From 5344bf1619e7ec9c39ec1d9c18e813305426728c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Thu, 2 Jun 2016 15:25:31 +0200
Subject: [PATCH] [plugins/qpa] Handle case that qtvirtualkeyboard plugin is
 not available more gracefully

We didn't check whether creating the QPlatfromInputContext worked and
accessed the m_inputContext unconditionally which obviously crashed.

Now the connects related to QInputMethods are not setup if we failed
to create the QPlatfromInputContext.

Reviewed-By: bshah
---
 plugins/qpa/integration.cpp | 44 +++++++++++++++++++------------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/plugins/qpa/integration.cpp b/plugins/qpa/integration.cpp
index 41b47eeeef..90802e59a7 100644
--- a/plugins/qpa/integration.cpp
+++ b/plugins/qpa/integration.cpp
@@ -97,29 +97,31 @@ void Integration::initialize()
     screenAdded(m_dummyScreen);
     m_inputContext.reset(QPlatformInputContextFactory::create(QStringLiteral("qtvirtualkeyboard")));
     qunsetenv("QT_IM_MODULE");
-    connect(qApp, &QGuiApplication::focusObjectChanged, this,
-        [this] {
-            if (VirtualKeyboard::self() && qApp->focusObject() != VirtualKeyboard::self()) {
-                m_inputContext->setFocusObject(VirtualKeyboard::self());
-            }
-        }
-    );
-    connect(kwinApp(), &Application::workspaceCreated, this,
-        [this] {
-            if (VirtualKeyboard::self()) {
-                m_inputContext->setFocusObject(VirtualKeyboard::self());
-            }
-        }
-    );
-    connect(qApp->inputMethod(), &QInputMethod::visibleChanged, this,
-        [this] {
-            if (qApp->inputMethod()->isVisible()) {
-                if (QWindow *w = VirtualKeyboard::self()->inputPanel()) {
-                    QWindowSystemInterface::handleWindowActivated(w, Qt::ActiveWindowFocusReason);
+    if (!m_inputContext.isNull()) {
+        connect(qApp, &QGuiApplication::focusObjectChanged, this,
+            [this] {
+                if (VirtualKeyboard::self() && qApp->focusObject() != VirtualKeyboard::self()) {
+                    m_inputContext->setFocusObject(VirtualKeyboard::self());
                 }
             }
-        }
-    );
+        );
+        connect(kwinApp(), &Application::workspaceCreated, this,
+            [this] {
+                if (VirtualKeyboard::self()) {
+                    m_inputContext->setFocusObject(VirtualKeyboard::self());
+                }
+            }
+        );
+        connect(qApp->inputMethod(), &QInputMethod::visibleChanged, this,
+            [this] {
+                if (qApp->inputMethod()->isVisible()) {
+                    if (QWindow *w = VirtualKeyboard::self()->inputPanel()) {
+                        QWindowSystemInterface::handleWindowActivated(w, Qt::ActiveWindowFocusReason);
+                    }
+                }
+            }
+        );
+    }
 }
 
 QAbstractEventDispatcher *Integration::createEventDispatcher() const