Do not crash QML apps on startup

This started crashing because of 8f6436f125faae91eb472ddddbbae06dba5da671

Task-number: QTBUG-42227
Change-Id: I9e4862f6008c6ad6ec54469f2b39dd6be583e422
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>

2 files changed, 16 insertions, 9 deletions

diff --git a/src/quick/items/qquickaccessibleattached.cpp b/src/quick/items/qquickaccessibleattached.cpp
index 38b26a53d0..abb763c2eb 100644
--- a/src/quick/items/qquickaccessibleattached.cpp
+++ b/src/quick/items/qquickaccessibleattached.cpp
@@ -292,10 +292,10 @@ QT_BEGIN_NAMESPACE
     The corresponding handler is \c onDecreaseAction.
 */
 
-const QMetaMethod QQuickAccessibleAttached::sigPress = QMetaMethod::fromSignal(&QQuickAccessibleAttached::pressAction);
-const QMetaMethod QQuickAccessibleAttached::sigToggle = QMetaMethod::fromSignal(&QQuickAccessibleAttached::toggleAction);
-const QMetaMethod QQuickAccessibleAttached::sigIncrease = QMetaMethod::fromSignal(&QQuickAccessibleAttached::increaseAction);
-const QMetaMethod QQuickAccessibleAttached::sigDecrease = QMetaMethod::fromSignal(&QQuickAccessibleAttached::decreaseAction);
+QMetaMethod QQuickAccessibleAttached::sigPress;
+QMetaMethod QQuickAccessibleAttached::sigToggle;
+QMetaMethod QQuickAccessibleAttached::sigIncrease;
+QMetaMethod QQuickAccessibleAttached::sigDecrease;
 
 QQuickAccessibleAttached::QQuickAccessibleAttached(QObject *parent)
     : QObject(parent), m_role(QAccessible::NoRole)
@@ -317,6 +317,13 @@ QQuickAccessibleAttached::QQuickAccessibleAttached(QObject *parent)
     if (!parent->property("cursorPosition").isNull()) {
         connect(parent, SIGNAL(cursorPositionChanged()), this, SLOT(cursorPositionChanged()));
     }
+
+    if (!sigPress.isValid()) {
+        sigPress = QMetaMethod::fromSignal(&QQuickAccessibleAttached::pressAction);
+        sigToggle = QMetaMethod::fromSignal(&QQuickAccessibleAttached::toggleAction);
+        sigIncrease = QMetaMethod::fromSignal(&QQuickAccessibleAttached::increaseAction);
+        sigDecrease = QMetaMethod::fromSignal(&QQuickAccessibleAttached::decreaseAction);
+    }
 }
 
 QQuickAccessibleAttached::~QQuickAccessibleAttached()
@@ -343,7 +350,7 @@ void QQuickAccessibleAttached::setIgnored(bool ignored)
 
 bool QQuickAccessibleAttached::doAction(const QString &actionName)
 {
-    const QMetaMethod *sig = 0;
+    QMetaMethod *sig = 0;
     if (actionName == QAccessibleActionInterface::pressAction())
         sig = &sigPress;
     else if (actionName == QAccessibleActionInterface::toggleAction())
diff --git a/src/quick/items/qquickaccessibleattached_p.h b/src/quick/items/qquickaccessibleattached_p.h
index 53b1d2954d..ad6165f936 100644
--- a/src/quick/items/qquickaccessibleattached_p.h
+++ b/src/quick/items/qquickaccessibleattached_p.h
@@ -221,10 +221,10 @@ private:
     QString m_name;
     QString m_description;
 
-    static const QMetaMethod sigPress;
-    static const QMetaMethod sigToggle;
-    static const QMetaMethod sigIncrease;
-    static const QMetaMethod sigDecrease;
+    static QMetaMethod sigPress;
+    static QMetaMethod sigToggle;
+    static QMetaMethod sigIncrease;
+    static QMetaMethod sigDecrease;
 
 public:
     using QObject::property;