Move OverViewCombo to Utils::

Change-Id: I0724b6223ba9505effe151ce474f0f378671e60f
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/libs/utils/treeviewcombobox.cpp

@@ -0,0 +1,118 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "treeviewcombobox.h"
+
+#include <QWheelEvent>
+
+using namespace Utils;
+
+TreeViewComboBoxView::TreeViewComboBoxView(QWidget *parent)
+    : QTreeView(parent)
+{
+    // TODO: Disable the root for all items (with a custom delegate?)
+    setRootIsDecorated(false);
+}
+
+void TreeViewComboBoxView::adjustWidth(int width)
+{
+    setMaximumWidth(width);
+    setMinimumWidth(qMin(qMax(sizeHintForColumn(0), minimumSizeHint().width()), width));
+}
+
+
+TreeViewComboBox::TreeViewComboBox(QWidget *parent)
+    : QComboBox(parent), m_skipNextHide(false)
+{
+    m_view = new TreeViewComboBoxView;
+    m_view->setHeaderHidden(true);
+    m_view->setItemsExpandable(true);
+    setView(m_view);
+    m_view->viewport()->installEventFilter(this);
+}
+
+void TreeViewComboBox::wheelEvent(QWheelEvent *e)
+{
+    QModelIndex index = m_view->currentIndex();
+    if (e->delta() > 0) {
+        do
+            index = m_view->indexAbove(index);
+        while (index.isValid() && !(model()->flags(index) & Qt::ItemIsSelectable));
+    } else if (e->delta() < 0) {
+        do
+            index = m_view->indexBelow(index);
+        while (index.isValid() && !(model()->flags(index) & Qt::ItemIsSelectable));
+    }
+    e->accept();
+    if (!index.isValid())
+        return;
+
+    setCurrentIndex(index);
+
+    // for compatibility we emit activated with a useless row parameter
+    emit activated(index.row());
+}
+
+void TreeViewComboBox::setCurrentIndex(const QModelIndex &index)
+{
+    setRootModelIndex(model()->parent(index));
+    QComboBox::setCurrentIndex(index.row());
+    setRootModelIndex(QModelIndex());
+    m_view->setCurrentIndex(index);
+}
+
+bool TreeViewComboBox::eventFilter(QObject *object, QEvent *event)
+{
+    if (event->type() == QEvent::MouseButtonPress && object == view()->viewport()) {
+        QMouseEvent* mouseEvent = static_cast<QMouseEvent*>(event);
+        QModelIndex index = view()->indexAt(mouseEvent->pos());
+        if (!view()->visualRect(index).contains(mouseEvent->pos()))
+            m_skipNextHide = true;
+    }
+    return false;
+}
+
+void TreeViewComboBox::showPopup()
+{
+    m_view->adjustWidth(topLevelWidget()->geometry().width());
+    QComboBox::showPopup();
+}
+
+void TreeViewComboBox::hidePopup()
+{
+    if (m_skipNextHide)
+        m_skipNextHide = false;
+    else
+        QComboBox::hidePopup();
+}
+
+TreeViewComboBoxView *TreeViewComboBox::view() const
+{
+    return m_view;
+}