Add two libcros interfaces for handwriting: SendHandwritingStrokes and CancelHandwriting.

chromeos_input_method.cc

Index: chromeos_input_method.cc
diff --git a/chromeos_input_method.cc b/chromeos_input_method.cc
index 132ff0fc14ffd9090350aff1102791fd1fa4338b..009df5bed8fa1ab5f5f0c8b9ec7db52fffa85757 100644
--- a/chromeos_input_method.cc
+++ b/chromeos_input_method.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -18,6 +18,7 @@
 #include <stack>
 #include <utility>
 
+#include "base/scoped_ptr.h"
 #include "base/singleton.h"
 #include "chromeos/string.h"  // for chromeos::SplitStringUsing.
 #include "ibus_input_methods.h"
@@ -651,6 +652,37 @@ class InputMethodStatusConnection {
     return true;
   }
 
+  void SendHandwritingStrokes(const HandwritingStrokes& strokes) {
+    if (strokes.size() < 2) {
+      LOG(WARNING) << "Empty stroke data or a single dot is passed.";
+      return;
+    }
+
+    IBusInputContext* context = GetInputContext(input_context_path_, ibus_);
+    if (!context) {
+      return;
+    }
+
+    const size_t raw_strokes_size = strokes.size() * 2;

[Peng, 2011/04/27 14:23:11]

Maybe we could use ((double*)&strokes[0]) and avoid an additional copy here.

http://stackoverflow.com/questions/2923272/how-to-convert-vector-to-array-c

[Yusuke Sato, 2011/05/02 05:22:26]

I know it's safe to use the internal buffer of std::vector as C array, but what
about std::pair? The variable is not a vector<double> but
vector<pair<double,double> >, and as far as I know the C++ standard does not
guarantee that std::pair's layout is always compatible with C struct. To avoid
unexpected behavior in the future, let me keep the current code.

On 2011/04/27 14:23:11, Peng wrote:

[Peng, 2011/05/02 14:11:47]

Yeah. It needs change pair to double or double[2] to make it safer.

+    scoped_array<double> raw_strokes(new double[raw_strokes_size]);
+    for (size_t n = 0; n < strokes.size(); ++n) {
+      raw_strokes[n * 2] = strokes[n].first;  // x
+      raw_strokes[n * 2 + 1] = strokes[n].second;  // y
+    }
+    ibus_input_context_process_hand_writing_event(
+        context, raw_strokes.get(), raw_strokes_size);
+    g_object_unref(context);
+  }
+
+  void CancelHandwriting(int n_strokes) {
+    IBusInputContext* context = GetInputContext(input_context_path_, ibus_);
+    if (!context) {
+      return;
+    }
+    ibus_input_context_cancel_hand_writing(context, n_strokes);
+    g_object_unref(context);
+  }
+
  private:
   friend struct DefaultSingletonTraits<InputMethodStatusConnection>;
   InputMethodStatusConnection()
@@ -1181,4 +1213,18 @@ std::string ChromeOSGetKeyboardOverlayId(const std::string& input_method_id) {
   return "";
 }
 
+extern "C"
+void ChromeOSSendHandwritingStrokes(InputMethodStatusConnection* connection,
+                                    const HandwritingStrokes& strokes) {
+  g_return_if_fail(connection);
+  connection->SendHandwritingStrokes(strokes);
+}
+
+extern "C"
+void ChromeOSCancelHandwriting(InputMethodStatusConnection* connection,
+                               int n_strokes) {
+  g_return_if_fail(connection);
+  connection->CancelHandwriting(n_strokes);
+}
+
 }  // namespace chromeos