ProjectExplorer: Rework mode main window

The existing solution with the special-style horizontal
kit selector comes from a time when there was typically
one, at most four targets. Today's setup can easily
reach half a dozen targets with several toolchain versions
each and can't be sensibly handled with the overflowing
horizontal bar.

This here replaces the horizontal kit selector bar as
well as the top level project "tab bar" with a normal
tree view. All targets are visible (but possibly disabled)
at once, and can be enabled/disabled using the context
menu on the tree items.

Change-Id: I1ce7401ca96109bf34bc8c0ae19d265e5845aa88
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/projectexplorer/projectwindow.h

@@ -27,78 +27,59 @@
 
 #include "projectexplorer_export.h"
 
-#include <QMap>
+#include <QPointer>
 #include <QWidget>
 
+#include <utils/fancymainwindow.h>
+
 QT_BEGIN_NAMESPACE
-class QStackedWidget;
+class QComboBox;
 QT_END_NAMESPACE
 
 namespace ProjectExplorer {
+
 class Project;
 class Target;
 
 namespace Internal {
 
-class DoubleTabWidget;
+class SelectorModel;
+class SelectorTree;
+class ProjectItem;
 
-class WidgetCache
-{
-public:
-    void registerProject(Project *project);
-    QVector<QWidget *> deregisterProject(Project *project);
+enum {
+    ContextMenuItemAdderRole // To augment a context menu, data has a QMenu*
+        = Qt::UserRole + 1,
+    ItemActivaterRole,       // This item got activated and is now responsible for the central widget
+    ActiveWidgetRole,        // This item's widget to be shown as central widget.
+    ActiveIndexRole,          // This is the index of the currently selected item in the tree view
 
-    bool isRegistered(Project *project) const;
-    int indexForProject(Project *project) const;
-    Project *projectFor(int projectIndex) const;
-    QStringList tabNames(Project *project) const;
-
-    QWidget *widgetFor(Project *project, int factoryIndex);
-
-    void sort();
-    int recheckFactories(Project *project, int oldSupportsIndex);
-
-    void clear();
-
-private:
-    int factoryIndex(int projectIndex, int supportsIndex) const;
-
-    class ProjectInfo
-    {
-    public:
-        Project *project;
-        QVector<bool> supports;
-        QVector<QWidget *> widgets;
-    };
-    QList<ProjectInfo> m_projects; //ordered by displaynames of the projects
+    ProjectDisplayNameRole   // Shown in the project selection combobox
 };
 
-class ProjectWindow : public QWidget
+class ProjectWindow : public Utils::FancyMainWindow
 {
     Q_OBJECT
 
 public:
-    explicit ProjectWindow(QWidget *parent = nullptr);
-
-    void aboutToShutdown();
-
-    void projectUpdated(Project *project);
+    ProjectWindow();
 
 private:
-    void projectDisplayNameChanged(Project *p);
-    void showProperties(int index, int subIndex);
-    void registerProject(Project*);
-    bool deregisterProject(Project*);
-    void startupProjectChanged(Project *);
-    void removedTarget(Target*);
+    void contextMenuEvent(QContextMenuEvent *event) override;
 
-    void removeCurrentWidget();
+    void updatePanel();
+    void openContextMenu(const QPoint &pos);
+    void registerProject(Project *project);
+    void deregisterProject(Project *project);
+    void startupProjectChanged(Project *project);
+    void projectSelected(int index);
+    void itemActivated(const QModelIndex &index);
+    ProjectItem *itemForProject(Project *project) const;
 
-    bool m_ignoreChange;
-    DoubleTabWidget *m_tabWidget;
-    QStackedWidget *m_centralWidget;
-    QWidget *m_currentWidget;
-    WidgetCache m_cache;
+    SelectorModel *m_selectorModel;
+    SelectorTree *m_selectorTree;
+    QDockWidget *m_selectorDock;
+    QComboBox *m_projectSelection;
 };
 
 } // namespace Internal