Implement go to previous split feature

These changes allows users to move between splits
using the hotkeys not only clockwise, but counterclockwise too

Change-Id: I2a30bc0cd869881c525674d7e40e622b4b3dc7f6
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/plugins/coreplugin/coreconstants.h

@@ -112,7 +112,8 @@ const char SPLIT_SIDE_BY_SIDE[]    = "QtCreator.SplitSideBySide";
 const char SPLIT_NEW_WINDOW[]      = "QtCreator.SplitNewWindow";
 const char REMOVE_CURRENT_SPLIT[]  = "QtCreator.RemoveCurrentSplit";
 const char REMOVE_ALL_SPLITS[]     = "QtCreator.RemoveAllSplits";
-const char GOTO_NEXT_SPLIT[]      = "QtCreator.GotoOtherSplit";
+const char GOTO_PREV_SPLIT[]       = "QtCreator.GoToPreviousSplit";
+const char GOTO_NEXT_SPLIT[]       = "QtCreator.GoToNextSplit";
 const char CLOSE[]                 = "QtCreator.Close";
 const char CLOSE_ALTERNATIVE[]     = "QtCreator.Close_Alternative"; // temporary, see QTCREATORBUG-72
 const char CLOSEALL[]              = "QtCreator.CloseAll";

src/plugins/coreplugin/editormanager/editormanager.cpp

@@ -412,6 +412,12 @@ void EditorManagerPrivate::init()
     mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
     connect(m_removeAllSplitsAction, SIGNAL(triggered()), this, SLOT(removeAllSplits()));
 
+    m_gotoPreviousSplitAction = new QAction(tr("Go to Previous Split or Window"), this);
+    cmd = ActionManager::registerAction(m_gotoPreviousSplitAction, Constants::GOTO_PREV_SPLIT, editManagerContext);
+    cmd->setDefaultKeySequence(QKeySequence(UseMacShortcuts ? tr("Meta+E,i") : tr("Ctrl+E,i")));
+    mwindow->addAction(cmd, Constants::G_WINDOW_SPLIT);
+    connect(m_gotoPreviousSplitAction, SIGNAL(triggered()), this, SLOT(gotoPreviousSplit()));
+
     m_gotoNextSplitAction = new QAction(tr("Go to Next Split or Window"), this);
     cmd = ActionManager::registerAction(m_gotoNextSplitAction, Constants::GOTO_NEXT_SPLIT, editManagerContext);
     cmd->setDefaultKeySequence(QKeySequence(UseMacShortcuts ? tr("Meta+E,o") : tr("Ctrl+E,o")));
@@ -1658,6 +1664,30 @@ void EditorManagerPrivate::gotoNextSplit()
         activateView(nextView);
 }
 
+void EditorManagerPrivate::gotoPreviousSplit()
+{
+    EditorView *view = currentEditorView();
+    if (!view)
+        return;
+    EditorView *prevView = view->findPreviousView();
+    if (!prevView) {
+        // we are in the "first" view in this editor area
+        int index = -1;
+        EditorArea *area = findEditorArea(view, &index);
+        QTC_ASSERT(area, return);
+        QTC_ASSERT(index >= 0 && index < d->m_editorAreas.size(), return);
+        // find previous editor area. this might be the same editor area if there's only one.
+        int nextIndex = index - 1;
+        if (nextIndex < 0)
+            nextIndex = d->m_editorAreas.count() - 1;
+        prevView = d->m_editorAreas.at(nextIndex)->findLastView();
+        QTC_CHECK(prevView);
+    }
+
+    if (prevView)
+        activateView(prevView);
+}
+
 void EditorManagerPrivate::makeCurrentEditorWritable()
 {
     if (IDocument* doc = EditorManager::currentDocument())

src/plugins/coreplugin/editormanager/editormanager_p.h

@@ -137,6 +137,7 @@ public slots:
 
     static void split(Qt::Orientation orientation);
     static void removeAllSplits();
+    static void gotoPreviousSplit();
     static void gotoNextSplit();
 
     void handleDocumentStateChange();
@@ -224,6 +225,7 @@ private:
     QAction *m_splitNewWindowAction;
     QAction *m_removeCurrentSplitAction;
     QAction *m_removeAllSplitsAction;
+    QAction *m_gotoPreviousSplitAction;
     QAction *m_gotoNextSplitAction;
 
     QAction *m_copyFilePathContextAction;

src/plugins/coreplugin/editormanager/editorview.cpp

@@ -184,6 +184,29 @@ EditorView *EditorView::findNextView()
     return 0;
 }
 
+EditorView *EditorView::findPreviousView()
+{
+    SplitterOrView *current = parentSplitterOrView();
+    QTC_ASSERT(current, return 0);
+    SplitterOrView *parent = current->findParentSplitter();
+    while (parent) {
+        QSplitter *splitter = parent->splitter();
+        QTC_ASSERT(splitter, return 0);
+        QTC_ASSERT(splitter->count() == 2, return 0);
+        // is current the last child? then the previous view is the first child in current's sibling
+        if (splitter->widget(1) == current) {
+            SplitterOrView *first = qobject_cast<SplitterOrView *>(splitter->widget(0));
+            QTC_ASSERT(first, return 0);
+            return first->findFirstView();
+        }
+        // otherwise go up the hierarchy
+        current = parent;
+        parent = current->findParentSplitter();
+    }
+    // current has no parent, so we are at the top and there is no "previous" view
+    return 0;
+}
+
 void EditorView::closeCurrentEditor()
 {
     IEditor *editor = currentEditor();
@@ -637,6 +660,19 @@ EditorView *SplitterOrView::findFirstView()
     return m_view;
 }
 
+EditorView *SplitterOrView::findLastView()
+{
+    if (m_splitter) {
+        for (int i = m_splitter->count() - 1; 0 < i; --i) {
+            if (SplitterOrView *splitterOrView = qobject_cast<SplitterOrView*>(m_splitter->widget(i)))
+                if (EditorView *result = splitterOrView->findLastView())
+                    return result;
+        }
+        return 0;
+    }
+    return m_view;
+}
+
 SplitterOrView *SplitterOrView::findParentSplitter() const
 {
     QWidget *w = parentWidget();

src/plugins/coreplugin/editormanager/editorview.h

@@ -85,6 +85,7 @@ public:
 
     SplitterOrView *parentSplitterOrView() const;
     EditorView *findNextView();
+    EditorView *findPreviousView();
 
     int editorCount() const;
     void addEditor(IEditor *editor);
@@ -197,6 +198,7 @@ public:
     void restoreState(const QByteArray &);
 
     EditorView *findFirstView();
+    EditorView *findLastView();
     SplitterOrView *findParentSplitter() const;
 
     QSize sizeHint() const { return minimumSizeHint(); }