Debugger: Simplify thread switching more

This moves the thread switcher combobox, the only consumer
of part of the threadhandler interface, into the threadhandler.

Change-Id: Icafd72e7777fad9196ce8fb33a79cae26c29a521
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/debugger/cdb/cdbengine.cpp

@@ -1496,7 +1496,7 @@ void CdbEngine::requestModuleSymbols(const QString &moduleName)
 
 void CdbEngine::reloadRegisters()
 {
-    if (!(threadsHandler()->currentThreadIndex() >= 0))
+    if (!threadsHandler()->currentThread())
         return;
     runCommand({"registers", ExtensionCommand, CB(handleRegistersExt)});
 }

src/plugins/debugger/debuggerengine.cpp

@@ -394,12 +394,6 @@ public:
         m_toolTipManager.resetLocation();
     }
 
-    void selectThread(int index)
-    {
-        const Thread thread = m_engine->threadsHandler()->rootItem()->childAt(index);
-        m_engine->doSelectThread(thread);
-    }
-
     void handleOperateByInstructionTriggered(bool on)
     {
         // Go to source only if we have the file.
@@ -485,7 +479,6 @@ public:
     QPointer<LocalsAndInspectorWindow> m_localsAndInspectorWindow;
 
     QPointer<QLabel> m_threadLabel;
-    QPointer<QComboBox> m_threadBox;
 
     bool m_busy = false;
     bool m_isDying = false;
@@ -746,14 +739,7 @@ void DebuggerEnginePrivate::setupViews()
 
     m_threadLabel = new QLabel(tr("Threads:"));
     m_perspective->addToolBarWidget(m_threadLabel);
-
-    m_threadBox = new QComboBox;
-    m_threadBox->setSizeAdjustPolicy(QComboBox::AdjustToContents);
-    m_threadBox->setModel(m_threadsHandler.model());
-    connect(m_threadBox, static_cast<void(QComboBox::*)(int)>(&QComboBox::activated),
-            this, &DebuggerEnginePrivate::selectThread);
-
-    m_perspective->addToolBarWidget(m_threadBox);
+    m_perspective->addToolBarWidget(m_threadsHandler.threadSwitcher());
 
     connect(TextEditorSettings::instance(), &TextEditorSettings::fontSettingsChanged,
             this, [this](const FontSettings &settings) {
@@ -1321,8 +1307,6 @@ void DebuggerEnginePrivate::updateState(bool alsoUpdateCompanion)
 {
     if (!m_perspective)
         return;
-    QTC_ASSERT(m_threadBox, return);
-    m_threadBox->setCurrentIndex(m_threadsHandler.currentThreadIndex());
 
     const DebuggerState state = m_state;
     const bool companionPreventsAction = m_engine->companionPreventsActions();
@@ -1410,8 +1394,9 @@ void DebuggerEnginePrivate::updateState(bool alsoUpdateCompanion)
     m_attachToCoreAction.setEnabled(true);
     m_attachToRemoteServerAction.setEnabled(true);
 
-    m_threadBox->setEnabled(state == InferiorStopOk || state == InferiorUnrunnable);
-    m_threadLabel->setEnabled(m_threadBox->isEnabled());
+    const bool threadsEnabled = state == InferiorStopOk || state == InferiorUnrunnable;
+    m_threadsHandler.threadSwitcher()->setEnabled(threadsEnabled);
+    m_threadLabel->setEnabled(threadsEnabled);
 
     const bool isCore = m_engine->runParameters().startMode == AttachCore;
     const bool stopped = state == InferiorStopOk;
@@ -2078,16 +2063,6 @@ void DebuggerEngine::assignValueInDebugger(WatchItem *,
 {
 }
 
-void DebuggerEngine::doSelectThread(const Thread &thread)
-{
-    QTC_ASSERT(thread, return);
-    // For immediate visual feedback.
-    d->m_threadsHandler.setCurrentThread(thread);
-    d->m_threadBox->setCurrentIndex(d->m_threadsHandler.currentThreadIndex());
-    // Initiate the actual switching in the debugger backend.
-    selectThread(thread);
-}
-
 void DebuggerEngine::handleRecordReverse(bool record)
 {
     executeRecordReverse(record);

src/plugins/debugger/debuggerengine.h

@@ -317,7 +317,6 @@ public:
     virtual void assignValueInDebugger(WatchItem *item,
         const QString &expr, const QVariant &value);
     virtual void selectThread(const Internal::Thread &thread) = 0;
-    void doSelectThread(const Internal::Thread &thread);
 
     virtual void executeRecordReverse(bool) {}
     virtual void executeReverse(bool) {}

src/plugins/debugger/threadshandler.cpp

@@ -221,6 +221,13 @@ ThreadsHandler::ThreadsHandler(DebuggerEngine *engine)
                   tr("Address"), tr("Function"), tr("File"), tr("Line"), tr("State"),
                   tr("Name"), tr("Target ID"), tr("Details"), tr("Core"),
               });
+
+    m_comboBox = new QComboBox;
+    m_comboBox->setSizeAdjustPolicy(QComboBox::AdjustToContents);
+    m_comboBox->setModel(this);
+    connect(m_comboBox, QOverload<int>::of(&QComboBox::activated), this, [this](int row) {
+        setData(index(row, 0), {}, BaseTreeView::ItemActivatedRole);
+    });
 }
 
 QVariant ThreadsHandler::data(const QModelIndex &index, int role) const
@@ -240,8 +247,11 @@ bool ThreadsHandler::setData(const QModelIndex &idx, const QVariant &data, int r
 {
     if (role == BaseTreeView::ItemActivatedRole) {
         const Thread thread = itemForIndexAtLevel<1>(idx);
-        if (thread != m_currentThread)
-            m_engine->doSelectThread(thread);
+        if (thread != m_currentThread) {
+            m_currentThread = thread;
+            m_comboBox->setCurrentIndex(idx.row());
+            m_engine->selectThread(thread);
+        }
         return true;
     }
 
@@ -259,11 +269,6 @@ bool ThreadsHandler::setData(const QModelIndex &idx, const QVariant &data, int r
     return false;
 }
 
-int ThreadsHandler::currentThreadIndex() const
-{
-    return rootItem()->indexOf(m_currentThread);
-}
-
 void ThreadsHandler::sort(int column, Qt::SortOrder order)
 {
     rootItem()->sortChildren([order, column](const ThreadItem *item1, const ThreadItem *item2) -> bool {

src/plugins/debugger/threadshandler.h

@@ -29,6 +29,7 @@
 
 #include <utils/treemodel.h>
 
+#include <QComboBox>
 #include <QPointer>
 
 ////////////////////////////////////////////////////////////////////////
@@ -77,7 +78,6 @@ class ThreadsHandler : public ThreadsHandlerModel
 public:
     explicit ThreadsHandler(DebuggerEngine *engine);
 
-    int currentThreadIndex() const;
     Thread currentThread() const;
     Thread threadForId(const QString &id) const;
     void setCurrentThread(const Thread &thread);
@@ -95,6 +95,8 @@ public:
     void notifyRunning(const QString &id);
     void notifyStopped(const QString &id);
 
+    QComboBox *threadSwitcher() { return m_comboBox; }
+
 private:
     void sort(int column, Qt::SortOrder order) override;
     QVariant data(const QModelIndex &index, int role) const override;
@@ -103,6 +105,7 @@ private:
     DebuggerEngine *m_engine;
     Thread m_currentThread;
     QHash<QString, QString> m_pidForGroupId;
+    QComboBox *m_comboBox;
 };
 
 } // namespace Internal