Implement logout button

src/nexus.cpp

@@ -39,7 +39,8 @@ Nexus::~Nexus()
 #endif
     delete loginScreen;
     delete profile;
-    Settings::getInstance().save();
+    if (profile)
+        Settings::getInstance().save();
 }
 
 void Nexus::start()
@@ -68,12 +69,23 @@ void Nexus::start()
 
 void Nexus::showLogin()
 {
-    ((QApplication*)qApp)->setQuitOnLastWindowClosed(true);
+#ifdef Q_OS_ANDROID
+    delete androidui;
+    androidgui = nullptr;
+#else
+    delete widget;
+    widget = nullptr;
+#endif
+
+    delete profile;
+    profile = nullptr;
+
     loginScreen->reset();
 #ifndef Q_OS_ANDROID
     loginScreen->move(QApplication::desktop()->screen()->rect().center() - loginScreen->rect().center());
 #endif
     loginScreen->show();
+    ((QApplication*)qApp)->setQuitOnLastWindowClosed(true);
 }
 
 void Nexus::showMainGUI()

src/nexus.h

@@ -17,7 +17,7 @@ class Nexus : public QObject
     Q_OBJECT
 public:
     void start(); ///< Sets up invariants and calls showLogin
-    void showLogin(); ///< Shows the login screen
+    void showLogin(); ///< Hides the man GUI, delete the profile, and shows the login screen
     /// Hides the login screen and shows the GUI for the given profile.
     /// Will delete the current GUI, if it exists.
     void showMainGUI();

src/profile.cpp

@@ -66,6 +66,7 @@ Profile::~Profile()
 {
     delete core;
     delete coreThread;
+    ProfileLocker::assertLock();
     assert(ProfileLocker::getCurLockName() == name);
     ProfileLocker::unlock();
 }

src/widget/form/profileform.cpp

@@ -310,7 +310,10 @@ void ProfileForm::onDeleteClicked()
 
 void ProfileForm::onLogoutClicked()
 {
-    /// TODO: Save and call Nexus show login?
+    Nexus& nexus = Nexus::getInstance();
+    nexus.getProfile()->saveToxSave();
+    Settings::getInstance().save();
+    nexus.showLogin();
 }
 
 void ProfileForm::onCopyQrClicked()