From d27e4803a130a262b84a54c915fc83f8c9bbe2f4 Mon Sep 17 00:00:00 2001
From: 23rd <23rd@vivaldi.net>
Date: Mon, 14 Mar 2022 17:39:02 +0300
Subject: [PATCH] Moved base::Timer to std::unique_ptr in
 DraggingScrollManager.

---
 ui/dragging_scroll_manager.cpp | 21 +++++++++++++--------
 ui/dragging_scroll_manager.h   | 10 +++++-----
 2 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/ui/dragging_scroll_manager.cpp b/ui/dragging_scroll_manager.cpp
index 5df4ee5..29aecdf 100644
--- a/ui/dragging_scroll_manager.cpp
+++ b/ui/dragging_scroll_manager.cpp
@@ -7,13 +7,12 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #include "ui/dragging_scroll_manager.h"
 
-#include "ui/widgets/scroll_area.h"
+#include "base/timer.h"
+#include "ui/widgets/scroll_area.h" // kMaxScrollSpeed.
 
 namespace Ui {
 
-DraggingScrollManager::DraggingScrollManager()
-: _timer([=] { scrollByTimer(); }) {
-}
+DraggingScrollManager::DraggingScrollManager() = default;
 
 void DraggingScrollManager::scrollByTimer() {
 	const auto d = (_delta > 0)
@@ -25,9 +24,12 @@ void DraggingScrollManager::scrollByTimer() {
 void DraggingScrollManager::checkDeltaScroll(int delta) {
 	_delta = delta;
 	if (_delta) {
-		_timer.callEach(15);
+		if (!_timer) {
+			_timer = std::make_unique<base::Timer>([=] { scrollByTimer(); });
+		}
+		_timer->callEach(15);
 	} else {
-		_timer.cancel();
+		cancel();
 	}
 }
 
@@ -44,10 +46,13 @@ void DraggingScrollManager::checkDeltaScroll(
 }
 
 void DraggingScrollManager::cancel() {
-	_timer.cancel();
+	if (_timer) {
+		_timer->cancel();
+		_timer = nullptr;
+	}
 }
 
-rpl::producer<int> DraggingScrollManager::scrolls() {
+rpl::producer<int> DraggingScrollManager::scrolls() const {
 	return _scrolls.events();
 }
 
diff --git a/ui/dragging_scroll_manager.h b/ui/dragging_scroll_manager.h
index 0d73b95..5ae4f1b 100644
--- a/ui/dragging_scroll_manager.h
+++ b/ui/dragging_scroll_manager.h
@@ -7,12 +7,12 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 */
 #pragma once
 
-#include "base/timer.h"
+namespace base {
+class Timer;
+} // namespace base
 
 namespace Ui {
 
-class ScrollArea;
-
 class DraggingScrollManager final {
 public:
 	DraggingScrollManager();
@@ -21,12 +21,12 @@ public:
 	void checkDeltaScroll(const QPoint &point, int top, int bottom);
 	void cancel();
 
-	rpl::producer<int> scrolls();
+	[[nodiscard]] rpl::producer<int> scrolls() const;
 
 private:
 	void scrollByTimer();
 
-	base::Timer _timer;
+	std::unique_ptr<base::Timer> _timer;
 	int _delta = 0;
 	rpl::event_stream<int> _scrolls;