text) {
+  text_ = new_text;
+}
+}  // namespace keyboard