Merge pull request #2741

Workaround for WindowsVista style (qwindowsvistastyle plugin)

There is some strange bug on windows with the system styles (windows
and windowsvista).  When styleproxy is used and QDockWidget has a
custom stylesheet applied to the widget title, close-button and
float-button are rendered huge.

See #2485

src/Application.cpp

@@ -7,6 +7,10 @@
 #include <QDebug>
 #include <QAction>
 #include <QFileInfo>
+#include <QProxyStyle>
+#include <QStyleOption>
+#include <QDesktopWidget>
+#include <QScreen>
 
 #include "Application.h"
 #include "MainWindow.h"
@@ -15,6 +19,52 @@
 #include "version.h"
 #include "sqlitedb.h"
 
+class DB4SProxyStyle final : public QProxyStyle {
+public:
+    DB4SProxyStyle(int toolBarIconSize, qreal dpi, QStyle *style)
+        : QProxyStyle(style), m_toolBarIconSize(static_cast<int>(toolBarIconSize * dpi / 96))
+    {
+#ifdef Q_OS_WIN
+        m_smallIconSize = static_cast<int>(11 * dpi / 96);
+
+        QStyleOption so(QStyleOption::Version, QStyleOption::SO_MenuItem);
+        m_menuItemIconSize = style->pixelMetric(PM_SmallIconSize, &so);
+#endif
+    }
+
+    int pixelMetric(QStyle::PixelMetric metric,
+                    const QStyleOption *option = nullptr,
+                    const QWidget *widget = nullptr) const override
+    {
+        if (metric == PM_ToolBarIconSize) {
+            return m_toolBarIconSize;
+        }
+#ifdef Q_OS_WIN
+        else if (metric == PM_SmallIconSize) {
+            // set maximum icon size for SmallIcon
+
+            // Set default MenuIcon size
+            if (option && option->type == QStyleOption::SO_MenuItem) {
+                return m_menuItemIconSize;
+            }
+
+            // if we don't return size before QDockWidgets are created,
+            // any of the widgets with custom stylesheet are rendered with huge float,close buttons
+            // see void TableBrowserDock::setFocusStyle
+            return m_smallIconSize;
+        }
+#endif
+        return QProxyStyle::pixelMetric(metric, option, widget);
+    }
+
+private:
+    int m_toolBarIconSize;
+#ifdef Q_OS_WIN
+    int m_menuItemIconSize;
+    int m_smallIconSize;
+#endif
+};
+
 void printArgument(const QString& argument, const QString& description)
 {
     const int fieldWidth = 20;
@@ -32,11 +82,11 @@ Application::Application(int& argc, char** argv) :
     QApplication(argc, argv)
 {
     // Get 'DB4S_SETTINGS_FILE' environment variable
-    const char* env = getenv("DB4S_SETTINGS_FILE");
+    const auto env = qgetenv("DB4S_SETTINGS_FILE");
 
     // If 'DB4S_SETTINGS_FILE' environment variable exists
-    if(env)
-        Settings::setUserSettingsFile(QString::fromStdString(env));
+    if(!env.isEmpty())
+        Settings::setUserSettingsFile(env);
 
     for(int i=1;i<arguments().size();i++)
     {
@@ -44,10 +94,10 @@ Application::Application(int& argc, char** argv) :
         {
             if(++i < arguments().size())
             {
-                if(env)
+                if(!env.isEmpty())
                 {
                     qWarning() << qPrintable(tr("The user settings file location is replaced with the argument value instead of the environment variable value."));
-                    qWarning() << qPrintable(tr("Ignored environment variable(DB4S_SETTINGS_FILE) value : ") + QString::fromStdString(env));
+                    qWarning() << qPrintable(tr("Ignored environment variable(DB4S_SETTINGS_FILE) value : ") + env);
                 }
                 Settings::setUserSettingsFile(arguments().at(i));
             }
@@ -231,6 +281,10 @@ Application::Application(int& argc, char** argv) :
         return;
     }
 
+    // Set StyleProxy
+    QScreen *screen = primaryScreen();
+    setStyle(new DB4SProxyStyle(18, screen != nullptr ? screen->logicalDotsPerInch() : 96, style()));
+
     // Show main window
     m_mainWindow = new MainWindow();
     m_mainWindow->show();

src/TableBrowserDock.cpp

@@ -50,9 +50,17 @@ void TableBrowserDock::setFocusStyle(bool on)
 {
     // Highlight title bar when dock widget is active
     if(on)
-        setStyleSheet("QDockWidget::title {background:palette(highlight);}");
+        setStyleSheet(QStringLiteral(
+            "QDockWidget::title {"
+                "background:palette(AlternateBase);"
+                "text-align: center;"
+                "border-bottom: 2px solid palette(highlight);"
+            "}"));
     else
-        setStyleSheet(QString());
+        setStyleSheet(QStringLiteral(
+            "QDockWidget::title {"
+                "text-align: center;"
+            "}"));
 }
 
 void TableBrowserDock::showContextMenuTableBrowserTabBar(const QPoint& pos)

src/main.cpp

@@ -2,7 +2,6 @@
 #include "Application.h"
 #include "sqlite.h"
 #include <QMessageBox>
-#include <QProxyStyle>
 
 static QString message = QString();
 
@@ -28,36 +27,15 @@ void boxMessageOutput(QtMsgType, const QMessageLogContext &, const QString &msg)
     message += msg + "\n";
 }
 
-class DB4SProxyStyle final : public QProxyStyle {
-public:
-    DB4SProxyStyle(int toolBarIconSize)
-        : QProxyStyle(nullptr), toolBarIconSize_(toolBarIconSize) {}
-
-    int pixelMetric(QStyle::PixelMetric metric,
-                    const QStyleOption *option = nullptr,
-                    const QWidget *widget = nullptr) const override {
-
-        if (metric == QStyle::PM_ToolBarIconSize) {
-            return toolBarIconSize_;
-        }
-
-        return QProxyStyle::pixelMetric(metric, option, widget);
-    }
-
-private:
-    int toolBarIconSize_;
-};
-
 int main( int argc, char ** argv )
 {
-
 #if QT_VERSION >= QT_VERSION_CHECK(5, 6, 0)
-    QGuiApplication::setAttribute(Qt::AA_EnableHighDpiScaling, true);
+    QApplication::setAttribute(Qt::AA_EnableHighDpiScaling, true);
 #if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
-    QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::PassThrough);
+    QApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::PassThrough);
 #endif
 #endif
-    QGuiApplication::setAttribute(Qt::AA_UseHighDpiPixmaps, true);
+    QApplication::setAttribute(Qt::AA_UseHighDpiPixmaps, true);
 #ifdef Q_OS_WIN
     // In Windows, there is no output to terminal for a graphical application, so we install
     // the output to message box, until the main window is shown or the application exits.
@@ -67,9 +45,6 @@ int main( int argc, char ** argv )
     // Create application object. All the initialisation stuff happens in there
     Application a(argc, argv);
 
-    // Set default QToolbar->iconSize via StyleProxy
-    a.setStyle(new DB4SProxyStyle(16));
-
     // If there has been invocations to the message handler, show it to user in a message box.
     if(!message.isEmpty()) {
         QMessageBox messageBox;