ProjectExplorer: Make sure the target setup page does not persist

The TargetSetupPage is not designed to stay around after setupProject()
has been called. So let's throw it away in the TargetSetupPageWrapper
and create a new one on demand.

Fixes: QTCREATORBUG-21242
Change-Id: I1d6f4214e7bfdfef9d58593007728612642b90d6
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/projectexplorer/targetsettingspanel.cpp

@@ -80,6 +80,12 @@ class TargetSetupPageWrapper : public QWidget
 public:
     explicit TargetSetupPageWrapper(Project *project);
 
+    void ensureSetupPage()
+    {
+        if (!m_targetSetupPage)
+            addTargetSetupPage();
+    }
+
 protected:
     void keyReleaseEvent(QKeyEvent *event) override
     {
@@ -91,22 +97,22 @@ protected:
     {
         if (event->key() == Qt::Key_Return || event->key() == Qt::Key_Enter) {
             event->accept();
-            done();
+            if (m_targetSetupPage)
+                done();
         }
     }
 
 private:
     void done()
     {
+        QTC_ASSERT(m_targetSetupPage, return);
+        m_targetSetupPage->disconnect();
         m_targetSetupPage->setupProject(m_project);
+        m_targetSetupPage->deleteLater();
+        m_targetSetupPage = nullptr;
         Core::ModeManager::activateMode(Core::Constants::MODE_EDIT);
     }
 
-    void cancel()
-    {
-        ProjectExplorerPlugin::unloadProject(m_project);
-    }
-
     void kitUpdated(ProjectExplorer::Kit *k)
     {
         if (k == KitManager::defaultKit())
@@ -115,29 +121,21 @@ private:
 
     void completeChanged()
     {
-        m_configureButton->setEnabled(m_targetSetupPage->isComplete());
+        m_configureButton->setEnabled(m_targetSetupPage && m_targetSetupPage->isComplete());
     }
 
     void updateNoteText();
+    void addTargetSetupPage();
 
-    Project *m_project;
+    Project * const m_project;
-    TargetSetupPage *m_targetSetupPage;
+    TargetSetupPage *m_targetSetupPage = nullptr;
-    QPushButton *m_configureButton;
+    QPushButton *m_configureButton = nullptr;
+    QVBoxLayout *m_setupPageContainer = nullptr;
 };
 
 TargetSetupPageWrapper::TargetSetupPageWrapper(Project *project)
     : m_project(project)
 {
-    m_targetSetupPage = new TargetSetupPage(this);
-    m_targetSetupPage->setUseScrollArea(false);
-    m_targetSetupPage->setProjectPath(project->projectFilePath().toString());
-    m_targetSetupPage->setRequiredKitPredicate(project->requiredKitPredicate());
-    m_targetSetupPage->setPreferredKitPredicate(project->preferredKitPredicate());
-    m_targetSetupPage->setProjectImporter(project->projectImporter());
-    m_targetSetupPage->initializePage();
-    m_targetSetupPage->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
-    updateNoteText();
-
     auto box = new QDialogButtonBox(this);
 
     m_configureButton = new QPushButton(this);
@@ -150,20 +148,13 @@ TargetSetupPageWrapper::TargetSetupPageWrapper(Project *project)
 
     auto layout = new QVBoxLayout(this);
     layout->setMargin(0);
-    layout->addWidget(m_targetSetupPage);
+    m_setupPageContainer = new QVBoxLayout;
+    layout->addLayout(m_setupPageContainer);
     layout->addLayout(hbox);
     layout->addStretch(10);
-
     completeChanged();
-
     connect(m_configureButton, &QAbstractButton::clicked,
             this, &TargetSetupPageWrapper::done);
-    connect(m_targetSetupPage, &QWizardPage::completeChanged,
-            this, &TargetSetupPageWrapper::completeChanged);
-    connect(KitManager::instance(), &KitManager::defaultkitChanged,
-            this, &TargetSetupPageWrapper::updateNoteText);
-    connect(KitManager::instance(), &KitManager::kitUpdated,
-            this, &TargetSetupPageWrapper::kitUpdated);
 }
 
 void TargetSetupPageWrapper::updateNoteText()
@@ -198,6 +189,29 @@ void TargetSetupPageWrapper::updateNoteText()
     m_targetSetupPage->showOptionsHint(showHint);
 }
 
+void TargetSetupPageWrapper::addTargetSetupPage()
+{
+    m_targetSetupPage = new TargetSetupPage(this);
+    m_targetSetupPage->setUseScrollArea(false);
+    m_targetSetupPage->setProjectPath(m_project->projectFilePath().toString());
+    m_targetSetupPage->setRequiredKitPredicate(m_project->requiredKitPredicate());
+    m_targetSetupPage->setPreferredKitPredicate(m_project->preferredKitPredicate());
+    m_targetSetupPage->setProjectImporter(m_project->projectImporter());
+    m_targetSetupPage->initializePage();
+    m_targetSetupPage->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
+    m_setupPageContainer->addWidget(m_targetSetupPage);
+    updateNoteText();
+
+    completeChanged();
+
+    connect(m_targetSetupPage, &QWizardPage::completeChanged,
+            this, &TargetSetupPageWrapper::completeChanged);
+    connect(KitManager::instance(), &KitManager::defaultkitChanged,
+            this, &TargetSetupPageWrapper::updateNoteText);
+    connect(KitManager::instance(), &KitManager::kitUpdated,
+            this, &TargetSetupPageWrapper::kitUpdated);
+}
+
 //
 // TargetSettingsPanelItem
 //
@@ -228,6 +242,7 @@ public:
     QPointer<QWidget> m_noKitLabel;
     QPointer<QWidget> m_configurePage;
     QPointer<QWidget> m_configuredPage;
+    TargetSetupPageWrapper *m_targetSetupPageWrapper = nullptr;
 };
 
 void TargetGroupItemPrivate::ensureWidget()
@@ -253,12 +268,13 @@ void TargetGroupItemPrivate::ensureWidget()
     }
 
     if (!m_configurePage) {
-        auto widget = new TargetSetupPageWrapper(m_project);
+        m_targetSetupPageWrapper = new TargetSetupPageWrapper(m_project);
         m_configurePage = new PanelsWidget(tr("Configure Project"),
                                            QIcon(":/projectexplorer/images/unconfigured.png"),
-                                           widget);
+                                           m_targetSetupPageWrapper);
-        m_configurePage->setFocusProxy(widget);
+        m_configurePage->setFocusProxy(m_targetSetupPageWrapper);
     }
+    m_targetSetupPageWrapper->ensureSetupPage();
 
     if (!m_configuredPage) {
         auto widget = new QWidget;