Make code compatible with QT 5.9 (#1553)

* Make code compatible with QT 5.9, Ubuntu 18.04.

* Fix high dpi scaling in ColorThemeListView.

src/CMakeLists.txt

@@ -1,7 +1,9 @@
 
 cmake_minimum_required(VERSION 3.1)
 
-cmake_policy(SET CMP0074 NEW)
+if(${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.12.0")
+    cmake_policy(SET CMP0074 NEW)
+endif()
 
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 include(DisallowInSource)

src/Main.cpp

@@ -61,8 +61,8 @@ int main(int argc, char *argv[])
                 continue;
             }
             QJsonObject updatedTheme;
-            auto sch = ThemeWorker().getTheme(theme);
+            auto sch = ThemeWorker().getTheme(theme).object();
-            for (auto key : sch.object().keys()) {
+            for (auto key : sch.keys()) {
                 if (options.contains(key)) {
                     updatedTheme.insert(key, sch[key]);
                 }

src/dialogs/preferences/ColorThemeEditDialog.cpp

@@ -22,7 +22,10 @@ ColorThemeEditDialog::ColorThemeEditDialog(QWidget *parent) :
     previewDisasmWidget = new DisassemblyWidget(nullptr);
     previewDisasmWidget->setObjectName("Preview Disasm");
     previewDisasmWidget->setPreviewMode(true);
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 12, 0))
+    // default size limit is acceptable
     previewDisasmWidget->setMinimumSize(qApp->screenAt(previewDisasmWidget->pos())->size() * 0.5);
+#endif
     previewDisasmWidget->setWindowTitle(tr("Disassembly Preview"));
     previewDisasmWidget->setFeatures(QDockWidget::NoDockWidgetFeatures);
     ui->colorPickerAndPreviewLayout->addWidget(previewDisasmWidget);

src/widgets/ColorPicker.cpp

@@ -194,8 +194,7 @@ ColorPicker::ColorPicker(QWidget* parent) :
 ColorPicker::~ColorPicker()
 {
     if (pickingFromScreen) {
-        setColor(QApplication::screenAt(QCursor::pos())->grabWindow(QApplication::desktop()->winId())
+        setColor(getColorAtMouse());
-                .toImage().pixelColor(QCursor::pos()));
         stopPickingFromScreen();
     }
 }
@@ -282,11 +281,7 @@ void ColorPicker::startPickingFromScreen()
 void ColorPicker::mouseReleaseEvent(QMouseEvent* event)
 {
     if (pickingFromScreen) {
-        const QDesktopWidget *desktop = QApplication::desktop();
+        setColor(getColorAtMouse());
-        const QPixmap pixmap = QGuiApplication::screens().at(desktop->screenNumber())
-                               ->grabWindow(desktop->winId(),
-                                            QCursor::pos().x(), QCursor::pos().y(), 1, 1);
-        setColor(pixmap.toImage().pixel(0, 0));
         pickingFromScreen = false;
         setMouseTracking(false);
         releaseMouse();
@@ -297,15 +292,20 @@ void ColorPicker::mouseReleaseEvent(QMouseEvent* event)
 void ColorPicker::mouseMoveEvent(QMouseEvent* event)
 {
     if (pickingFromScreen) {
-        const QDesktopWidget *desktop = QApplication::desktop();
+        updateColor(getColorAtMouse());
-        const QPixmap pixmap = QGuiApplication::screens().at(desktop->screenNumber())
-                               ->grabWindow(desktop->winId(),
-                                            QCursor::pos().x(), QCursor::pos().y(), 1, 1);
-        updateColor(pixmap.toImage().pixel(0, 0));
     }
     QWidget::mouseMoveEvent(event);
 }
 
+QColor ColorPicker::getColorAtMouse()
+{
+    const QDesktopWidget *desktop = QApplication::desktop();
+    const QPixmap pixmap = QGuiApplication::screens().at(desktop->screenNumber())
+                           ->grabWindow(desktop->winId(),
+                                        QCursor::pos().x(), QCursor::pos().y(), 1, 1);
+    return pixmap.toImage().pixelColor(0, 0);
+}
+
 bool ColorPicker::isPickingFromScreen() const
 {
     return pickingFromScreen;

src/widgets/ColorPicker.h

@@ -79,6 +79,8 @@ private:
     Ui::ColorPicker *ui;
     bool pickingFromScreen;
 
+    QColor getColorAtMouse();
+
     /**
      * @brief bufferColor is used to buffer current color while picking from screen.
      */

src/widgets/ColorThemeListView.cpp

@@ -37,7 +37,7 @@ void ColorOptionDelegate::paint(QPainter *painter,
                                 const QStyleOptionViewItem &option,
                                 const QModelIndex &index) const
 {
-    int margin = this->margin * qApp->screenAt(option.rect.topLeft())->devicePixelRatio();
+    int margin = this->margin * painter->device()->devicePixelRatioF();
     painter->save();
     painter->setFont(option.font);
     painter->setRenderHint(QPainter::Antialiasing);
@@ -88,10 +88,16 @@ void ColorOptionDelegate::paint(QPainter *painter,
                 resetButtonRect.setSize(resetButtonRect.size() * 1.0);
             }
         } else {
-            QColor c = qApp->palette().placeholderText().color();
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 12, 0))
+            QColor placeholderColor = qApp->palette().placeholderText().color();
+#else
+            QColor placeholderColor = qApp->palette().text().color();
+            placeholderColor.setAlphaF(0.5);
+#endif
+            QColor c = placeholderColor;
             c.setAlphaF(0.2);
             br = c;
-            pen = QPen(qApp->palette().placeholderText().color().darker(), margin / 2);
+            pen = QPen(placeholderColor.darker(), margin / 2);
         }
 
         painter->fillRect(option.rect, br);
@@ -143,9 +149,9 @@ void ColorOptionDelegate::paint(QPainter *painter,
 
 QSize ColorOptionDelegate::sizeHint(const QStyleOptionViewItem& option, const QModelIndex& index) const
 {
-    int margin = this->margin * qApp->screenAt(option.rect.topLeft())->devicePixelRatio();
+    qreal margin = this->margin * option.widget->devicePixelRatioF();
-    int fontHeight = option.fontMetrics.height();
+    qreal fontHeight = option.fontMetrics.height();
-    int h = QPen().width();
+    qreal h = QPen().width();
     h += fontHeight; // option name
     h += margin / 2; // margin between option rect and option name
     h += margin / 4; // margin betveen option rect and color rect
@@ -154,7 +160,7 @@ QSize ColorOptionDelegate::sizeHint(const QStyleOptionViewItem& option, const QM
     h += margin; // last margin
 
     Q_UNUSED(index)
-    return QSize(-1, h);
+    return QSize(-1, qRound(h));
 }
 
 QRect ColorOptionDelegate::getResetButtonRect() const
@@ -187,6 +193,7 @@ ColorThemeListView::ColorThemeListView(QWidget *parent) :
     setModel(new ColorSettingsModel(static_cast<QObject *>(this)));
     static_cast<ColorSettingsModel *>(this->model())->updateTheme();
     setItemDelegate(new ColorOptionDelegate(this));
+    setResizeMode(ResizeMode::Adjust);
 
     QJsonArray rgb = qobject_cast<ColorSettingsModel*>(model())->getTheme()
                      .object().find("gui.background").value().toArray();
@@ -235,7 +242,8 @@ void ColorThemeListView::mouseReleaseEvent(QMouseEvent* e)
         auto model = qobject_cast<ColorSettingsModel*>(this->model());
         ColorOption co = currentIndex().data(Qt::UserRole).value<ColorOption>();
         co.changed = false;
-        QJsonArray rgb = ThemeWorker().getTheme(Config()->getColorTheme())[co.optionName].toArray();
+        QJsonArray rgb = ThemeWorker().getTheme(
+                             Config()->getColorTheme()).object()[co.optionName].toArray();
         co.color = QColor(rgb[0].toInt(), rgb[1].toInt(), rgb[2].toInt());
         model->setData(currentIndex(), QVariant::fromValue(co));
         QCursor c;