Fix crash on program exit. Always good to use defensive programming techniques...

git-svn-id: http://svn.haiku-os.org/webpositive/webkit/trunk@225 94f232f2-1747-11df-bad5-a5bfde151594

src/apps/webpositive/LauncherWindow.cpp

@@ -353,13 +353,22 @@ void LauncherWindow::MessageReceived(BMessage* message)
     }
 
     case TAB_CHANGED: {
-        int32 index = message->FindInt32("index");
+    	// This message may be received also when the last tab closed, i.e. with index == -1.
-        SetCurrentWebView(dynamic_cast<BWebView*>(m_tabView->ViewForTab(index)));
+        int32 index = -1;
-        updateTitle(m_tabView->TabAt(index)->Label());
+        message->FindInt32("index", &index);
-        m_url->SetText(CurrentWebView()->MainFrameURL());
+        BWebView* webView = dynamic_cast<BWebView*>(m_tabView->ViewForTab(index));
-        // Trigger update of the interface to the new page, by requesting
+        SetCurrentWebView(webView);
-        // to resend all notifications.
+        BTab* tab = m_tabView->TabAt(index);
-        CurrentWebView()->WebPage()->ResendNotifications();
+        if (tab)
+            updateTitle(tab->Label());
+        else
+            updateTitle("");
+        if (webView) {
+            m_url->SetText(webView->MainFrameURL());
+            // Trigger update of the interface to the new page, by requesting
+            // to resend all notifications.
+            webView->WebPage()->ResendNotifications();
+        }
         break;
     }