Introduce a QVariant themeHint() to QPlatformTheme.

Start on removing platform-specific code from QtWidgets.

Change-Id: Ic2163a0ce6f2db2151cdf7ca93766b2d861eeb55
Reviewed-by: Samuel Rødal <samuel.rodal@nokia.com>

2 files changed, 34 insertions, 0 deletions

diff --git a/src/plugins/platforms/windows/qwindowstheme.cpp b/src/plugins/platforms/windows/qwindowstheme.cpp
index 4e1b004631..31adcfa167 100644
--- a/src/plugins/platforms/windows/qwindowstheme.cpp
+++ b/src/plugins/platforms/windows/qwindowstheme.cpp
@@ -41,13 +41,46 @@
 
 #include "qwindowstheme.h"
 #include "qwindowsdialoghelpers.h"
+#include "qwindowscontext.h"
+#include "qt_windows.h"
+
+#include <QtCore/QVariant>
 
 QT_BEGIN_NAMESPACE
 
+static inline bool booleanSystemParametersInfo(UINT what, bool defaultValue)
+{
+    BOOL result;
+    if (SystemParametersInfo(what, 0, &result, 0))
+        return result ? true : false;
+    return defaultValue;
+}
+
+static inline bool dWordSystemParametersInfo(UINT what, DWORD defaultValue)
+{
+    DWORD result;
+    if (SystemParametersInfo(what, 0, &result, 0))
+        return result;
+    return defaultValue;
+}
+
 QWindowsTheme::QWindowsTheme()
 {
 }
 
+QVariant QWindowsTheme::themeHint(ThemeHint hint) const
+{
+    switch (hint) {
+    case TextCursorWidth:
+        return QVariant(int(dWordSystemParametersInfo(SPI_GETCARETWIDTH, 1u)));
+    case DropShadow:
+        return QVariant(booleanSystemParametersInfo(SPI_GETDROPSHADOW, false));
+    case MaximumScrollBarDragDistance:
+        return QVariant(qRound(qreal(QWindowsContext::instance()->defaultDPI()) * 1.375));
+    }
+    return QVariant();
+}
+
 bool QWindowsTheme::usePlatformNativeDialog(const QDialog *dialog) const
 {
     return QWindowsDialogs::useHelper(dialog);
diff --git a/src/plugins/platforms/windows/qwindowstheme.h b/src/plugins/platforms/windows/qwindowstheme.h
index 67a0813835..9bb937d607 100644
--- a/src/plugins/platforms/windows/qwindowstheme.h
+++ b/src/plugins/platforms/windows/qwindowstheme.h
@@ -53,6 +53,7 @@ public:
 
     virtual bool usePlatformNativeDialog(const QDialog *dialog = 0) const;
     virtual QPlatformDialogHelper *createPlatformDialogHelper(QDialog *dialog = 0) const;
+    virtual QVariant themeHint(ThemeHint) const;
 };
 
 QT_END_NAMESPACE