Improve highligted colorization on mac with Fusion style

This mimics the platform behavior of using blue color when
the system palette is in use.

Change-Id: I9ad6a552614a3466a930ad5b28fc70d9343d2022
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>

2 files changed, 27 insertions, 3 deletions

diff --git a/src/widgets/styles/qfusionstyle.cpp b/src/widgets/styles/qfusionstyle.cpp
index 8e52a4b425..4121292cc7 100644
--- a/src/widgets/styles/qfusionstyle.cpp
+++ b/src/widgets/styles/qfusionstyle.cpp
@@ -1417,7 +1417,7 @@ void QFusionStyle::drawControl(ControlElement element, const QStyleOption *optio
             QRect leftRect;
             QRect rect = bar->rect;
             QColor textColor = option->palette.text().color();
-            QColor alternateTextColor = option->palette.highlightedText().color();
+            QColor alternateTextColor = d->highlightedText(option->palette);
 
             painter->save();
             bool vertical = false, inverted = false;
diff --git a/src/widgets/styles/qfusionstyle_p.h b/src/widgets/styles/qfusionstyle_p.h
index 1c8089e736..affb85bbb1 100644
--- a/src/widgets/styles/qfusionstyle_p.h
+++ b/src/widgets/styles/qfusionstyle_p.h
@@ -55,6 +55,8 @@
 
 #include "qcommonstyle.h"
 #include "qcommonstyle_p.h"
+#include <qpa/qplatformtheme.h>
+#include "private/qguiapplication_p.h"
 
 #ifndef QT_NO_STYLE_FUSION
 
@@ -83,10 +85,32 @@ public:
         return QColor(255, 255, 255, 30);
     }
 
+    // On mac we want a standard blue color used when the system palette is used
+    bool isMacSystemPalette(const QPalette &pal) const {
+        Q_UNUSED(pal);
+#ifdef Q_OS_MAC
+        const QPalette *themePalette = QGuiApplicationPrivate::platformTheme()->palette();
+        if (themePalette->color(QPalette::Normal, QPalette::Highlight) ==
+                pal.color(QPalette::Normal, QPalette::Highlight) &&
+            themePalette->color(QPalette::Normal, QPalette::HighlightedText) ==
+                pal.color(QPalette::Normal, QPalette::HighlightedText))
+            return true;
+#endif
+        return false;
+    }
+
     QColor highlight(const QPalette &pal) const {
+        if (isMacSystemPalette(pal))
+            return QColor(60, 140, 230);
         return pal.color(QPalette::Active, QPalette::Highlight);
     }
 
+    QColor highlightedText(const QPalette &pal) const {
+        if (isMacSystemPalette(pal))
+            return Qt::white;
+        return pal.color(QPalette::Active, QPalette::HighlightedText);
+    }
+
     QColor outline(const QPalette &pal) const {
         if (!pal.window().texture().isNull())
             return QColor(0, 0, 0, 160);
@@ -94,7 +118,7 @@ public:
     }
 
     QColor highlightedOutline(const QPalette &pal) const {
-        QColor highlightedOutline = pal.highlight().color().darker(125);
+        QColor highlightedOutline = highlight(pal).darker(125);
         if (highlightedOutline.value() > 160)
             highlightedOutline.setHsl(highlightedOutline.hue(), highlightedOutline.saturation(), 160);
         return highlightedOutline;
@@ -109,7 +133,7 @@ public:
     QColor buttonColor(const QPalette &pal) const {
         QColor buttonColor = pal.button().color();
         int val = qGray(buttonColor.rgb());
-        buttonColor = buttonColor.lighter(100 + qMax(0, (180- val)/6));
+        buttonColor = buttonColor.lighter(100 + qMax(1, (180 - val)/6));
         buttonColor.setHsv(buttonColor.hue(), buttonColor.saturation() * 0.75, buttonColor.value());
         return buttonColor;
     }