Upstream android's fling animator.

BUG=none
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10823239

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@151327 0039d316-1c4b-4281-b951-d872f2087c98

webkit/glue/fling_animator_impl_android.cc

+// Copyright (c) 2012 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 "webkit/glue/fling_animator_impl_android.h"
+
+#include "base/android/jni_android.h"
+#include "base/android/scoped_java_ref.h"
+#include "base/logging.h"
+
+using namespace base::android;
+
+namespace webkit_glue {
+
+FlingAnimatorImpl::FlingAnimatorImpl()
+    : is_active_(false) {
+  // hold the global reference of the Java objects.
+  JNIEnv* env = AttachCurrentThread();
+  DCHECK(env);
+  ScopedJavaLocalRef<jclass> cls(GetClass(env, "android/widget/OverScroller"));
+  jmethodID constructor = GetMethodID(env, cls, "<init>",
+                                      "(Landroid/content/Context;)V");
+  ScopedJavaLocalRef<jobject> tmp(env, env->NewObject(cls.obj(), constructor,
+                                                      GetApplicationContext()));
+  DCHECK(tmp.obj());
+  java_scroller_.Reset(tmp);
+
+  fling_method_id_ = GetMethodID(env, cls, "fling", "(IIIIIIIIII)V");
+  abort_method_id_ = GetMethodID(env, cls, "abortAnimation", "()V");
+  compute_method_id_ = GetMethodID(env, cls, "computeScrollOffset", "()Z");
+  getX_method_id_ = GetMethodID(env, cls, "getCurrX", "()I");
+  getY_method_id_ = GetMethodID(env, cls, "getCurrY", "()I");
+}
+
+FlingAnimatorImpl::~FlingAnimatorImpl()
+{
+}
+
+void FlingAnimatorImpl::startFling(const WebKit::WebFloatPoint& velocity,
+                                   const WebKit::WebRect& range)
+{
+  DCHECK(velocity.x || velocity.y);
+  if (is_active_)
+    cancelFling();
+
+  is_active_ = true;
+
+  JNIEnv* env = AttachCurrentThread();
+  env->CallVoidMethod(java_scroller_.obj(), fling_method_id_, 0, 0,
+                      (int) -velocity.x, (int) -velocity.y,
+                      range.x, range.x + range.width,
+                      range.y, range.y + range.height, 0, 0);
+  CheckException(env);
+}
+
+void FlingAnimatorImpl::cancelFling()
+{
+  if (!is_active_)
+    return;
+
+  is_active_ = false;
+  JNIEnv* env = AttachCurrentThread();
+  env->CallVoidMethod(java_scroller_.obj(), abort_method_id_);
+  CheckException(env);
+}
+
+bool FlingAnimatorImpl::updatePosition()
+{
+  JNIEnv* env = AttachCurrentThread();
+  bool result = env->CallBooleanMethod(java_scroller_.obj(),
+                                       compute_method_id_);
+  CheckException(env);
+  return is_active_ = result;
+}
+
+WebKit::WebPoint FlingAnimatorImpl::getCurrentPosition()
+{
+  JNIEnv* env = AttachCurrentThread();
+  WebKit::WebPoint position(
+      env->CallIntMethod(java_scroller_.obj(), getX_method_id_),
+      env->CallIntMethod(java_scroller_.obj(), getY_method_id_));
+  CheckException(env);
+  return position;
+}
+
+} // namespace webkit_glue

webkit/glue/fling_animator_impl_android.h

+// Copyright (c) 2012 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 WEBKIT_GLUE_FLING_ANIMATOR_IMPL_ANDROID_H_
+#define WEBKIT_GLUE_FLING_ANIMATOR_IMPL_ANDROID_H_
+
+#include "base/android/scoped_java_ref.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebFlingAnimator.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebFloatPoint.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebPoint.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebRect.h"
+
+namespace webkit_glue {
+
+class FlingAnimatorImpl : public WebKit::WebFlingAnimator {
+ public:
+  FlingAnimatorImpl();
+  virtual ~FlingAnimatorImpl();
+
+  virtual void startFling(const WebKit::WebFloatPoint& velocity,
+                          const WebKit::WebRect& range);
+  // Returns true if the animation is not yet finished.
+  virtual bool updatePosition();
+  virtual WebKit::WebPoint getCurrentPosition();
+  virtual void cancelFling();
+
+ private:
+  bool is_active_;
+
+  // Java OverScroller instance and methods.
+  base::android::ScopedJavaGlobalRef<jobject> java_scroller_;
+  jmethodID fling_method_id_;
+  jmethodID abort_method_id_;
+  jmethodID compute_method_id_;
+  jmethodID getX_method_id_;
+  jmethodID getY_method_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(FlingAnimatorImpl);
+};
+
+} // namespace webkit_glue
+
+#endif // WEBKIT_GLUE_FLING_ANIMATOR_IMPL_ANDROID_H_

webkit/glue/webkit_glue.gypi

@@ -353,6 +353,8 @@
         'cpp_variant.h',
         'dom_operations.cc',
         'dom_operations.h',
+        'fling_animator_impl_android.cc',
+        'fling_animator_impl_android.h',
         'ftp_directory_listing_response_delegate.cc',
         'ftp_directory_listing_response_delegate.h',
         'gl_bindings_skia_cmd_buffer.cc',

webkit/glue/webkitplatformsupport_impl.cc

@@ -48,6 +48,10 @@
 #include "webkit/plugins/npapi/plugin_instance.h"
 #include "webkit/plugins/webplugininfo.h"
 
+#if defined(OS_ANDROID)
+#include "webkit/glue/fling_animator_impl_android.h"
+#endif
+
 #if defined(OS_LINUX)
 #include "v8/include/v8.h"
 #endif
@@ -789,4 +793,10 @@ void WebKitPlatformSupportImpl::didStopWorkerRunLoop(
   worker_task_runner->OnWorkerRunLoopStopped(runLoop);
 }
 
+#if defined(OS_ANDROID)
+WebKit::WebFlingAnimator* WebKitPlatformSupportImpl::createFlingAnimator() {
+  return new FlingAnimatorImpl();
+}
+#endif
+
 }  // namespace webkit_glue

webkit/glue/webkitplatformsupport_impl.h

@@ -32,6 +32,7 @@ struct WebPluginInfo;
 }
 
 namespace WebKit {
+class WebFlingAnimator;
 class WebSocketStreamHandle;
 }
 
@@ -152,6 +153,10 @@ class WEBKIT_GLUE_EXPORT WebKitPlatformSupportImpl :
   virtual void didStopWorkerRunLoop(
       const WebKit::WebWorkerRunLoop& runLoop) OVERRIDE;
 
+#if defined(OS_ANDROID)
+  virtual WebKit::WebFlingAnimator* createFlingAnimator();
+#endif
+
  private:
   void DoTimeout() {
     if (shared_timer_func_ && !shared_timer_suspended_)