Fix inheritance of widget input contexts.

If a parent widget has an input context assigned return that from
QWidget::inputContext() before returning QApplication::inputContext().

Change-Id: I4982a91ace9b7485534f1c31fa4e2d549482640e
Task-number: QTBUG-17390
Reviewed-by: axis

3 files changed, 50 insertions, 4 deletions

diff --git a/src/gui/kernel/qwidget.cpp b/src/gui/kernel/qwidget.cpp
index e542a59..7065e85 100644
--- a/src/gui/kernel/qwidget.cpp
+++ b/src/gui/kernel/qwidget.cpp
@@ -393,11 +393,24 @@ void QWidgetPrivate::scrollChildren(int dx, int dy)
     }
 }
 
+QInputContext *QWidgetPrivate::assignedInputContext() const
+{
+#ifndef QT_NO_IM
+    const QWidget *widget = q_func();
+    while (widget) {
+        if (QInputContext *qic = widget->d_func()->ic)
+            return qic;
+        widget = widget->parentWidget();
+    }
+#endif
+    return 0;
+}
+
 QInputContext *QWidgetPrivate::inputContext() const
 {
 #ifndef QT_NO_IM
-    if (ic)
-        return ic;
+    if (QInputContext *qic = assignedInputContext())
+        return qic;
     return qApp->inputContext();
 #else
     return 0;
@@ -10721,7 +10734,7 @@ void QWidget::setAttribute(Qt::WidgetAttribute attribute, bool on)
     case Qt::WA_InputMethodEnabled: {
 #ifndef QT_NO_IM
         QWidget *focusWidget = d->effectiveFocusWidget();
-        QInputContext *ic = focusWidget->d_func()->ic;
+        QInputContext *ic = focusWidget->d_func()->assignedInputContext();
         if (!ic && (!on || hasFocus()))
             ic = focusWidget->d_func()->inputContext();
         if (ic) {
@@ -11208,7 +11221,7 @@ void QWidget::updateMicroFocus()
 #if !defined(QT_NO_IM) && (defined(Q_WS_X11) || defined(Q_WS_QWS) || defined(Q_OS_SYMBIAN))
     Q_D(QWidget);
     // and optimization to update input context only it has already been created.
-    if (d->ic || qApp->d_func()->inputContext) {
+    if (d->assignedInputContext() || qApp->d_func()->inputContext) {
         QInputContext *ic = inputContext();
         if (ic)
             ic->update();
diff --git a/src/gui/kernel/qwidget_p.h b/src/gui/kernel/qwidget_p.h
index 3759dd1..9f6ba6f 100644
--- a/src/gui/kernel/qwidget_p.h
+++ b/src/gui/kernel/qwidget_p.h
@@ -559,6 +559,7 @@ public:
     // sub-classes that their internals are about to be released.
     virtual void aboutToDestroy() {}
 
+    QInputContext *assignedInputContext() const;
     QInputContext *inputContext() const;
     inline QWidget *effectiveFocusWidget() {
         QWidget *w = q_func();
diff --git a/tests/auto/qinputcontext/tst_qinputcontext.cpp b/tests/auto/qinputcontext/tst_qinputcontext.cpp
index 800f9de..6a047f2 100644
--- a/tests/auto/qinputcontext/tst_qinputcontext.cpp
+++ b/tests/auto/qinputcontext/tst_qinputcontext.cpp
@@ -88,6 +88,7 @@ private slots:
     void closeSoftwareInputPanel();
     void selections();
     void focusProxy();
+    void contextInheritance();
     void symbianTestCoeFepInputContext_data();
     void symbianTestCoeFepInputContext();
     void symbianTestCoeFepAutoCommit_data();
@@ -473,6 +474,37 @@ void tst_QInputContext::focusProxy()
     QCOMPARE(gic->focusWidget(), &proxy);
 }
 
+void tst_QInputContext::contextInheritance()
+{
+    QWidget parent;
+    QWidget child(&parent);
+
+    parent.setAttribute(Qt::WA_InputMethodEnabled, true);
+    child.setAttribute(Qt::WA_InputMethodEnabled, true);
+
+    QCOMPARE(parent.inputContext(), qApp->inputContext());
+    QCOMPARE(child.inputContext(), qApp->inputContext());
+
+    QInputContext *qic = new QFilterInputContext;
+    parent.setInputContext(qic);
+    QCOMPARE(parent.inputContext(), qic);
+    QCOMPARE(child.inputContext(), qic);
+
+    parent.setAttribute(Qt::WA_InputMethodEnabled, false);
+    QVERIFY(!parent.inputContext());
+    QCOMPARE(child.inputContext(), qic);
+    parent.setAttribute(Qt::WA_InputMethodEnabled, true);
+
+    parent.setInputContext(0);
+    QCOMPARE(parent.inputContext(), qApp->inputContext());
+    QCOMPARE(child.inputContext(), qApp->inputContext());
+
+    qic = new QFilterInputContext;
+    qApp->setInputContext(qic);
+    QCOMPARE(parent.inputContext(), qic);
+    QCOMPARE(child.inputContext(), qic);
+}
+
 #ifdef QT_WEBKIT_LIB
 class AutoWebView : public QWebView
 {