Initial work on porting to Qt6

- CMake updates to require Qt 6, and use the unversioned target / command names to simplify future porting
- Remove ifdefs for supporting old Qt5 version
- Replace QStandardPaths::DataLocation with the recommended AppDataLocation
- Port to QRegularExpression
- Replace QFontMetrics::width() with horizontalAdvance()
- Many updates to music symbol handling now that we can't implicitly convert to QChar
- Only tested on macOS so far

.github/workflows/build.yml

@@ -49,9 +49,9 @@ jobs:
         rm /usr/local/bin/idle3*
         rm /usr/local/bin/pydoc3*
         rm /usr/local/bin/python3*
-        brew install --overwrite boost cmake doctest minizip ninja nlohmann-json pugixml qt5 pugixml rtmidi
+        brew install --overwrite boost cmake doctest minizip ninja nlohmann-json pugixml qt6 pugixml rtmidi
     - name: Generate Project
-      run: cmake -S ${GITHUB_WORKSPACE} -B ${{runner.workspace}}/build -G Ninja -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=/usr/local/opt/qt@5/lib/cmake
+      run: cmake -S ${GITHUB_WORKSPACE} -B ${{runner.workspace}}/build -G Ninja -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=/usr/local/opt/qt6/lib/cmake
     - name: Build
       run: cmake --build ${{runner.workspace}}/build
     - name: Test

CHANGELOG.md

@@ -21,6 +21,7 @@ Thanks to the following contributors who worked on this release:
 - Chord diagrams now display the fret number of the top fret instead of the next fret after it (#408)
 - Updated the minimum required version of `RtMidi` to 4.0
 - Updated the minimum required version of `boost` to 1.74
+- Updated the minimum required version of `Qt` to 6.2
 
 ### Fixed
 - Fixed a bug that caused some preferences such as custom shortcuts to not persist on macOS. Note that all other preferences (such as MIDI settings) are reset by this fix and will need to be manually changed to the desired values (#447).

README.md

@@ -76,7 +76,7 @@ Power Tab Editor 2.0 - A powerful cross platform guitar tablature viewer and edi
   * rational
   * signals2
   * stacktrace
-* [Qt](http://qt-project.org/) >= 5.10 version or greater
+* [Qt](http://qt-project.org/) >= 6.2 version or greater
 * [nlohmann-json](https://github.com/nlohmann/json) >= 3.7.3
 * [RtMidi](https://www.music.mcgill.ca/~gary/rtmidi/) >= 4.0
 * [pugixml](https://pugixml.org/)
@@ -129,10 +129,10 @@ You'll have to update the variables for your specific paths to `$vcpkg_exe_path`
 #### OS X:
 * Install Xcode along with its Command Line Tools.
 * Install dependencies:
-  * `brew install boost cmake doctest minizip ninja nlohmann-json pugixml qt@5 pugixml rtmidi`
+  * `brew install boost cmake doctest minizip ninja nlohmann-json pugixml qt6 pugixml rtmidi`
 * Build:
   * `mkdir build && cd build`
-  * `cmake -G Ninja -DCMAKE_BUILD_TYPE=Debug -DCMAKE_PREFIX_PATH=/usr/local/opt/qt@5/lib/cmake ..`
+  * `cmake -G Ninja -DCMAKE_BUILD_TYPE=Debug -DCMAKE_PREFIX_PATH=/usr/local/opt/qt6/lib/cmake ..`
     * To generate an Xcode project, switch to `-G Xcode` and then open and build `build/powertabeditor.xcodeproj`
   * `ninja`
 * Run:

cmake/PTE_Executable.cmake

@@ -10,7 +10,7 @@ function( pte_executable )
 
     set( generated_files )
     if ( PTE_EXE_RESOURCES )
-        qt5_add_resources( generated_files ${PTE_EXE_RESOURCES} )
+        qt_add_resources( generated_files ${PTE_EXE_RESOURCES} )
     endif ()
 
     if ( PTE_EXE_CONSOLE )

cmake/PTE_Library.cmake

@@ -10,10 +10,10 @@ function( pte_library )
     set( generated_headers )
     set( moc_files )
     if ( PTE_LIB_FORMS )
-        qt5_wrap_ui( generated_headers ${PTE_LIB_FORMS} )
+        qt_wrap_ui( generated_headers ${PTE_LIB_FORMS} )
     endif ()
     if ( PTE_LIB_MOC_HEADERS )
-        qt5_wrap_cpp( moc_files ${PTE_LIB_MOC_HEADERS} )
+        qt_wrap_cpp( moc_files ${PTE_LIB_MOC_HEADERS} )
     endif ()
 
     add_library( ${PTE_LIB_NAME} STATIC

cmake/third_party/Qt.cmake

@@ -1,18 +1,20 @@
-find_package( Qt5Widgets REQUIRED )
-find_package( Qt5Network REQUIRED )
-find_package( Qt5PrintSupport REQUIRED )
-find_package( Qt5LinguistTools REQUIRED )
+find_package( Qt6 REQUIRED COMPONENTS
+	Widgets
+	Network
+	PrintSupport
+	LinguistTools
+)
 
-set( QT5_PLUGINS )
+set( QT_PLUGINS )
 if ( PLATFORM_WIN )
-	set( QT5_PLUGINS 
-        Qt5::QWindowsIntegrationPlugin
-        Qt5::QWindowsVistaStylePlugin
+	set( QT_PLUGINS 
+        Qt::QWindowsIntegrationPlugin
+        Qt::QWindowsVistaStylePlugin
     )
 endif ()
 
 # Find some standard paths to the Qt installation.
-get_target_property( _uic_path Qt5::uic IMPORTED_LOCATION )
+get_target_property( _uic_path Qt::lconvert IMPORTED_LOCATION )
 get_filename_component( PTE_QT_BIN_DIR ${_uic_path} DIRECTORY )
 get_filename_component( PTE_QT_ROOT_DIR ${PTE_QT_BIN_DIR} DIRECTORY )
 

source/actions/CMakeLists.txt

@@ -127,5 +127,5 @@ pte_library(
     MOC_HEADERS ${moc_headers}
     DEPENDS
         ptescore
-        Qt5::Widgets
+        Qt::Widgets
 )

source/app/CMakeLists.txt

@@ -53,6 +53,6 @@ pte_library(
         ptepainters
         ptewidgets
         pteutil
-        Qt5::Widgets
-        Qt5::PrintSupport
+        Qt::Widgets
+        Qt::PrintSupport
 )

source/app/paths.cpp

@@ -42,14 +42,14 @@ path getConfigDir()
 path getUserDataDir()
 {
     return fromQString(
-        QStandardPaths::writableLocation(QStandardPaths::DataLocation));
+        QStandardPaths::writableLocation(QStandardPaths::AppDataLocation));
 }
 
 std::vector<path> getDataDirs()
 {
     std::vector<path> paths;
     for (const QString &p :
-         QStandardPaths::standardLocations(QStandardPaths::DataLocation))
+         QStandardPaths::standardLocations(QStandardPaths::AppDataLocation))
     {
         paths.push_back(fromQString(p));
     }
@@ -67,8 +67,7 @@ getTranslationDirs()
         p /= "translations";
 
     // Also check in the Qt translations folder.
-    paths.push_back(
-        fromQString(QLibraryInfo::location(QLibraryInfo::TranslationsPath)));
+    paths.push_back(fromQString(QLibraryInfo::path(QLibraryInfo::TranslationsPath)));
 
     return paths;
 }

source/app/powertabeditor.cpp

@@ -125,6 +125,7 @@
 
 #include <formats/fileformatmanager.h>
 
+#include <QActionGroup>
 #include <QCoreApplication>
 #include <QDebug>
 #include <QDesktopServices>
@@ -138,6 +139,7 @@
 #include <QPrinter>
 #include <QPrintDialog>
 #include <QPrintPreviewDialog>
+#include <QRegularExpression>
 #include <QScrollArea>
 #include <QTabBar>
 #include <QUrl>
@@ -457,11 +459,12 @@ bool PowerTabEditor::saveFileAs(int doc_index)
         if (info.suffix().isEmpty())
         {
             const QString file_filter = dialog.selectedNameFilter();
-            QRegExp regex("\\*.(\\w+)");
-            if (regex.indexIn(file_filter, 0) < 0)
+            QRegularExpression regex("\\*.(\\w+)");
+            QRegularExpressionMatch match = regex.match(file_filter);
+            if (!match.hasMatch())
                 return false;
 
-            const QString extension = regex.cap(1);
+            const QString extension = match.captured(1);
             path += ".";
             path += extension;
         }
@@ -2207,14 +2210,6 @@ void PowerTabEditor::updateWindowTitle()
     setWindowTitle(name);
 }
 
-/// C++20 deprecated bitwise operations between different enum types, which
-/// QKeySequence relies on.
-inline constexpr int
-operator|(Qt::Modifier m, Qt::Key k)
-{
-    return static_cast<int>(m) | static_cast<int>(k);
-}
-
 void PowerTabEditor::createCommands()
 {
     // File-related commands.
@@ -3596,7 +3591,7 @@ void PowerTabEditor::createTabArea()
     QVBoxLayout *layout = new QVBoxLayout(myPlaybackArea);
     layout->addWidget(myTabWidget);
     layout->addWidget(myPlaybackWidget, 0, Qt::AlignHCenter);
-    layout->setMargin(0);
+    layout->setContentsMargins(0, 0, 0, 0);
     layout->setSpacing(0);
 
     enableEditing(false);
@@ -3759,11 +3754,7 @@ void PowerTabEditor::setupNewTab()
     // Each tab is 200px wide, so we want to shorten the name if it's wider
     // than 140px.
     bool chopped = false;
-#if (QT_VERSION >= QT_VERSION_CHECK(5,11,0))
     while (fm.horizontalAdvance(title) > 140)
-#else
-    while (fm.width(title) > 140)
-#endif
     {
         title.chop(1);
         chopped = true;

source/audio/CMakeLists.txt

@@ -43,7 +43,7 @@ pte_library(
     DEPENDS
         PUBLIC
             ptescore
-            Qt5::Core
+            Qt::Core
         PRIVATE
             rtmidi::rtmidi
             ${platform_deps}

source/build/CMakeLists.txt

@@ -27,11 +27,11 @@ pte_executable(
     DEPENDS
         pteapp
         ptedialogs
-        Qt5::Network
-        Qt5::Widgets
+        Qt::Network
+        Qt::Widgets
         ${platform_deps}
     PLUGINS
-        ${QT5_PLUGINS}
+        ${QT_PLUGINS}
 )
 
 if ( PLATFORM_OSX )

source/build/main.cpp

@@ -46,16 +46,7 @@
 static void displayError(const std::string &reason)
 {
     std::string message = reason;
-#if BOOST_VERSION >= 106900
-    message += boost::stacktrace::to_string(
-        boost::stacktrace::stacktrace());
-#else
-    for (auto &&frame : boost::stacktrace::stacktrace())
-    {
-        message += boost::stacktrace::to_string(frame);
-        message += "\n";
-    }
-#endif
+    message += boost::stacktrace::to_string(boost::stacktrace::stacktrace());
 
     // If there is no QApplication instance, something went seriously wrong
     // during startup - just dump the error to the console.
@@ -147,25 +138,15 @@ loadTranslations(QApplication &app, QTranslator &qt_translator,
             ptb_translator.load(locale, QStringLiteral("powertabeditor"),
                                 QStringLiteral("_"), dir))
         {
-#if (QT_VERSION >= QT_VERSION_CHECK(5,15,0))
-            qDebug() << "Loaded application translations from"
-                     << ptb_translator.filePath();
-#else
-            qDebug() << "Loaded application translations";
-#endif
+            qDebug() << "Loaded application translations from" << ptb_translator.filePath();
             app.installTranslator(&ptb_translator);
         }
 
         if (qt_translator.isEmpty() &&
             qt_translator.load(locale, QStringLiteral("qtbase"),
                                QStringLiteral("_"), dir))
         {
-#if (QT_VERSION >= QT_VERSION_CHECK(5,15,0))
-            qDebug() << "Loaded Qt base translations from"
-                     << qt_translator.filePath();
-#else
-            qDebug() << "Loaded Qt base translations";
-#endif
+            qDebug() << "Loaded Qt base translations from" << qt_translator.filePath();
             app.installTranslator(&qt_translator);
         }
     }

source/dialogs/CMakeLists.txt

@@ -156,5 +156,5 @@ pte_library(
     FORMS ${forms}
     DEPENDS
         ptescore
-        Qt5::Widgets
+        Qt::Widgets
 )

source/dialogs/chordnamedialog.cpp

@@ -74,13 +74,7 @@ ChordNameDialog::ChordNameDialog(QWidget *parent,
     myTonicKeys->addButton(ui->tonicGButton, ChordName::G);
     myTonicKeys->addButton(ui->tonicAButton, ChordName::A);
     myTonicKeys->addButton(ui->tonicBButton, ChordName::B);
-    connect(myTonicKeys,
-#if (QT_VERSION >= QT_VERSION_CHECK(5,15,0))
-            &QButtonGroup::idClicked,
-#else
-            qOverload<int>(&QButtonGroup::buttonClicked),
-#endif
-            this, &ChordNameDialog::onTonicChanged);
+    connect(myTonicKeys, &QButtonGroup::idClicked, this, &ChordNameDialog::onTonicChanged);
 
     myBassKeys = new QButtonGroup(this);
     myBassKeys->addButton(ui->bassCButton, ChordName::C);
@@ -90,13 +84,7 @@ ChordNameDialog::ChordNameDialog(QWidget *parent,
     myBassKeys->addButton(ui->bassGButton, ChordName::G);
     myBassKeys->addButton(ui->bassAButton, ChordName::A);
     myBassKeys->addButton(ui->bassBButton, ChordName::B);
-    connect(myBassKeys,
-#if (QT_VERSION >= QT_VERSION_CHECK(5,15,0))
-            &QButtonGroup::idClicked,
-#else
-            qOverload<int>(&QButtonGroup::buttonClicked),
-#endif
-            this, &ChordNameDialog::updateState);
+    connect(myBassKeys, &QButtonGroup::idClicked, this, &ChordNameDialog::updateState);
 
     connect(ui->formulaListWidget,
             qOverload<int>(&QComboBox::currentIndexChanged), this,

source/dialogs/fileinformationdialog.cpp

@@ -175,11 +175,7 @@ FileInformationDialog::FileInformationDialog(
     ui->fileLocationValue->setText(filePath);
     ui->fileSizeValue->setText(
         tr("%1 bytes").arg(locale.toString(fileInfo.size())));
-#if (QT_VERSION >= QT_VERSION_CHECK(5,10,0))
     ui->fileCreatedValue->setText(locale.toString(fileInfo.birthTime()));
-#else
-    ui->fileCreatedValue->setText(locale.toString(fileInfo.created()));
-#endif
     ui->fileModifiedValue->setText(locale.toString(fileInfo.lastModified()));
     ui->fileAccessedValue->setText(locale.toString(fileInfo.lastRead()));
 }

source/dialogs/preferencesdialog.cpp

@@ -39,9 +39,6 @@ PreferencesDialog::PreferencesDialog(QWidget *parent,
 {
     ui->setupUi(this);
 
-    // Needed for findData() to work with QVariant's containing std::pair.
-    QMetaType::registerComparators<MidiApiAndPort>();
-
     connect(ui->buttonBox, &QDialogButtonBox::accepted, this, &QDialog::accept);
     connect(ui->buttonBox, &QDialogButtonBox::rejected, this, &QDialog::reject);
 

source/painters/CMakeLists.txt

@@ -55,5 +55,5 @@ pte_library(
     MOC_HEADERS ${moc_headers}
     DEPENDS
         ptescore
-        Qt5::Widgets
+        Qt::Widgets
 )