Native style: Fix bug in layoutMargins()

It should return margin of 0 if

  style()->subElementRect(XXXLayoutItem)

returned an invalid rect.

This means that we cannot rely on m_styleItemGeometry.layoutRect
blindly.

Change-Id: If6b5a40481c8199a63f3446abc9e7dd1c670d181
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

2 files changed, 7 insertions, 3 deletions

diff --git a/src/imports/nativestyle/items/qquickstyleitem.cpp b/src/imports/nativestyle/items/qquickstyleitem.cpp
index 5899e3ce..e59439ab 100644
--- a/src/imports/nativestyle/items/qquickstyleitem.cpp
+++ b/src/imports/nativestyle/items/qquickstyleitem.cpp
@@ -433,8 +433,12 @@ QQuickStyleMargins QQuickStyleItem::layoutMargins() const
     // than the control(frame) itself, to e.g make room for shadow effects
     // or focus rects/glow. And this will differ from control to control. The
     // layoutRect will then inform where the frame of the control is.
-    const QRect outerRect(QPoint(0, 0), m_styleItemGeometry.implicitSize);
-    return QQuickStyleMargins(outerRect, m_styleItemGeometry.layoutRect);
+    QQuickStyleMargins margins;
+    if (m_styleItemGeometry.layoutRect.isValid()) {
+        const QRect outerRect(QPoint(0, 0), m_styleItemGeometry.implicitSize);
+        margins = QQuickStyleMargins(outerRect, m_styleItemGeometry.layoutRect);
+    }
+    return margins;
 }
 
 QSize QQuickStyleItem::minimumSize() const
diff --git a/src/imports/nativestyle/items/qquickstyleitem.h b/src/imports/nativestyle/items/qquickstyleitem.h
index 2c8c9920..4e4180c1 100644
--- a/src/imports/nativestyle/items/qquickstyleitem.h
+++ b/src/imports/nativestyle/items/qquickstyleitem.h
@@ -144,7 +144,7 @@ struct StyleItemGeometry
     QSize minimumSize;
     QSize implicitSize;
     QRect contentRect;
-    QRect layoutRect;
+    QRect layoutRect;   //If invalid, there are no layout margins!
     QMargins ninePatchMargins;
     qreal focusFrameRadius;
 };