Fix possible crash in PlatformInputContext::update

Under some condition, QPlatformInputContext::update is called before
our (QML) input context is created. This will result in crash if
desktop integration is also enabled, since null pointer check is
missing.

[ChangeLog] Fixed possible crash in PlatformInputContext::update.

Task-number: QTBUG-67595
Change-Id: I19c78dbf19cf3c2a72193c2e2a60f46995c1f6ad
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 9 insertions, 10 deletions

diff --git a/src/virtualkeyboard/platforminputcontext.cpp b/src/virtualkeyboard/platforminputcontext.cpp
index 6d555160..8b5ce99b 100644
--- a/src/virtualkeyboard/platforminputcontext.cpp
+++ b/src/virtualkeyboard/platforminputcontext.cpp
@@ -84,18 +84,17 @@ void PlatformInputContext::commit()
 void PlatformInputContext::update(Qt::InputMethodQueries queries)
 {
     VIRTUALKEYBOARD_DEBUG() << "PlatformInputContext::update():" << queries;
-    bool enabled = inputMethodQuery(Qt::ImEnabled).toBool();
-#ifdef QT_VIRTUALKEYBOARD_DESKTOP
-    if (enabled && !m_inputPanel) {
-        m_inputPanel = new DesktopInputPanel(this);
-        m_inputPanel->createView();
-        m_selectionControl = new DesktopInputSelectionControl(this, m_inputContext);
-        m_selectionControl->createHandles();
-    }
-#endif
-
     if (m_inputContext) {
+        bool enabled = inputMethodQuery(Qt::ImEnabled).toBool();
         if (enabled) {
+#ifdef QT_VIRTUALKEYBOARD_DESKTOP
+            if (!m_inputPanel) {
+                m_inputPanel = new DesktopInputPanel(this);
+                m_inputPanel->createView();
+                m_selectionControl = new DesktopInputSelectionControl(this, m_inputContext);
+                m_selectionControl->createHandles();
+            }
+#endif
             m_inputContext->update(queries);
             if (m_visible)
                 updateInputPanelVisible();