Debugger: Start introducing dynamic perspectives

Make perspectives and tool bars destroyable. This is a
step forward to multiply debugger engines whose perspective's
life time is connected to the engine, not the debug mode.

In the present setup there are two kind of perspective:
1 - static: with a lifetime associated to the application
(or, rather, plugin that defines them). These are listed
in the perspective chooser, later e.g. Debugger for
pre-set breakpoints
2 - dynamic: with a shorted lifetime, e.g. running GDB engine.

Presently, and possibly also in future so, a dynamic
perspective is related to exactly one of the static
perspectives, i.e. are kind of "child".

Change-Id: Ic11572e7121e14f8da2927a0c0ac3441c99073a3
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/debugger/analyzer/analyzermanager.h

@@ -63,8 +63,10 @@ DEBUGGER_EXPORT void showCannotStartDialog(const QString &toolName);
 
 // Register a tool for a given start mode.
 DEBUGGER_EXPORT void registerPerspective(const QByteArray &perspectiveId, const Utils::Perspective *perspective);
+DEBUGGER_EXPORT void destroyDynamicPerspective(const QByteArray &perspectiveId);
 DEBUGGER_EXPORT void setPerspectiveEnabled(const QByteArray &perspectiveId, bool enable);
 DEBUGGER_EXPORT void registerToolbar(const QByteArray &perspectiveId, const Utils::ToolbarDescription &desc);
+DEBUGGER_EXPORT void destroyDynamicToolbar(const QByteArray &perspectiveId);
 
 DEBUGGER_EXPORT void enableMainWindow(bool on);
 DEBUGGER_EXPORT QWidget *mainWindow();

src/plugins/debugger/debuggermainwindow.cpp

@@ -103,10 +103,18 @@ DebuggerMainWindow::~DebuggerMainWindow()
 void DebuggerMainWindow::registerPerspective(const QByteArray &perspectiveId, const Perspective *perspective)
 {
     m_perspectiveForPerspectiveId.insert(perspectiveId, perspective);
+    QByteArray parentPerspective = perspective->parentPerspective();
+    // Add "main" perspectives to the chooser.
+    if (parentPerspective.isEmpty()) {
         m_perspectiveChooser->addItem(perspective->name(), perspectiveId);
-    // adjust width if necessary
+        increaseChooserWidthIfNecessary(perspective->name());
+    }
+}
+
+void DebuggerMainWindow::increaseChooserWidthIfNecessary(const QString &visibleName)
+{
     const int oldWidth = m_perspectiveChooser->width();
-    const int contentWidth = m_perspectiveChooser->fontMetrics().width(perspective->name());
+    const int contentWidth = m_perspectiveChooser->fontMetrics().width(visibleName);
     QStyleOptionComboBox option;
     option.initFrom(m_perspectiveChooser);
     const QSize sz(contentWidth, 1);
@@ -116,12 +124,35 @@ void DebuggerMainWindow::registerPerspective(const QByteArray &perspectiveId, co
         m_perspectiveChooser->setFixedWidth(width);
 }
 
+void DebuggerMainWindow::destroyDynamicPerspective(const QByteArray &perspectiveId)
+{
+    savePerspectiveHelper(perspectiveId);
+
+    const Perspective *perspective = m_perspectiveForPerspectiveId.take(perspectiveId);
+    QTC_ASSERT(perspective, return);
+    // Dynamic perspectives are currently not visible in the chooser.
+    // This might change in the future, make sure we notice.
+    const int idx = m_perspectiveChooser->findData(perspectiveId);
+    QTC_ASSERT(idx == -1, m_perspectiveChooser->removeItem(idx));
+    QByteArray parentPerspective = perspective->parentPerspective();
+    delete perspective;
+    // All dynamic perspectives currently have a static parent perspective.
+    // This might change in the future, make sure we notice.
+    QTC_CHECK(!parentPerspective.isEmpty());
+    restorePerspective(parentPerspective);
+}
+
 void DebuggerMainWindow::registerToolbar(const QByteArray &perspectiveId, QWidget *widget)
 {
     m_toolbarForPerspectiveId.insert(perspectiveId, widget);
     m_controlsStackWidget->addWidget(widget);
 }
 
+void DebuggerMainWindow::destroyDynamicToolbar(const QByteArray &perspectiveId)
+{
+    delete m_toolbarForPerspectiveId.take(perspectiveId);
+}
+
 void DebuggerMainWindow::showStatusMessage(const QString &message, int timeoutMS)
 {
     m_statusLabel->showStatusMessage(message, timeoutMS);
@@ -456,6 +487,16 @@ void Perspective::aboutToActivate() const
         m_aboutToActivateCallback();
 }
 
+QByteArray Perspective::parentPerspective() const
+{
+    return m_parentPerspective;
+}
+
+void Perspective::setParentPerspective(const QByteArray &parentPerspective)
+{
+    m_parentPerspective = parentPerspective;
+}
+
 QList<QWidget *> ToolbarDescription::widgets() const
 {
     return m_widgets;

src/plugins/debugger/debuggermainwindow.h

@@ -92,11 +92,15 @@ public:
     void setAboutToActivateCallback(const Callback &cb);
     void aboutToActivate() const;
 
+    QByteArray parentPerspective() const;
+    void setParentPerspective(const QByteArray &parentPerspective);
+
 private:
     Perspective(const Perspective &) = delete;
     void operator=(const Perspective &) = delete;
 
     QString m_name;
+    QByteArray m_parentPerspective;
     QVector<QByteArray> m_docks;
     QVector<Operation> m_operations;
     QPointer<QWidget> m_centralWidget;
@@ -127,7 +131,9 @@ public:
     ~DebuggerMainWindow() override;
 
     void registerPerspective(const QByteArray &perspectiveId, const Perspective *perspective);
+    void destroyDynamicPerspective(const QByteArray &perspectiveId);
     void registerToolbar(const QByteArray &perspectiveId, QWidget *widget);
+    void destroyDynamicToolbar(const QByteArray &perspectiveId);
 
     void resetCurrentPerspective();
     void restorePerspective(const QByteArray &perspectiveId);
@@ -150,6 +156,7 @@ private:
     QDockWidget *registerDockWidget(const QByteArray &dockId, QWidget *widget);
     void loadPerspectiveHelper(const QByteArray &perspectiveId, bool fromStoredSettings = true);
     void savePerspectiveHelper(const QByteArray &perspectiveId);
+    void increaseChooserWidthIfNecessary(const QString &visibleName);
 
     QByteArray m_currentPerspectiveId;
     QComboBox *m_perspectiveChooser;

src/plugins/debugger/debuggerplugin.cpp

@@ -3494,6 +3494,11 @@ void registerToolbar(const QByteArray &perspectiveId, const ToolbarDescription &
     dd->m_mainWindow->registerToolbar(perspectiveId, toolbar);
 }
 
+void destroyDynamicToolbar(const QByteArray &perspectiveId)
+{
+    dd->m_mainWindow->destroyDynamicToolbar(perspectiveId);
+}
+
 QAction *createStartAction()
 {
     auto action = new QAction(DebuggerMainWindow::tr("Start"), DebuggerPlugin::instance());
@@ -3515,6 +3520,11 @@ void registerPerspective(const QByteArray &perspectiveId, const Perspective *per
     dd->m_mainWindow->registerPerspective(perspectiveId, perspective);
 }
 
+void destroyDynamicPerspective(const QByteArray &perspectiveId)
+{
+    dd->m_mainWindow->destroyDynamicPerspective(perspectiveId);
+}
+
 void setPerspectiveEnabled(const QByteArray &perspectiveId, bool enabled)
 {
     dd->m_mainWindow->setPerspectiveEnabled(perspectiveId, enabled);