Add support for QEvent::LanguageChange

Respond to the language change event by refreshing all binding
expressions. For constant string translation bindings we must now create
special QQmlBinding instances instead of a one-time property write
meta-call upon instantiation. Those however are more lightweight than an
entire JavaScript expression.

In addition this provides a slot to explicitly trigger a re-evaluation
of bindings, to make it a little easier to discover for the developer.

[ChangeLog][QtQml][QQmlEngine] Added retranslate() slot and
QEvent::LanguageChange support to refresh bindings when changing the
language at run-time.

Task-number: QTBUG-15602
Change-Id: Ide174648e1d8a5738acb88e15495018d0869d7bc
Reviewed-by: Michael Brasser <michael.brasser@live.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/qml/qml/qqmljavascriptexpression_p.h b/src/qml/qml/qqmljavascriptexpression_p.h
index 646cc5ab3d..b540959331 100644
--- a/src/qml/qml/qqmljavascriptexpression_p.h
+++ b/src/qml/qml/qqmljavascriptexpression_p.h
@@ -160,11 +160,13 @@ protected:
     }
 
     void setupFunction(QV4::ExecutionContext *qmlContext, QV4::Function *f);
+    void setCompilationUnit(QV4::CompiledData::CompilationUnit *compilationUnit);
 
 private:
     friend class QQmlContextData;
     friend class QQmlPropertyCapture;
     friend void QQmlJavaScriptExpressionGuard_callback(QQmlNotifierEndpoint *, void **);
+    friend class QQmlTranslationBinding;
 
     QQmlDelayedError *m_error;