Fix background of QAbstractScrollArea when styled only with pseudo-class

This may happen if you only have something like
QAbstractScrollArea:focus { background: foo; }
and you do not have a background set for the general case
and the viewport has a different background role (such as QTextEdit,
QAbstractItemView, ....)

This is a regression from 4.4 since in 4.4 the :focus has no effect if
you didn't have a background for the general case.

Reviewed-by: bnilsen
Task-number: 188195

2 files changed, 36 insertions, 1 deletions

diff --git a/src/gui/styles/qstylesheetstyle.cpp b/src/gui/styles/qstylesheetstyle.cpp
index f22cd56..a39eeb7 100644
--- a/src/gui/styles/qstylesheetstyle.cpp
+++ b/src/gui/styles/qstylesheetstyle.cpp
@@ -2916,6 +2916,10 @@ void QStyleSheetStyle::polish(QWidget *w)
         if (ew->autoFillBackground()) {
             ew->setAutoFillBackground(false);
             autoFillDisabledWidgets->insert(w);
+            if (ew != w) { //eg. viewport of a scrollarea
+                //(in order to draw the background anyway in case we don't.)
+                ew->setAttribute(Qt::WA_StyledBackground, true);
+            }
         }
         if (!rule.hasBackground() || rule.background()->isTransparent() || rule.hasBox()
             || (!rule.hasNativeBorder() && !rule.border()->isOpaque()))
@@ -4345,8 +4349,16 @@ void QStyleSheetStyle::drawPrimitive(PrimitiveElement pe, const QStyleOption *op
         return;
 
     case PE_Widget:
-        if (!rule.hasBackground())
+        if (!rule.hasBackground()) {
+            QWidget *container = containerWidget(w);
+            if (autoFillDisabledWidgets->contains(container)
+                && (container == w || !renderRule(container, opt).hasBackground())) {
+                //we do not have a background, but we disabled the autofillbackground anyway. so fill the background now.
+                // (this may happen if we have rules like :focus)
+                p->fillRect(opt->rect, opt->palette.brush(w->backgroundRole()));
+            }
             break;
+        }
 
 #ifndef QT_NO_SCROLLAREA
         if (const QAbstractScrollArea *sa = qobject_cast<const QAbstractScrollArea *>(w)) {
diff --git a/tests/auto/qstylesheetstyle/tst_qstylesheetstyle.cpp b/tests/auto/qstylesheetstyle/tst_qstylesheetstyle.cpp
index 7954d00..aa63753 100644
--- a/tests/auto/qstylesheetstyle/tst_qstylesheetstyle.cpp
+++ b/tests/auto/qstylesheetstyle/tst_qstylesheetstyle.cpp
@@ -94,6 +94,7 @@ private slots:
     void embeddedFonts();
     void opaquePaintEvent_data();
     void opaquePaintEvent();
+    void task188195_baseBackground();
 
     //at the end because it mess with the style.
     void widgetStyle();
@@ -1354,6 +1355,28 @@ void tst_QStyleSheetStyle::opaquePaintEvent()
     QCOMPARE(cl.autoFillBackground(), !styled );
 }
 
+void tst_QStyleSheetStyle::task188195_baseBackground()
+{
+    QTreeView tree;
+    tree.setStyleSheet( "QTreeView:disabled { background-color:#ab1251; }" );
+    tree.show();
+    QTest::qWait(20);
+    QImage image(tree.width(), tree.height(), QImage::Format_ARGB32);
+    
+    tree.render(&image);
+    QVERIFY(testForColors(image, tree.palette().base().color()));
+    QVERIFY(!testForColors(image, QColor(0xab, 0x12, 0x51)));
+
+    tree.setEnabled(false);
+    tree.render(&image);
+    QVERIFY(testForColors(image, QColor(0xab, 0x12, 0x51)));
+
+    tree.setEnabled(true);
+    tree.render(&image);
+    QVERIFY(testForColors(image, tree.palette().base().color()));
+    QVERIFY(!testForColors(image, QColor(0xab, 0x12, 0x51)));
+}
+
 
 
 QTEST_MAIN(tst_QStyleSheetStyle)