Port Liquid to Qt6

.github/workflows/ci.yml

@@ -16,41 +16,60 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     strategy:
+      fail-fast: false
       matrix:
         include:
-          - os: ubuntu-18.04
-          - os: ubuntu-20.04
-          - os: macos-10.15
-          - os: macos-11
-          - os: windows-2019
+          # Qt 5.15 from distro packages
+          - os: ubuntu-22.04
+            qt: 5
+          # Qt 6 from distro packages
+          - os: ubuntu-24.04
+            qt: 6
+          # Qt 6 from the Qt online repository
+          - os: macos-14
+            qt: 6
           - os: windows-2022
-
-    continue-on-error: true
+            qt: 6
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
+
     - uses: ilammy/msvc-dev-cmd@v1
+      if: runner.os == 'Windows'
+
+    - name: Resolve dependencies (Ubuntu, Qt 5)
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y qtbase5-dev qtwebengine5-dev qt5-qmake
+        echo "QMAKE=qmake" >> "$GITHUB_ENV"
+      if: runner.os == 'Linux' && matrix.qt == 5
 
-    - name: Resolve dependencies (Ubuntu)
+    - name: Resolve dependencies (Ubuntu, Qt 6)
       run: |
-        sudo apt-get update && \
-        sudo apt-get install qt5-default qtwebengine5-dev
-      if: contains(matrix.os, 'ubuntu')
+        sudo apt-get update
+        sudo apt-get install -y qt6-base-dev qt6-webengine-dev qmake6 libgl-dev
+        echo "QMAKE=qmake6" >> "$GITHUB_ENV"
+      if: runner.os == 'Linux' && matrix.qt == 6
 
     - name: Resolve dependencies (macOS and Windows)
-      uses: jurplel/install-qt-action@v2
+      uses: jurplel/install-qt-action@v4
       with:
-          modules: 'qtwebengine'
-      if: contains(matrix.os, 'macos') || contains(matrix.os, 'windows')
+        version: '6.8.*'
+        modules: 'qtwebengine qtwebchannel qtpositioning'
+      if: runner.os != 'Linux'
+
+    - name: Resolve dependencies (macOS icon tools)
+      run: brew install imagemagick
+      if: runner.os == 'macOS'
 
     - name: Build (Ubuntu and macOS)
       run: |
-        qmake
+        ${QMAKE:-qmake}
         make -j
-      if: contains(matrix.os, 'ubuntu') || contains(matrix.os, 'macos')
+      if: runner.os != 'Windows'
 
     - name: Build (Windows)
       run: |
         qmake
         nmake
-      if: contains(matrix.os, 'windows')
+      if: runner.os == 'Windows'

README.md

@@ -73,13 +73,27 @@ What gets stored (if allowed): cookies.
 
 ## Working with the codebase
 
+#### Dependencies
+
+Liquid is built with Qt 6 (Qt 5.15 is still supported) and Qt WebEngine.
+
+On Debian/Ubuntu:
+
+```console
+sudo apt install qt6-base-dev qt6-webengine-dev qmake6 build-essential
+```
+
+On macOS and Windows, install Qt 6 with the Qt WebEngine, Qt WebChannel, and Qt Positioning modules using the [Qt Online Installer](https://www.qt.io/download-qt-installer).
+
 #### Build
 
 ```console
-qmake
+qmake6
 make -j
 ```
 
+Use `qmake` instead of `qmake6` if it already points to Qt 6 (or to Qt 5.15) on your system.
+
 #### Install
 
 ```console

inc/liquidappwebpage.hpp

@@ -2,6 +2,7 @@
 
 #include <QAuthenticator>
 #include <QDialog>
+#include <QWebEngineCertificateError>
 #include <QWebEnginePage>
 #include <QWebEngineProfile>
 
@@ -27,7 +28,11 @@ class LiquidAppWebPage : public QWebEnginePage
     bool acceptNavigationRequest(const QUrl& reqUrl, const QWebEnginePage::NavigationType navReqType, const bool isMainFrame) override;
 
 private:
-    bool certificateError(const QWebEngineCertificateError& error);
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+    bool certificateError(const QWebEngineCertificateError& error) override;
+#else
+    void handleCertificateError(const QWebEngineCertificateError& error);
+#endif
     void javaScriptAlert(const QUrl& securityOrigin, const QString& msg) override;
     bool javaScriptConfirm(const QUrl& securityOrigin, const QString& msg) override;
     bool javaScriptPrompt(const QUrl& securityOrigin, const QString& msg, const QString& defaultValue, QString* result) override;

liquid.pro

@@ -4,8 +4,8 @@ VERSION_PATCH = 11
 
 VERSION      = $${VERSION_MAJOR}.$${VERSION_MINOR}.$${VERSION_PATCH}
 
-QT          += core gui webenginewidgets
-CONFIG      += c++11
+QT          += core gui network widgets webenginecore webenginewidgets
+CONFIG      += c++17
 TEMPLATE     = app
 
 DESTDIR      = build
@@ -85,7 +85,7 @@ unix:!mac {
 # macOS
 macx: {
     HEADERS += inc/SetWindowBackgroundColor.h
-    OBJECTIVE_SOURCES += src/SetWindowBackgroundColor.mm
+    SOURCES += src/SetWindowBackgroundColor.mm
 
     LIBS += -framework Cocoa
 
@@ -107,5 +107,7 @@ macx: {
         QMAKE_PRE_LINK += iconutil -c icns $${DESTDIR}/$${TARGET}.iconset
     }
 
+    # Qt 6 no longer creates Contents/Resources inside the app bundle on its own
+    QMAKE_POST_LINK += mkdir -p $${DESTDIR}/$${TARGET}.app/Contents/Resources &&
     QMAKE_POST_LINK += cp $${DESTDIR}/$${TARGET}.icns $${DESTDIR}/$${TARGET}.app/Contents/Resources/
 }

src/liquid.cpp

@@ -7,6 +7,7 @@
 #include <QDebug>
 #include <QProcess>
 #include <QSettings>
+#include <QSysInfo>
 #include <QTime>
 #include <QWebEngineProfile>
 

src/liquidappconfigwindow.cpp

@@ -379,7 +379,7 @@ LiquidAppConfigDialog::LiquidAppConfigDialog(QWidget* parent, QString liquidAppN
                 customBackgroundColorButtonLayout->addWidget(customBackgroundColorButton);
 
                 connect(customBackgroundColorButton, &QPushButton::clicked, [&]() {
-                    const QColorDialog::ColorDialogOptions options = QFlag(QColorDialog::ShowAlphaChannel);
+                    const QColorDialog::ColorDialogOptions options = QColorDialog::ShowAlphaChannel;
                     QColor color = QColorDialog::getColor(*backgroundColor, this, tr("Pick custom background color"), options);
 
                     if (color.isValid()) {
@@ -746,7 +746,7 @@ LiquidAppConfigDialog::LiquidAppConfigDialog(QWidget* parent, QString liquidAppN
                 connect(proxyPortInput, QOverload<int>::of(&QSpinBox::valueChanged), [&](){
                     proxyModeCustomRadioButton->setChecked(true);
                 });
-                connect(proxyUseAuthCheckBox, &QCheckBox::stateChanged, [&](){
+                connect(proxyUseAuthCheckBox, &QCheckBox::toggled, [&](){
                     proxyModeCustomRadioButton->setChecked(true);
                 });
                 connect(proxyUsernameInput, &QLineEdit::textChanged, [&](const QString value){

src/liquidappwebpage.cpp

@@ -24,6 +24,11 @@ LiquidAppWebPage::LiquidAppWebPage(QWebEngineProfile* profile, LiquidAppWindow*
     });
 
     connect(this, &QWebEnginePage::authenticationRequired, this, &LiquidAppWebPage::authenticationRequired);
+
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+    // Qt 6 turned QWebEnginePage::certificateError() from a virtual method into a signal
+    connect(this, &QWebEnginePage::certificateError, this, &LiquidAppWebPage::handleCertificateError);
+#endif
 }
 
 void LiquidAppWebPage::addAllowedDomain(const QString domain) {
@@ -107,14 +112,26 @@ void LiquidAppWebPage::authenticationRequired(const QUrl& requestUrl, QAuthentic
     dialogWidget = Q_NULLPTR;
 }
 
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 bool LiquidAppWebPage::certificateError(const QWebEngineCertificateError& error)
 {
     Q_UNUSED(error);
 
     emit liquidAppWindow->certificateError();
 
+    // Ignore the error and proceed with loading the page
     return true;
 }
+#else
+void LiquidAppWebPage::handleCertificateError(const QWebEngineCertificateError& error)
+{
+    // Ignore the error and proceed with loading the page
+    QWebEngineCertificateError err = error;
+    err.acceptCertificate();
+
+    emit liquidAppWindow->certificateError();
+}
+#endif
 
 void LiquidAppWebPage::closeJsDialog()
 {