Allow picking up tool button style from the system

KDE and GNOME has the concept of a default tool button style that
can be set system-wide. Qt currently allways default to IconOnly.
I have added an optional Qt::ToolButtonSystemDefault value so you
can opt-in to respect the system setting. We did not change the
default because a lot of apps will look odd when for instance
text is beside icons and the descriptive text is too long.

Task-number: 237864
Reviewed-by: ogoffart

7 files changed, 88 insertions, 4 deletions

diff --git a/src/gui/styles/gtksymbols.cpp b/src/gui/styles/gtksymbols.cpp
index f553d27..2b32450 100644
--- a/src/gui/styles/gtksymbols.cpp
+++ b/src/gui/styles/gtksymbols.cpp
@@ -68,6 +68,7 @@
 #include <QtGui/QStatusBar>
 #include <QtGui/QMenuBar>
 #include <QtGui/QToolBar>
+#include <QtGui/QToolButton>
 #include <QtGui/QX11Info>
 
 #include <X11/Xlib.h>
@@ -633,6 +634,20 @@ GtkStyle* QGtk::gtkStyle(const QString &path)
     return 0;
 }
 
+static void update_toolbar_style(GtkWidget *gtkToolBar, GParamSpec *pspec, gpointer user_data)
+{
+    GtkToolbarStyle toolbar_style = GTK_TOOLBAR_ICONS;
+    g_object_get(gtkToolBar, "toolbar-style", &toolbar_style, NULL);
+    QWidgetList widgets = QApplication::allWidgets();
+    for (int i = 0; i < widgets.size(); ++i) {
+        QWidget *widget = widgets.at(i);
+        if (qobject_cast<QToolButton*>(widget)) {
+            QEvent event(QEvent::StyleChange);
+            QApplication::sendEvent(widget, &event);
+        }
+    }
+}
+
 void QGtk::initGtkWidgets()
 {
     // From gtkmain.c
@@ -679,6 +694,7 @@ void QGtk::initGtkWidgets()
             add_widget(QGtk::gtk_spin_button_new((GtkAdjustment*)
                                              (QGtk::gtk_adjustment_new(1, 0, 1, 0, 0, 0)), 0.1, 3));
             GtkWidget *toolbar = QGtk::gtk_toolbar_new();
+            g_signal_connect (toolbar, "notify::toolbar-style", G_CALLBACK (update_toolbar_style), toolbar);
             QGtk::gtk_toolbar_insert((GtkToolbar*)toolbar, QGtk::gtk_separator_tool_item_new(), -1);
             add_widget(toolbar);
             init_gtk_treeview();
diff --git a/src/gui/styles/qcommonstyle.cpp b/src/gui/styles/qcommonstyle.cpp
index 7b8b75e..29176c3 100644
--- a/src/gui/styles/qcommonstyle.cpp
+++ b/src/gui/styles/qcommonstyle.cpp
@@ -840,6 +840,11 @@ static void drawArrow(const QStyle *style, const QStyleOptionToolButton *toolbut
 
 
 #ifdef Q_WS_X11 // These functions are used to parse the X11 freedesktop icon spec
+static int kdeVersion()
+{
+    static int kdeVersion = qgetenv("KDE_SESSION_VERSION").toInt();
+    return kdeVersion;
+}
 
 void QCommonStylePrivate::lookupIconTheme() const
 {
@@ -858,8 +863,7 @@ void QCommonStylePrivate::lookupIconTheme() const
 
     QFileInfo fileInfo(QLatin1String("/usr/share/icons/default.kde"));
     QDir dir(fileInfo.canonicalFilePath());
-    int kdeVersion = qgetenv("KDE_SESSION_VERSION").toInt();
-    QString kdeDefault = kdeVersion >= 4 ? QString::fromLatin1("oxygen") : QString::fromLatin1("crystalsvg");
+    QString kdeDefault = kdeVersion() >= 4 ? QString::fromLatin1("oxygen") : QString::fromLatin1("crystalsvg");
     QString defaultTheme = fileInfo.exists() ? dir.dirName() : kdeDefault;
     QSettings settings(QApplicationPrivate::kdeHome() +
                        QLatin1String("/share/config/kdeglobals"), QSettings::IniFormat);
@@ -997,6 +1001,29 @@ QIcon QCommonStylePrivate::createIcon(const QString &name) const
     icon.addPixmap(findIcon(32, name));
     return icon;
 }
+/*!internal
+
+Checks if you are running KDE and looks up the toolbar
+from the KDE configuration file
+
+*/
+int QCommonStylePrivate::lookupToolButtonStyle() const
+{
+    int result = Qt::ToolButtonIconOnly;
+    if (kdeVersion() >= 4) {
+        QSettings settings(QApplicationPrivate::kdeHome() +
+                           QLatin1String("/share/config/kdeglobals"), QSettings::IniFormat);
+        settings.beginGroup(QLatin1String("Toolbar style"));
+        QString toolbarStyle = settings.value(QLatin1String("ToolButtonStyle"), QLatin1String("TextBesideIcon")).toString();
+        if (toolbarStyle == QLatin1String("TextBesideIcon"))
+            result = Qt::ToolButtonTextBesideIcon;
+        else if (toolbarStyle == QLatin1String("TextOnly"))
+            result = Qt::ToolButtonTextOnly;
+        else if (toolbarStyle == QLatin1String("TextUnderIcon"))
+            result = Qt::ToolButtonTextUnderIcon;
+    }
+    return result;
+}
 
 #endif //Q_WS_X11
 
@@ -5290,6 +5317,16 @@ int QCommonStyle::styleHint(StyleHint sh, const QStyleOption *opt, const QWidget
     case SH_DockWidget_ButtonsHaveFrame:
         ret = true;
         break;
+    case SH_ToolButtonStyle:
+        ret = Qt::ToolButtonIconOnly;
+#ifdef Q_WS_X11
+        {
+            Q_D(const QCommonStyle);
+            static int buttonStyle = d->lookupToolButtonStyle();
+            return buttonStyle;
+        }
+#endif
+        break;
     default:
         ret = 0;
         break;
diff --git a/src/gui/styles/qcommonstyle_p.h b/src/gui/styles/qcommonstyle_p.h
index 27ebc05..f2af5b2 100644
--- a/src/gui/styles/qcommonstyle_p.h
+++ b/src/gui/styles/qcommonstyle_p.h
@@ -126,6 +126,7 @@ public:
 //icon detection on X11
 #ifdef Q_WS_X11
     void lookupIconTheme() const;
+    int lookupToolButtonStyle() const;
     QIcon createIcon(const QString &) const;
     QPixmap findIcon(int size, const QString &) const;
     QPixmap findIconHelper(int size, const QString &, const QString &, QStringList &visited) const;
diff --git a/src/gui/styles/qgtkstyle.cpp b/src/gui/styles/qgtkstyle.cpp
index 9d5a3bc..b6ef4c9 100644
--- a/src/gui/styles/qgtkstyle.cpp
+++ b/src/gui/styles/qgtkstyle.cpp
@@ -599,6 +599,26 @@ int QGtkStyle::styleHint(StyleHint hint, const QStyleOption *option, const QWidg
 
     break;
 
+    case SH_ToolButtonStyle:
+    {
+        if (QGtk::isKDE4Session())
+            return QCleanlooksStyle::styleHint(hint, option, widget, returnData);
+        GtkWidget *gtkToolbar = QGtk::gtkWidget(QLS("GtkToolbar"));
+        GtkToolbarStyle toolbar_style = GTK_TOOLBAR_ICONS;
+        g_object_get(gtkToolbar, "toolbar-style", &toolbar_style, NULL);
+        switch (toolbar_style) {
+        case GTK_TOOLBAR_TEXT:
+            return Qt::ToolButtonTextOnly;
+        case GTK_TOOLBAR_BOTH:
+            return Qt::ToolButtonTextUnderIcon;
+        case GTK_TOOLBAR_BOTH_HORIZ:
+            return Qt::ToolButtonTextBesideIcon;
+        case GTK_TOOLBAR_ICONS:
+        default:
+            return Qt::ToolButtonIconOnly;
+        }
+    }
+    break;
     case SH_SpinControls_DisableOnBounds:
         return int(true);
 
diff --git a/src/gui/styles/qstyle.cpp b/src/gui/styles/qstyle.cpp
index 797886c..bccd766 100644
--- a/src/gui/styles/qstyle.cpp
+++ b/src/gui/styles/qstyle.cpp
@@ -1865,6 +1865,8 @@ void QStyle::drawItemPixmap(QPainter *painter, const QRect &rect, int alignment,
 
     \value SH_DockWidget_ButtonsHaveFrame Determines if dockwidget buttons should have frames. Default is true.
 
+    \value SH_ToolButtonStyle Determines the default system style for tool buttons that uses Qt::ToolButtonSystemDefault.
+
     \omitvalue SH_UnderlineAccelerator
 
     \sa styleHint()
diff --git a/src/gui/styles/qstyle.h b/src/gui/styles/qstyle.h
index d79c39c..f22bf55 100644
--- a/src/gui/styles/qstyle.h
+++ b/src/gui/styles/qstyle.h
@@ -730,7 +730,7 @@ public:
         SH_ItemView_DrawDelegateFrame,
         SH_TabBar_CloseButtonPosition,
         SH_DockWidget_ButtonsHaveFrame,
-
+        SH_ToolButtonStyle,
         // Add new style hint values here
 
 #ifdef QT3_SUPPORT
diff --git a/src/gui/widgets/qtoolbutton.cpp b/src/gui/widgets/qtoolbutton.cpp
index 6dcbfec..5d0a98a 100644
--- a/src/gui/widgets/qtoolbutton.cpp
+++ b/src/gui/widgets/qtoolbutton.cpp
@@ -378,7 +378,11 @@ void QToolButton::initStyleOption(QStyleOptionToolButton *option) const
     if (d->hasMenu())
         option->features |= QStyleOptionToolButton::HasMenu;
 #endif
-    option->toolButtonStyle = d->toolButtonStyle;
+    if (d->toolButtonStyle == Qt::ToolButtonSystemDefault) {
+        option->toolButtonStyle = Qt::ToolButtonStyle(style()->styleHint(QStyle::SH_ToolButtonStyle, option, this));
+    } else
+        option->toolButtonStyle = d->toolButtonStyle;
+
     if (d->icon.isNull() && d->arrowType == Qt::NoArrow && !forceNoText) {
         if (!d->text.isEmpty())
             option->toolButtonStyle = Qt::ToolButtonTextOnly;
@@ -476,6 +480,10 @@ QSize QToolButton::minimumSizeHint() const
 
     The default is Qt::ToolButtonIconOnly.
 
+    If you want your toolbars to depend on system settings,
+    as is possible in GNOME and KDE desktop environments you should
+    use the ToolButtonSystemDefault.
+
     QToolButton automatically connects this slot to the relevant
     signal in the QMainWindow in which is resides.
 */