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// Copyright 2014 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 "athena/util/drag_handle.h"
#include "ui/views/background.h"
#include "ui/views/view.h"
namespace athena {
namespace {
const SkColor kDragHandleColorNormal = SK_ColorGRAY;
const SkColor kDragHandleColorHot = SK_ColorWHITE;
// This view notifies its delegate of the touch scroll gestures performed on it.
class DragHandleView : public views::View {
public:
DragHandleView(DragHandleScrollDirection scroll_direction,
DragHandleScrollDelegate* delegate,
int preferred_width,
int preferred_height);
~DragHandleView() override;
private:
void SetColor(SkColor color);
void SetIsScrolling(bool scrolling);
// views::View:
virtual gfx::Size GetPreferredSize() const override;
virtual void OnGestureEvent(ui::GestureEvent* event) override;
bool scroll_in_progress_;
DragHandleScrollDelegate* delegate_;
DragHandleScrollDirection scroll_direction_;
SkColor color_;
float scroll_start_location_;
const int preferred_width_;
const int preferred_height_;
DISALLOW_COPY_AND_ASSIGN(DragHandleView);
};
DragHandleView::DragHandleView(DragHandleScrollDirection scroll_direction,
DragHandleScrollDelegate* delegate,
int preferred_width,
int preferred_height)
: scroll_in_progress_(false),
delegate_(delegate),
scroll_direction_(scroll_direction),
color_(SK_ColorTRANSPARENT),
preferred_width_(preferred_width),
preferred_height_(preferred_height) {
SetColor(kDragHandleColorNormal);
}
DragHandleView::~DragHandleView() {
}
void DragHandleView::SetColor(SkColor color) {
if (color_ == color)
return;
color_ = color;
set_background(views::Background::CreateSolidBackground(color_));
SchedulePaint();
}
void DragHandleView::SetIsScrolling(bool scrolling) {
if (scroll_in_progress_ == scrolling)
return;
scroll_in_progress_ = scrolling;
if (!scroll_in_progress_)
scroll_start_location_ = 0;
}
// views::View:
gfx::Size DragHandleView::GetPreferredSize() const {
return gfx::Size(preferred_width_, preferred_height_);
}
void DragHandleView::OnGestureEvent(ui::GestureEvent* event) {
SkColor change_color = SK_ColorTRANSPARENT;
if (event->type() == ui::ET_GESTURE_BEGIN &&
event->details().touch_points() == 1) {
change_color = kDragHandleColorHot;
} else if (event->type() == ui::ET_GESTURE_END &&
event->details().touch_points() == 1) {
change_color = kDragHandleColorNormal;
}
if (change_color != SK_ColorTRANSPARENT) {
SetColor(change_color);
event->SetHandled();
return;
}
if (event->type() == ui::ET_GESTURE_SCROLL_BEGIN) {
if (scroll_in_progress_)
return;
float delta;
if (scroll_direction_ == DRAG_HANDLE_VERTICAL) {
delta = event->details().scroll_y_hint();
scroll_start_location_ = event->root_location().y();
} else {
delta = event->details().scroll_x_hint();
scroll_start_location_ = event->root_location().x();
}
delegate_->HandleScrollBegin(delta);
SetIsScrolling(true);
event->SetHandled();
} else if (event->type() == ui::ET_GESTURE_SCROLL_END ||
event->type() == ui::ET_SCROLL_FLING_START) {
if (!scroll_in_progress_)
return;
float velocity = 0.0f;
if (event->type() == ui::ET_SCROLL_FLING_START)
velocity = event->details().velocity_x();
delegate_->HandleScrollEnd(velocity);
SetColor(kDragHandleColorNormal);
SetIsScrolling(false);
event->SetHandled();
} else if (event->type() == ui::ET_GESTURE_SCROLL_UPDATE) {
if (!scroll_in_progress_)
return;
float delta = scroll_direction_ == DRAG_HANDLE_VERTICAL
? event->root_location().y() - scroll_start_location_
: event->root_location().x() - scroll_start_location_;
delegate_->HandleScrollUpdate(delta);
event->SetHandled();
}
}
} // namespace
views::View* CreateDragHandleView(DragHandleScrollDirection scroll_direction,
DragHandleScrollDelegate* delegate,
int preferred_width,
int preferred_height) {
views::View* view = new DragHandleView(
scroll_direction, delegate, preferred_width, preferred_height);
return view;
}
} // namespace athena
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