settings: Add SettingsCategory class

Add a new category class for settings. This will eventually allow
category classes to maintain their own lists of subpages.

src/CMakeLists.txt

@@ -363,6 +363,7 @@ set(SOURCES
   ui/playbacksettingspage.cpp
   ui/qtsystemtrayicon.cpp
   ui/screensaver.cpp
+  ui/settingscategory.cpp
   ui/settingsdialog.cpp
   ui/settingspage.cpp
   ui/splash.cpp
@@ -659,6 +660,7 @@ set(HEADERS
   ui/organiseerrordialog.h
   ui/playbacksettingspage.h
   ui/qtsystemtrayicon.h
+  ui/settingscategory.h
   ui/settingsdialog.h
   ui/settingspage.h
   ui/standarditemiconloader.h

src/ui/settingscategory.cpp

@@ -0,0 +1,25 @@
+/* This file is part of Clementine.
+   Copyright 2021, Jim Broadus <jbroadus@gmail.com>
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "settingscategory.h"
+
+SettingsCategory::SettingsCategory(const QString& name, SettingsDialog* dialog)
+    : dialog_(dialog) {
+  setText(0, name);
+  setData(0, SettingsDialog::Role_IsSeparator, true);
+  setFlags(Qt::ItemIsEnabled);
+}

src/ui/settingscategory.h

@@ -0,0 +1,33 @@
+/* This file is part of Clementine.
+   Copyright 2021, Jim Broadus <jbroadus@gmail.com>
+
+   Clementine is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   Clementine is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Clementine.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef SETTINGSCATEGORY_H
+#define SETTINGSCATEGORY_H
+
+#include <QTreeWidgetItem>
+
+#include "settingsdialog.h"
+
+class SettingsCategory : public QTreeWidgetItem {
+ public:
+  SettingsCategory(const QString& name, SettingsDialog* dialog);
+
+ protected:
+  SettingsDialog* dialog_;
+};
+
+#endif  // SETTINGSCATEGORY_H

src/ui/settingsdialog.cpp

@@ -44,6 +44,7 @@
 #include "notificationssettingspage.h"
 #include "playbacksettingspage.h"
 #include "playlist/playlistview.h"
+#include "settingscategory.h"
 #include "songinfo/songinfosettingspage.h"
 #include "transcoder/transcodersettingspage.h"
 #include "ui_settingsdialog.h"
@@ -134,8 +135,8 @@ SettingsDialog::SettingsDialog(Application* app, BackgroundStreams* streams,
   ui_->setupUi(this);
   ui_->list->setItemDelegate(new SettingsItemDelegate(this));
 
-  QTreeWidgetItem* general = AddCategory(tr("General"));
-
+  SettingsCategory* general = new SettingsCategory(tr("General"), this);
+  AddCategory(general);
   AddPage(Page_Playback, new PlaybackSettingsPage(this), general);
   AddPage(Page_Behaviour, new BehaviourSettingsPage(this), general);
   AddPage(Page_Library, new LibrarySettingsPage(this), general);
@@ -153,7 +154,8 @@ SettingsDialog::SettingsDialog(Application* app, BackgroundStreams* streams,
 #endif
 
   // User interface
-  QTreeWidgetItem* iface = AddCategory(tr("User interface"));
+  SettingsCategory* iface = new SettingsCategory(tr("User interface"), this);
+  AddCategory(iface);
   AddPage(Page_GlobalShortcuts, new GlobalShortcutsSettingsPage(this), iface);
   AddPage(Page_GlobalSearch, new GlobalSearchSettingsPage(this), iface);
   AddPage(Page_Appearance, new AppearanceSettingsPage(this), iface);
@@ -169,7 +171,9 @@ SettingsDialog::SettingsDialog(Application* app, BackgroundStreams* streams,
   AddPage(Page_InternetShow, new InternetShowSettingsPage(this), iface);
 
   // Internet providers
-  QTreeWidgetItem* providers = AddCategory(tr("Internet providers"));
+  SettingsCategory* providers =
+      new SettingsCategory(tr("Internet providers"), this);
+  AddCategory(providers);
 
 #ifdef HAVE_LIBLASTFM
   AddPage(Page_Lastfm, new LastFMSettingsPage(this), providers);
@@ -228,16 +232,10 @@ SettingsDialog::SettingsDialog(Application* app, BackgroundStreams* streams,
 
 SettingsDialog::~SettingsDialog() { delete ui_; }
 
-QTreeWidgetItem* SettingsDialog::AddCategory(const QString& name) {
-  QTreeWidgetItem* item = new QTreeWidgetItem;
-  item->setText(0, name);
-  item->setData(0, Role_IsSeparator, true);
-  item->setFlags(Qt::ItemIsEnabled);
-
-  ui_->list->invisibleRootItem()->addChild(item);
-  item->setExpanded(true);
-
-  return item;
+void SettingsDialog::AddCategory(SettingsCategory* category) {
+  ui_->list->invisibleRootItem()->addChild(category);
+  // This must not be called before it's added to the parent.
+  category->setExpanded(true);
 }
 
 void SettingsDialog::AddPage(Page id, SettingsPage* page,

src/ui/settingsdialog.h

@@ -49,6 +49,8 @@ class SettingsItemDelegate : public QStyledItemDelegate {
              const QModelIndex& index) const;
 };
 
+class SettingsCategory;
+
 class SettingsDialog : public QDialog {
   Q_OBJECT
 
@@ -131,7 +133,7 @@ class SettingsDialog : public QDialog {
     SettingsPage* page_;
   };
 
-  QTreeWidgetItem* AddCategory(const QString& name);
+  void AddCategory(SettingsCategory* category);
   void AddPage(Page id, SettingsPage* page, QTreeWidgetItem* parent = nullptr);
 
  private: