Fix glitch in Settings > Premium layer scroll-to-bottom.

Telegram/SourceFiles/info/info_content_widget.h

@@ -113,7 +113,7 @@ private:
 
 	style::color _bg;
 	rpl::variable<int> _scrollTopSkip = -1;
-	rpl::variable<int> _scrollBottomSkip = -1;
+	rpl::variable<int> _scrollBottomSkip = 0;
 	rpl::event_stream<int> _scrollTillBottomChanges;
 	object_ptr<Ui::ScrollArea> _scroll;
 	Ui::PaddingWrap<Ui::RpWidget> *_innerWrap = nullptr;

Telegram/SourceFiles/info/info_layer_widget.cpp

@@ -299,9 +299,13 @@ QRect LayerWidget::countGeometry(int newWidth) {
 	contentHeight += additionalScroll;
 	_tillBottom = (newTop + desiredHeight >= windowHeight);
 	if (_tillBottom) {
-		contentHeight += contentBottom;
 		additionalScroll += contentBottom;
 	}
+	_contentTillBottom = _tillBottom && !_content->scrollBottomSkip();
+	if (_contentTillBottom) {
+		contentHeight += contentBottom;
+	}
+	const auto bottomPadding = _tillBottom ? 0 : contentBottom;
 	_content->updateGeometry({
 		contentLeft,
 		contentTop,
@@ -328,6 +332,8 @@ void LayerWidget::paintEvent(QPaintEvent *e) {
 		if (clip.intersects({ 0, height() - radius, width(), radius })) {
 			parts |= RectPart::FullBottom;
 		}
+	} else if (!_contentTillBottom) {
+		p.fillRect(0, height() - radius, width(), radius, st::boxBg);
 	}
 	if (_content->animatingShow()) {
 		if (clip.intersects({ 0, 0, width(), radius })) {

Telegram/SourceFiles/info/info_layer_widget.h

@@ -83,6 +83,7 @@ private:
 	bool _inResize = false;
 	bool _pendingResize = false;
 	bool _tillBottom = false;
+	bool _contentTillBottom = false;
 
 	bool _floatPlayerDelegateRestored = false;
 

Telegram/SourceFiles/info/info_section_widget.cpp

@@ -16,6 +16,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "info/info_layer_widget.h"
 #include "info/info_memento.h"
 #include "info/info_controller.h"
+#include "styles/style_layers.h"
 
 namespace Info {
 
@@ -42,11 +43,15 @@ SectionWidget::SectionWidget(
 void SectionWidget::init() {
 	Expects(_connecting == nullptr);
 
-	sizeValue(
-	) | rpl::start_with_next([wrap = _content.data()](QSize size) {
+	rpl::combine(
+		sizeValue(),
+		_content->desiredHeightValue()
+	) | rpl::start_with_next([wrap = _content.data()](QSize size, int) {
 		const auto expanding = false;
-		auto wrapGeometry = QRect{ { 0, 0 }, size };
-		auto additionalScroll = 0;
+		const auto additionalScroll = st::boxRadius;
+		const auto full = !wrap->scrollBottomSkip();
+		const auto height = size.height() - (full ? 0 : st::boxRadius);
+		const auto wrapGeometry = QRect{ 0, 0, size.width(), height };
 		wrap->updateGeometry(wrapGeometry, expanding, additionalScroll);
 	}, _content->lifetime());
 
@@ -88,6 +93,13 @@ void SectionWidget::showAnimatedHook(
 	_topBarSurrogate = _content->createTopBarSurrogate(this);
 }
 
+void SectionWidget::paintEvent(QPaintEvent *e) {
+	Window::SectionWidget::paintEvent(e);
+	if (!animatingShow()) {
+		QPainter(this).fillRect(e->rect(), st::windowBg);
+	}
+}
+
 bool SectionWidget::showInternal(
 		not_null<Window::SectionMemento*> memento,
 		const Window::SectionShow &params) {

Telegram/SourceFiles/info/info_section_widget.h

@@ -63,6 +63,7 @@ protected:
 
 	void showAnimatedHook(
 		const Window::SectionSlideParams &params) override;
+	void paintEvent(QPaintEvent *e) override;
 
 private:
 	void init();

Telegram/SourceFiles/info/info_wrap_widget.cpp

@@ -645,8 +645,8 @@ void WrapWidget::showContent(object_ptr<ContentWidget> content) {
 		old->setParent(nullptr);
 		old.destroy();
 	}
-	_content->show();
 	_additionalScroll = 0;
+	_content->show();
 	//_anotherTabMemento = nullptr;
 	finishShowContent();
 }
@@ -1098,6 +1098,10 @@ int WrapWidget::scrollTillBottom(int forHeight) const {
 	return _content->scrollTillBottom(forHeight - topWidget()->height());
 }
 
+int WrapWidget::scrollBottomSkip() const {
+	return _content->scrollBottomSkip();
+}
+
 rpl::producer<int> WrapWidget::scrollTillBottomChanges() const {
 	return _scrollTillBottomChanges.events_starting_with(
 		_content->scrollTillBottomChanges()

Telegram/SourceFiles/info/info_wrap_widget.h

@@ -125,6 +125,7 @@ public:
 		QRect newGeometry,
 		bool expanding,
 		int additionalScroll);
+	[[nodiscard]] int scrollBottomSkip() const;
 	[[nodiscard]] int scrollTillBottom(int forHeight) const;
 	[[nodiscard]] rpl::producer<int> scrollTillBottomChanges() const;
 	[[nodiscard]] rpl::producer<bool> grabbingForExpanding() const;

Telegram/SourceFiles/settings/settings.style

@@ -422,5 +422,5 @@ notifyPreviewChecksSkip: 12px;
 notifyPreviewBottomSkip: 9px;
 
 settingsPremiumDescriptionSkip: 3px;
-settingsPremiumButtonPadding: margins(11px, 11px, 11px, 11px);
+settingsPremiumButtonPadding: margins(11px, 11px, 11px, 3px);
 

Telegram/SourceFiles/settings/settings_premium.cpp

@@ -12,7 +12,9 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "settings/settings_premium.h"
 #include "core/application.h"
 #include "ui/abstract_button.h"
+#include "ui/basic_click_handlers.h"
 #include "ui/effects/gradient.h"
+#include "ui/effects/premium_graphics.h"
 #include "ui/text/text_utilities.h"
 #include "ui/widgets/gradient_round_button.h"
 #include "ui/widgets/labels.h"
@@ -21,6 +23,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "window/window_session_controller.h"
 #include "window/window_controller.h"
 #include "main/main_session.h"
+#include "main/main_account.h"
+#include "main/main_app_config.h"
 #include "styles/style_boxes.h"
 #include "styles/style_chat_helpers.h"
 #include "styles/style_layers.h"
@@ -41,22 +45,25 @@ public:
 		not_null<Ui::RpWidget*> parent) override;
 
 private:
-	void setupContent(not_null<Window::SessionController*> controller);
+	void setupContent();
+
+	const not_null<Window::SessionController*> _controller;
 
 };
 
 Premium::Premium(
 	QWidget *parent,
 	not_null<Window::SessionController*> controller)
-: Section(parent) {
-	setupContent(controller);
+: Section(parent)
+, _controller(controller) {
+	setupContent();
 }
 
 rpl::producer<QString> Premium::title() {
 	return tr::lng_premium_summary_title();
 }
 
-void Premium::setupContent(not_null<Window::SessionController*> controller) {
+void Premium::setupContent() {
 	const auto content = Ui::CreateChild<Ui::VerticalLayout>(this);
 
 	content->add(
@@ -221,11 +228,11 @@ QPointer<Ui::RpWidget> Premium::createPinnedToBottom(
 
 	auto result = object_ptr<Ui::GradientButton>(
 		content,
-		QGradientStops{
-			{ 0., st::premiumButtonBg1->c },
-			{ .6, st::premiumButtonBg2->c },
-			{ 1., st::premiumButtonBg3->c },
-		});
+		Ui::Premium::ButtonGradientStops());
+
+	result->setClickedCallback([=] {
+		StartPremiumPayment(_controller, "settings");
+	});
 
 	const auto &st = st::premiumPreviewBox.button;
 	result->resize(content->width(), st.height);
@@ -271,4 +278,21 @@ void ShowPremium(not_null<Main::Session*> session) {
 	}
 }
 
+void StartPremiumPayment(
+		not_null<Window::SessionController*> controller,
+		const QString &ref) {
+	const auto account = &controller->session().account();
+	const auto username = account->appConfig().get<QString>(
+		"premium_bot_username",
+		QString());
+	const auto slug = account->appConfig().get<QString>(
+		"premium_invoice_slug",
+		QString());
+	if (!username.isEmpty()) {
+		UrlClickHandler::Open("https://t.me/" + username + "?start=" + ref);
+	} else if (!slug.isEmpty()) {
+		UrlClickHandler::Open("https://t.me/$" + slug);
+	}
+}
+
 } // namespace Settings

Telegram/SourceFiles/settings/settings_premium.h

@@ -13,11 +13,18 @@ namespace Main {
 class Session;
 } // namespace Main
 
+namespace Window {
+class SessionController;
+} // namespace Window
+
 namespace Settings {
 
 [[nodiscard]] Type PremiumId();
 
 void ShowPremium(not_null<::Main::Session*> session);
+void StartPremiumPayment(
+	not_null<Window::SessionController*> controller,
+	const QString &ref);
 
 } // namespace Settings