ui/android/overscroll_refresh_handler.h

// Copyright 2016 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 UI_ANDROID_OVERSCROLL_REFRESH_HANDLER_H_
#define UI_ANDROID_OVERSCROLL_REFRESH_HANDLER_H_

#include "base/android/scoped_java_ref.h"
#include "ui/android/ui_android_export.h"

namespace ui {

class UI_ANDROID_EXPORT OverscrollRefreshHandler {
 public:
  explicit OverscrollRefreshHandler(
      const base::android::JavaRef<jobject>& j_overscroll_refresh_handler);

  // Note: the following methods are virtual because this class is overridden
  // for testing in overscroll_refresh_unittest.cc

  virtual ~OverscrollRefreshHandler();

  // Signals the start of an overscrolling pull. Returns whether the handler
  // will consume the overscroll gesture, in which case it will receive the
  // remaining pull updates.
  virtual bool PullStart();

  // Signals a pull update, where |delta| is in device pixels.
  virtual void PullUpdate(float delta);

  // Signals the release of the pull, and whether the release is allowed to
  // trigger the refresh action.
  virtual void PullRelease(bool allow_refresh);

  // Reset the active pull state.
  virtual void PullReset();

 private:
  base::android::ScopedJavaGlobalRef<jobject> j_overscroll_refresh_handler_;
};

}  // namespace ui

#endif  // UI_ANDROID_OVERSCROLL_REFRESH_HANDLER_H_