Gated history overscroll on load, removed ContinuousScroll.

Telegram/SourceFiles/history/history_view_pull_to_next_channel.cpp

@@ -28,7 +28,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "storage/storage_shared_media.h"
 #include "support/support_preload.h"
 #include "ui/chat/chat_style.h"
-#include "ui/chat/continuous_scroll.h"
 #include "ui/widgets/elastic_scroll.h"
 #include "ui/rect.h"
 #include "ui/rp_widget.h"
@@ -568,7 +567,7 @@ void PullToNextChannel::HintOverlay::paintEvent(QPaintEvent *e) {
 
 PullToNextChannel::PullToNextChannel(
 	not_null<Ui::RpWidget*> parent,
-	not_null<Ui::ContinuousScroll*> scroll,
+	not_null<Ui::ElasticScroll*> scroll,
 	not_null<Window::SessionController*> controller)
 : _parent(parent)
 , _scroll(scroll)

Telegram/SourceFiles/history/history_view_pull_to_next_channel.h

@@ -16,7 +16,7 @@ class HistoryInner;
 
 namespace Ui {
 class RpWidget;
-class ContinuousScroll;
+class ElasticScroll;
 struct ElasticScrollPosition;
 enum class ElasticScrollMovement;
 } // namespace Ui
@@ -31,7 +31,7 @@ class PullToNextChannel final {
 public:
 	PullToNextChannel(
 		not_null<Ui::RpWidget*> parent,
-		not_null<Ui::ContinuousScroll*> scroll,
+		not_null<Ui::ElasticScroll*> scroll,
 		not_null<Window::SessionController*> controller);
 	~PullToNextChannel();
 
@@ -58,7 +58,7 @@ private:
 	void jumpTo(not_null<History*> history);
 
 	const not_null<Ui::RpWidget*> _parent;
-	const not_null<Ui::ContinuousScroll*> _scroll;
+	const not_null<Ui::ElasticScroll*> _scroll;
 	const not_null<Window::SessionController*> _controller;
 	const base::unique_qptr<Indicator> _indicator;
 	const base::unique_qptr<HintOverlay> _hint;

Telegram/SourceFiles/history/history_widget.cpp

@@ -176,7 +176,6 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/chat/requests_bar.h"
 #include "ui/chat/chat_theme.h"
 #include "ui/chat/chat_style.h"
-#include "ui/chat/continuous_scroll.h"
 #include "ui/widgets/checkbox.h"
 #include "ui/widgets/elastic_scroll.h"
 #include "ui/widgets/popup_menu.h"
@@ -381,37 +380,37 @@ HistoryWidget::HistoryWidget(
 		handleScroll();
 	}, lifetime());
 	_scroll->setOverscrollTypes(
-		Ui::ElasticScroll::OverscrollType::None,
+		Ui::ElasticScroll::OverscrollType::Real,
 		Ui::ElasticScroll::OverscrollType::Real);
 	_scroll->setOverscrollBg(QColor(0, 0, 0, 0));
+	_scroll->setOverscrollEdges(
+		[=] { return historyLoadedAtTop(); },
+		[=] { return historyLoadedAtBottom(); });
 	_scroll->geometryChanged(
 	) | rpl::on_next(crl::guard(_list, [=] {
 		_list->onParentGeometryChanged();
 	}), lifetime());
 
-	_scroll->addContentRequests(
-	) | rpl::on_next([=] {
-		if (_history && _history->loadedAtBottom()) {
-			using Result = Data::SponsoredMessages::AppendResult;
-			const auto tryToAppend = [=] {
-				const auto sponsored = &session().sponsoredMessages();
-				const auto result = sponsored->append(_history);
-				if (result == Result::Appended) {
-					_scroll->contentAdded();
-				}
-				return result;
-			};
-			if (tryToAppend() == Result::MediaLoading
-				&& !_historySponsoredPreloading) {
-				session().downloaderTaskFinished(
-				) | rpl::on_next([=] {
-					if (tryToAppend() != Result::MediaLoading) {
-						_historySponsoredPreloading.destroy();
-					}
-				}, _historySponsoredPreloading);
-			}
+	_scroll->setBottomContentRequest([=] {
+		if (!_history || !_history->loadedAtBottom()) {
+			return false;
 		}
-	}, lifetime());
+		using Result = Data::SponsoredMessages::AppendResult;
+		const auto tryToAppend = [=] {
+			return session().sponsoredMessages().append(_history);
+		};
+		const auto result = tryToAppend();
+		if (result == Result::MediaLoading
+			&& !_historySponsoredPreloading) {
+			session().downloaderTaskFinished(
+			) | rpl::on_next([=] {
+				if (tryToAppend() != Result::MediaLoading) {
+					_historySponsoredPreloading.destroy();
+				}
+			}, _historySponsoredPreloading);
+		}
+		return (result == Result::Appended);
+	});
 
 	_fieldBarCancel->addClickHandler([=] { cancelFieldAreaState(); });
 	_send->addClickHandler([=] { sendButtonClicked(); });
@@ -3260,18 +3259,13 @@ void HistoryWidget::showHistory(
 		showAboutTopPromotion();
 
 		if (!session().sponsoredMessages().isTopBarFor(_history)) {
-			_scroll->setTrackingContent(false);
 			const auto checkState = [=] {
 				using State = Data::SponsoredMessages::State;
 				const auto state = session().sponsoredMessages().state(
 					_history);
 				_sponsoredMessagesStateKnown = (state != State::None);
-				if (state == State::AppendToEnd) {
-					_scroll->setTrackingContent(
-						session().sponsoredMessages().canHaveFor(_history));
-				} else if (state == State::InjectToMiddle) {
+				if (state == State::InjectToMiddle) {
 					injectSponsoredMessages();
-				} else if (state == State::AppendToTopBar) {
 				}
 			};
 			const auto history = _history;

Telegram/SourceFiles/history/history_widget.h

@@ -83,7 +83,7 @@ class SendFilesWay;
 class SendAsButton;
 class SpoilerAnimation;
 class ChooseThemeController;
-class ContinuousScroll;
+class ElasticScroll;
 struct ChatPaintHighlight;
 class ChatStyle;
 template <typename Widget>
@@ -854,7 +854,7 @@ private:
 	int _supportPreloadRequest = 0; // Not real mtpRequestId.
 
 	object_ptr<HistoryView::TopBarWidget> _topBar;
-	object_ptr<Ui::ContinuousScroll> _scroll;
+	object_ptr<Ui::ElasticScroll> _scroll;
 	QPointer<HistoryInner> _list;
 	History *_migrated = nullptr;
 	History *_history = nullptr;

Telegram/SourceFiles/ui/chat/continuous_scroll.cpp

@@ -1,56 +0,0 @@
-/*
-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
-*/
-#include "ui/chat/continuous_scroll.h"
-
-#include <QWheelEvent>
-#include <QKeyEvent>
-
-namespace Ui {
-
-ContinuousScroll::ContinuousScroll(
-	QWidget *parent,
-	const style::ScrollArea &st,
-	Qt::Orientation orientation)
-: ElasticScroll(parent, st, orientation) {
-	setCustomWheelProcess([=](not_null<QWheelEvent*> e) {
-		if (_tracking
-			&& !e->angleDelta().isNull()
-			&& (e->angleDelta().y() < 0)
-			&& (scrollTopMax() == scrollTop())) {
-			_addContentRequests.fire({});
-			// Carry into freshly appended content, else swallow the over-scroll.
-			return !base::take(_contentAdded);
-		}
-		return false;
-	});
-}
-
-void ContinuousScroll::keyPressEvent(QKeyEvent *e) {
-	const auto key = e->key();
-	if (_tracking
-		&& (key == Qt::Key_Down || key == Qt::Key_PageDown)
-		&& (scrollTopMax() == scrollTop())) {
-		_addContentRequests.fire({});
-		base::take(_contentAdded);
-	}
-	ElasticScroll::keyPressEvent(e);
-}
-
-void ContinuousScroll::setTrackingContent(bool value) {
-	_tracking = value;
-}
-
-void ContinuousScroll::contentAdded() {
-	_contentAdded = true;
-}
-
-rpl::producer<> ContinuousScroll::addContentRequests() const {
-	return _addContentRequests.events();
-}
-
-} // namespace Ui

Telegram/SourceFiles/ui/chat/continuous_scroll.h

@@ -1,38 +0,0 @@
-/*
-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/elastic_scroll.h"
-
-namespace Ui {
-
-// This class is designed for seamless scrolling of
-// on-demand augmented content.
-class ContinuousScroll final : public ElasticScroll {
-public:
-	ContinuousScroll(
-		QWidget *parent,
-		const style::ScrollArea &st = st::defaultScrollArea,
-		Qt::Orientation orientation = Qt::Vertical);
-
-	void keyPressEvent(QKeyEvent *e) override;
-
-	[[nodiscard]] rpl::producer<> addContentRequests() const;
-	void contentAdded();
-
-	void setTrackingContent(bool value);
-
-private:
-	bool _contentAdded = false;
-	bool _tracking = false;
-
-	rpl::event_stream<> _addContentRequests;
-
-};
-
-} // namespace Ui

Telegram/cmake/td_ui.cmake

@@ -398,8 +398,6 @@ PRIVATE
     ui/chat/chat_theme.h
     ui/chat/chats_filter_tag.cpp
     ui/chat/chats_filter_tag.h
-    ui/chat/continuous_scroll.cpp
-    ui/chat/continuous_scroll.h
     ui/chat/forward_options_box.cpp
     ui/chat/forward_options_box.h
     ui/chat/group_call_bar.cpp