Fix shift-click selection on macOS

PR #22284.
Closes #16818.

src/gui/CMakeLists.txt

@@ -287,6 +287,8 @@ if (CMAKE_SYSTEM_NAME STREQUAL "Darwin")
         macosdockbadge/badger.mm
         macosdockbadge/badgeview.h
         macosdockbadge/badgeview.mm
+        macosshiftclickhandler.h
+        macosshiftclickhandler.cpp
         macutilities.h
         macutilities.mm
     )

src/gui/macosshiftclickhandler.cpp

@@ -0,0 +1,73 @@
+/*
+ * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2025  Luke Memet (lukemmtt)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ */
+
+#include "macosshiftclickhandler.h"
+
+#include <QMouseEvent>
+#include <QTreeView>
+
+MacOSShiftClickHandler::MacOSShiftClickHandler(QTreeView *treeView)
+    : QObject(treeView)
+    , m_treeView {treeView}
+{
+    treeView->installEventFilter(this);
+}
+
+bool MacOSShiftClickHandler::eventFilter(QObject *watched, QEvent *event)
+{
+    if ((watched == m_treeView) && (event->type() == QEvent::MouseButtonPress))
+    {
+        const auto *mouseEvent = static_cast<QMouseEvent *>(event);
+        if (mouseEvent->button() != Qt::LeftButton)
+            return false;
+
+        const QModelIndex clickedIndex = m_treeView->indexAt(mouseEvent->position().toPoint());
+        if (!clickedIndex.isValid())
+            return false;
+
+        const Qt::KeyboardModifiers modifiers = mouseEvent->modifiers();
+        const bool shiftPressed = modifiers.testFlag(Qt::ShiftModifier);
+
+        if (shiftPressed && m_lastClickedIndex.isValid())
+        {
+            const QItemSelection selection(m_lastClickedIndex, clickedIndex);
+            const bool commandPressed = modifiers.testFlag(Qt::ControlModifier);
+            if (commandPressed)
+                m_treeView->selectionModel()->select(selection, (QItemSelectionModel::Select | QItemSelectionModel::Rows));
+            else
+                m_treeView->selectionModel()->select(selection, (QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows));
+            m_treeView->selectionModel()->setCurrentIndex(clickedIndex, QItemSelectionModel::NoUpdate);
+            return true;
+        }
+
+        if (!modifiers.testFlags(Qt::AltModifier | Qt::MetaModifier))
+            m_lastClickedIndex = clickedIndex;
+    }
+
+    return QObject::eventFilter(watched, event);
+}

src/gui/macosshiftclickhandler.h

@@ -0,0 +1,50 @@
+/*
+ * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2025  Luke Memet (lukemmtt)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ */
+
+#pragma once
+
+#include <QObject>
+#include <QPersistentModelIndex>
+
+class QTreeView;
+
+// Workaround for QTBUG-115838: Shift-click range selection not working properly on macOS
+class MacOSShiftClickHandler final : public QObject
+{
+    Q_OBJECT
+    Q_DISABLE_COPY_MOVE(MacOSShiftClickHandler)
+
+public:
+    explicit MacOSShiftClickHandler(QTreeView *treeView);
+
+private:
+    bool eventFilter(QObject *watched, QEvent *event) override;
+
+    QTreeView *m_treeView = nullptr;
+    QPersistentModelIndex m_lastClickedIndex;
+};

src/gui/transferlistwidget.cpp

@@ -74,6 +74,7 @@
 #include "utils.h"
 
 #ifdef Q_OS_MACOS
+#include "macosshiftclickhandler.h"
 #include "macutilities.h"
 #endif
 
@@ -158,6 +159,7 @@ TransferListWidget::TransferListWidget(IGUIApplication *app, QWidget *parent)
     setDropIndicatorShown(true);
 #if defined(Q_OS_MACOS)
     setAttribute(Qt::WA_MacShowFocusRect, false);
+    new MacOSShiftClickHandler(this);
 #endif
     header()->setFirstSectionMovable(true);
     header()->setStretchLastSection(false);