Empty preview widget on long userpic press.

Telegram/SourceFiles/dialogs/dialogs_inner_widget.cpp

@@ -15,6 +15,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "dialogs/dialogs_widget.h"
 #include "dialogs/dialogs_search_from_controllers.h"
 #include "dialogs/dialogs_search_tags.h"
+#include "history/view/history_view_chat_preview.h"
 #include "history/view/history_view_context_menu.h"
 #include "history/history.h"
 #include "history/history_item.h"
@@ -80,6 +81,7 @@ namespace {
 
 constexpr auto kHashtagResultsLimit = 5;
 constexpr auto kStartReorderThreshold = 30;
+constexpr auto kChatPreviewDelay = crl::time(1000);
 
 int FixedOnTopDialogsCount(not_null<Dialogs::IndexedList*> list) {
 	auto result = 0;
@@ -157,6 +159,7 @@ InnerWidget::InnerWidget(
 	+ st::defaultDialogRow.padding.left())
 , _cancelSearchInChat(this, st::dialogsCancelSearchInPeer)
 , _cancelSearchFromUser(this, st::dialogsCancelSearchInPeer)
+, _chatPreviewTimer([=] { showChatPreview(); })
 , _childListShown(std::move(childListShown)) {
 	setAttribute(Qt::WA_OpaquePaintEvent, true);
 
@@ -651,6 +654,8 @@ void InnerWidget::paintEvent(QPaintEvent *e) {
 		context.active = active;
 		context.selected = _menuRow.key
 			? (row->key() == _menuRow.key)
+			: _chatPreviewKey
+			? (row->key() == _chatPreviewKey)
 			: selected;
 		context.topicJumpSelected = selected
 			&& _selectedTopicJump
@@ -1268,6 +1273,14 @@ void InnerWidget::mouseMoveEvent(QMouseEvent *e) {
 		return;
 	}
 	selectByMouse(globalPosition);
+	if (!isUserpicPress()) {
+		cancelChatPreview();
+	}
+}
+
+void InnerWidget::cancelChatPreview() {
+	_chatPreviewTimer.cancel();
+	_chatPreviewWillBeFor = {};
 }
 
 void InnerWidget::clearIrrelevantState() {
@@ -1490,11 +1503,15 @@ void InnerWidget::mousePressEvent(QMouseEvent *e) {
 			row->repaint());
 	}
 	ClickHandler::pressed();
-	if (anim::Disabled()
+	if (pressShowsPreview()) {
+		_chatPreviewWillBeFor = computeChosenRow().key;
+		_chatPreviewTimer.callOnce(kChatPreviewDelay);
+	} else if (anim::Disabled()
 		&& (!_pressed || !_pressed->entry()->isPinnedDialog(_filterId))) {
 		mousePressReleased(e->globalPos(), e->button(), e->modifiers());
 	}
 }
+
 const std::vector<Key> &InnerWidget::pinnedChatsOrder() const {
 	const auto owner = &session().data();
 	return _savedSublists
@@ -1513,6 +1530,7 @@ void InnerWidget::checkReorderPinnedStart(QPoint localPosition) {
 		< style::ConvertScale(kStartReorderThreshold)) {
 		return;
 	}
+	cancelChatPreview();
 	_dragging = _pressed;
 	if (updateReorderIndexGetCount() < 2) {
 		_dragging = nullptr;
@@ -2288,6 +2306,33 @@ void InnerWidget::fillArchiveSearchMenu(not_null<Ui::PopupMenu*> menu) {
 	});
 }
 
+void InnerWidget::showChatPreview() {
+	const auto key = base::take(_chatPreviewWillBeFor);
+	cancelChatPreview();
+	if (!pressShowsPreview() || key != computeChosenRow().key) {
+		return;
+	}
+	ClickHandler::unpressed();
+	mousePressReleased(QCursor::pos(), Qt::NoButton, Qt::NoModifier);
+
+	_chatPreviewKey = key;
+	_menu = HistoryView::MakeChatPreview(this, key.entry());
+	if (!_menu) {
+		return;
+	}
+	QObject::connect(_menu.get(), &QObject::destroyed, [=] {
+		if (_chatPreviewKey) {
+			updateDialogRow(RowDescriptor(base::take(_chatPreviewKey), {}));
+		}
+		const auto globalPosition = QCursor::pos();
+		if (rect().contains(mapFromGlobal(globalPosition))) {
+			setMouseTracking(true);
+			selectByMouse(globalPosition);
+		}
+	});
+	_menu->popup(_lastMousePosition.value_or(QCursor::pos()));
+}
+
 void InnerWidget::contextMenuEvent(QContextMenuEvent *e) {
 	_menu = nullptr;
 
@@ -2316,7 +2361,9 @@ void InnerWidget::contextMenuEvent(QContextMenuEvent *e) {
 		}
 		return RowDescriptor();
 	}();
-	if (!row.key) return;
+	if (!row.key) {
+		return;
+	}
 
 	_menuRow = row;
 	if (_pressButton != Qt::LeftButton) {
@@ -2555,6 +2602,12 @@ void InnerWidget::trackSearchResultsHistory(not_null<History*> history) {
 				refresh();
 				clearMouseSelection(true);
 			}
+			if (_chatPreviewWillBeFor.topic() == topic) {
+				_chatPreviewWillBeFor = {};
+			}
+			if (_chatPreviewKey.topic() == topic) {
+				_chatPreviewKey = {};
+			}
 		}, _searchResultsLifetime);
 	}
 }
@@ -3499,6 +3552,23 @@ ChosenRow InnerWidget::computeChosenRow() const {
 	return ChosenRow();
 }
 
+bool InnerWidget::isUserpicPress() const {
+	return  (_lastRowLocalMouseX >= 0)
+		&& (_lastRowLocalMouseX < _st->nameLeft)
+		&& (width() > _narrowWidth);
+}
+
+bool InnerWidget::pressShowsPreview() const {
+	if (!isUserpicPress()) {
+		return false;
+	}
+	const auto key = computeChosenRow().key;
+	if (const auto history = key.history()) {
+		return !history->peer->isForum();
+	}
+	return key.topic() != nullptr;;
+}
+
 bool InnerWidget::chooseRow(
 		Qt::KeyboardModifiers modifiers,
 		MsgId pressedTopicRootId) {
@@ -3511,9 +3581,7 @@ bool InnerWidget::chooseRow(
 			ChosenRow row,
 			Qt::KeyboardModifiers modifiers) {
 		row.newWindow = (modifiers & Qt::ControlModifier);
-		row.userpicClick = (_lastRowLocalMouseX >= 0)
-			&& (_lastRowLocalMouseX < _st->nameLeft)
-			&& (width() > _narrowWidth);
+		row.userpicClick = isUserpicPress();
 		return row;
 	};
 	auto chosen = modifyChosenRow(computeChosenRow(), modifiers);