Core: Simplify use of settings based on aspect containers

This effectively introduces a third parallel system for handling
IOptionPage apply() setup besides setWidgetCreator/IOptionsPageWidget
::apply() and the few remaining completely manual implementations of
IOptionPage::apply(), but there is some hope that this one can actually
replace all in a not so distant future.

Change-Id: I0c90a3a484216de9d7ad0f2f60c044c4e84dadb7
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/coreplugin/dialogs/ioptionspage.cpp

@@ -28,6 +28,9 @@
 
 #include "ioptionspage.h"
 
+#include <coreplugin/icore.h>
+
+#include <utils/aspects.h>
 #include <utils/stringutils.h>
 #include <utils/qtcassert.h>
 
@@ -121,9 +124,16 @@ void Core::IOptionsPage::setWidgetCreator(const WidgetCreator &widgetCreator)
 
 QWidget *Core::IOptionsPage::widget()
 {
-    QTC_ASSERT(m_widgetCreator, return nullptr);
+    if (!m_widget) {
-    if (!m_widget)
+        if (m_widgetCreator) {
-        m_widget = m_widgetCreator();
+            m_widget = m_widgetCreator();
+        } else if (m_layouter) {
+            m_widget = new QWidget;
+            m_layouter(m_widget);
+        } else {
+            QTC_CHECK(false);
+        }
+    }
     return m_widget;
 }
 
@@ -138,9 +148,14 @@ QWidget *Core::IOptionsPage::widget()
 
 void Core::IOptionsPage::apply()
 {
-    QTC_ASSERT(m_widgetCreator, return);
+    if (auto widget = qobject_cast<IOptionsPageWidget *>(m_widget)) {
-    if (m_widget)
+        widget->apply();
-        m_widget->apply();
+    } else if (m_settings) {
+        if (m_settings->isDirty()) {
+            m_settings->apply();
+            m_settings->writeSettings(Core::ICore::settings());
+         }
+    }
 }
 
 /*!
@@ -154,11 +169,12 @@ void Core::IOptionsPage::apply()
 
 void Core::IOptionsPage::finish()
 {
-    QTC_ASSERT(m_widgetCreator, return);
+    if (auto widget = qobject_cast<IOptionsPageWidget *>(m_widget))
-    if (m_widget) {
+        widget->finish();
-        m_widget->finish();
+    else if (m_settings)
-        delete m_widget;
+        m_settings->finish();
-    }
+
+    delete m_widget;
 }
 
 /*!
@@ -170,6 +186,16 @@ void Core::IOptionsPage::setCategoryIconPath(const QString &categoryIconPath)
     m_categoryIcon = Icon({{categoryIconPath, Theme::PanelTextColorDark}}, Icon::Tint);
 }
 
+void Core::IOptionsPage::setSettings(AspectContainer *settings)
+{
+    m_settings = settings;
+}
+
+void Core::IOptionsPage::setLayouter(const std::function<void(QWidget *w)> &layouter)
+{
+    m_layouter = layouter;
+}
+
 /*!
     \fn void Core::IOptionsPage::setId(Utils::Id id)
 

src/plugins/coreplugin/dialogs/ioptionspage.h

@@ -37,10 +37,13 @@
 
 #include <functional>
 
+namespace Utils { class AspectContainer; };
+
 namespace Core {
 
 class CORE_EXPORT IOptionsPageWidget : public QWidget
 {
+    Q_OBJECT
 public:
     virtual void apply() = 0;
     virtual void finish() {}
@@ -77,6 +80,8 @@ protected:
     void setDisplayCategory(const QString &displayCategory) { m_displayCategory = displayCategory; }
     void setCategoryIcon(const Utils::Icon &categoryIcon) { m_categoryIcon = categoryIcon; }
     void setCategoryIconPath(const QString &categoryIconPath);
+    void setSettings(Utils::AspectContainer *settings);
+    void setLayouter(const std::function<void(QWidget *w)> &layouter);
 
     Utils::Id m_id;
     Utils::Id m_category;
@@ -84,10 +89,13 @@ protected:
     QString m_displayCategory;
     Utils::Icon m_categoryIcon;
     WidgetCreator m_widgetCreator;
-    QPointer<IOptionsPageWidget> m_widget; // Used in conjunction with m_widgetCreator
+    QPointer<QWidget> m_widget; // Used in conjunction with m_widgetCreator
 
     mutable bool m_keywordsInitialized = false;
     mutable QStringList m_keywords;
+
+    Utils::AspectContainer *m_settings = nullptr;
+    std::function<void(QWidget *w)> m_layouter;
 };
 
 /*