Add spellcheck and word suggestion to the prediction service

examples/keyboard_client/keyboard_client.cc

Index: examples/keyboard_client/keyboard_client.cc
diff --git a/examples/keyboard_client/keyboard_client.cc b/examples/keyboard_client/keyboard_client.cc
index a9ef5e1412fbc6063abef7e286ac09cf4d7dff57..933966bacfc1a311c10676b1615f6ba910f73744 100644
--- a/examples/keyboard_client/keyboard_client.cc
+++ b/examples/keyboard_client/keyboard_client.cc
@@ -219,16 +219,7 @@ class KeyboardDelegate : public mojo::ApplicationDelegate,
 
   void CommitText(const mojo::String& text,
                   int32_t new_cursor_position) override {
-    std::string combined(text_[1]);
-    combined.append(text);
-    SkRect bounds;
-    text_paint_.measureText(combined.data(), combined.size(), &bounds);
-    if (bounds.width() > text_view_->bounds().width) {
-      text_[0] = text_[1];
-      text_[1] = text;
-    } else {
-      text_[1].append(text);
-    }
+    text_.append(text);
     DrawText();
   }
 
@@ -236,10 +227,10 @@ class KeyboardDelegate : public mojo::ApplicationDelegate,
                              int32_t after_length) override {
     // treat negative and zero |before_length| values as no-op.
     if (before_length > 0) {
-      if (before_length > static_cast<int32_t>(text_[1].size())) {
-        before_length = text_[1].size();
+      if (before_length > static_cast<int32_t>(text_.size())) {
+        before_length = text_.size();
       }
-      text_[1].erase(text_[1].end() - before_length, text_[1].end());
+      text_.erase(text_.end() - before_length, text_.end());
     }
     DrawText();
   }
@@ -316,15 +307,46 @@ class KeyboardDelegate : public mojo::ApplicationDelegate,
 
     float row_height = text_view_height_ / 2.0f;
     float text_baseline_offset = row_height / 5.0f;
-
-    if (!text_[0].empty()) {
-      canvas->drawText(text_[0].data(), text_[0].size(), 0.0f,
-                       row_height - text_baseline_offset, text_paint_);
-    }
-
-    if (!text_[1].empty()) {
-      canvas->drawText(text_[1].data(), text_[1].size(), 0.0f,
-                       (2.0f * row_height) - text_baseline_offset, text_paint_);
+    if (!text_.empty()) {
+      SkRect sk_rect;
+      text_paint_.measureText((const void*)(text_.c_str()),
+                              strlen(text_.c_str()), &sk_rect);
+
+      if (sk_rect.width() > text_view_->bounds().width) {
+        char reverse_text[text_.length() + 1];
+        for (unsigned int i = 0; i < text_.length(); i++) {
+          reverse_text[i] = text_[text_.length() - i - 1];

[APW, 2015/07/31 22:36:43]

use either a reverse iterator or create a copy of the string and std::reverse()
it.  Also this should be a string not a char array - char array is scary

[riajiang, 2015/08/01 01:23:08]

Done.

+        }
+        reverse_text[text_.length()] = '\0';
+
+        size_t processed1 = text_paint_.breakText((const void*)(reverse_text),
+                                                  strlen(reverse_text),
+                                                  text_view_->bounds().width);
+        size_t processed2 = text_paint_.breakText(
+            (const void*)(reverse_text + processed1),
+            strlen(reverse_text) - processed1, text_view_->bounds().width);
+        if (processed1 + processed2 < text_.length()) {
+          canvas->drawText(
+              text_.data() + (text_.length() - processed1), processed1, 0.0f,
+              (2.0f * row_height) - text_baseline_offset, text_paint_);
+          canvas->drawText(
+              text_.data() + (text_.length() - processed1 - processed2),
+              processed2, 0.0f, row_height - text_baseline_offset, text_paint_);
+        } else {
+          size_t processed3 = text_paint_.breakText(
+              (const void*)(text_.c_str()), strlen(text_.c_str()),
+              text_view_->bounds().width);
+          canvas->drawText(text_.data(), processed3, 0.0f,
+                           row_height - text_baseline_offset, text_paint_);
+          canvas->drawText(
+              text_.data() + processed3, strlen(text_.c_str()) - processed3,
+              0.0f, (2.0f * row_height) - text_baseline_offset, text_paint_);
+        }
+      } else {
+        canvas->drawText(text_.data(), text_.size(), 0.0f,

[APW, 2015/07/31 22:36:43]

just to make things a bit easier to understand, can you make functions for
drawing the first line and the second line?

[riajiang, 2015/08/01 01:23:08]

Done.

+                         (2.0f * row_height) - text_baseline_offset,
+                         text_paint_);
+      }
     }
 
     canvas->flush();
@@ -352,7 +374,7 @@ class KeyboardDelegate : public mojo::ApplicationDelegate,
   scoped_ptr<ViewTextureUploader> text_view_texture_uploader_;
   scoped_ptr<ViewTextureUploader> root_view_texture_uploader_;
   int text_view_height_;
-  std::string text_[2];
+  std::string text_;
   SkPaint text_paint_;
   base::WeakPtrFactory<KeyboardDelegate> weak_factory_;