Files
tdesktop/Telegram/SourceFiles/info/info_flexible_scroll.h

58 lines
1.6 KiB
C++

/*
This file is part of Telegram Desktop,
the official desktop application for the Telegram messaging service.
For license and copyright information please follow this link:
https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
*/
#pragma once
#include "ui/widgets/scroll_area.h"
#include "ui/effects/animations.h"
#include "ui/rp_widget.h"
namespace Info {
extern const char kAlternativeScrollProcessing[];
struct FlexibleScrollData {
rpl::event_stream<int> contentHeightValue;
rpl::event_stream<int> fillerWidthValue;
rpl::event_stream<> backButtonEnables;
};
class FlexibleScrollHelper final {
public:
FlexibleScrollHelper(
not_null<Ui::ScrollArea*> scroll,
not_null<Ui::RpWidget*> inner,
not_null<Ui::RpWidget*> pinnedToTop,
Fn<void(QMargins)> setPaintPadding,
Fn<void(rpl::producer<not_null<QEvent*>>&&)> setViewport,
FlexibleScrollData &data);
private:
void setupScrollAnimation();
void setupScrollHandling();
void setupScrollHandlingWithFilter();
void scrollToY(int value);
void applyScrollToPinnedLayout(int scrollCurrent);
const not_null<Ui::ScrollArea*> _scroll;
const not_null<Ui::RpWidget*> _inner;
const not_null<Ui::RpWidget*> _pinnedToTop;
const Fn<void(QMargins)> _setPaintPadding;
const Fn<void(rpl::producer<not_null<QEvent*>>&&)> _setViewport;
FlexibleScrollData &_data;
Ui::Animations::Basic _scrollAnimation;
int _scrollTopFrom = 0;
int _scrollTopTo = 0;
crl::time _timeOffset = 0;
int _lastScrollApplied = 0;
int _scrollTopPrevious = 0;
bool _applyingFakeScrollState = false;
rpl::lifetime _filterLifetime;
};
} // namespace Info