demos/browser/modelmenu.cpp

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  41
  42 #include "modelmenu.h"
  43
  44 #include <QtCore/QAbstractItemModel>
  45 #include <qdebug.h>
  46
  47 ModelMenu::ModelMenu(QWidget * parent)
  48     : QMenu(parent)
  49     , m_maxRows(7)
  50     , m_firstSeparator(-1)
  51     , m_maxWidth(-1)
  52     , m_hoverRole(0)
  53     , m_separatorRole(0)
  54     , m_model(0)
  55 {
  56     connect(this, SIGNAL(aboutToShow()), this, SLOT(aboutToShow()));
  57 }
  58
  59 bool ModelMenu::prePopulated()
  60 {
  61     return false;
  62 }
  63
  64 void ModelMenu::postPopulated()
  65 {
  66 }
  67
  68 void ModelMenu::setModel(QAbstractItemModel *model)
  69 {
  70     m_model = model;
  71 }
  72
  73 QAbstractItemModel *ModelMenu::model() const
  74 {
  75     return m_model;
  76 }
  77
  78 void ModelMenu::setMaxRows(int max)
  79 {
  80     m_maxRows = max;
  81 }
  82
  83 int ModelMenu::maxRows() const
  84 {
  85     return m_maxRows;
  86 }
  87
  88 void ModelMenu::setFirstSeparator(int offset)
  89 {
  90     m_firstSeparator = offset;
  91 }
  92
  93 int ModelMenu::firstSeparator() const
  94 {
  95     return m_firstSeparator;
  96 }
  97
  98 void ModelMenu::setRootIndex(const QModelIndex &index)
  99 {
 100     m_root = index;
 101 }
 102
 103 QModelIndex ModelMenu::rootIndex() const
 104 {
 105     return m_root;
 106 }
 107
 108 void ModelMenu::setHoverRole(int role)
 109 {
 110     m_hoverRole = role;
 111 }
 112
 113 int ModelMenu::hoverRole() const
 114 {
 115     return m_hoverRole;
 116 }
 117
 118 void ModelMenu::setSeparatorRole(int role)
 119 {
 120     m_separatorRole = role;
 121 }
 122
 123 int ModelMenu::separatorRole() const
 124 {
 125     return m_separatorRole;
 126 }
 127
 128 Q_DECLARE_METATYPE(QModelIndex)
 129 void ModelMenu::aboutToShow()
 130 {
 131     if (QMenu *menu = qobject_cast<QMenu*>(sender())) {
 132         QVariant v = menu->menuAction()->data();
 133         if (v.canConvert<QModelIndex>()) {
 134             QModelIndex idx = qvariant_cast<QModelIndex>(v);
 135             createMenu(idx, -1, menu, menu);
 136             disconnect(menu, SIGNAL(aboutToShow()), this, SLOT(aboutToShow()));
 137             return;
 138         }
 139     }
 140
 141     clear();
 142     if (prePopulated())
 143         addSeparator();
 144     int max = m_maxRows;
 145     if (max != -1)
 146         max += m_firstSeparator;
 147     createMenu(m_root, max, this, this);
 148     postPopulated();
 149 }
 150
 151 void ModelMenu::createMenu(const QModelIndex &parent, int max, QMenu *parentMenu, QMenu *menu)
 152 {
 153     if (!menu) {
 154         QString title = parent.data().toString();
 155         menu = new QMenu(title, this);
 156         QIcon icon = qvariant_cast<QIcon>(parent.data(Qt::DecorationRole));
 157         menu->setIcon(icon);
 158         parentMenu->addMenu(menu);
 159         QVariant v;
 160         v.setValue(parent);
 161         menu->menuAction()->setData(v);
 162         connect(menu, SIGNAL(aboutToShow()), this, SLOT(aboutToShow()));
 163         return;
 164     }
 165
 166     int end = m_model->rowCount(parent);
 167     if (max != -1)
 168         end = qMin(max, end);
 169
 170     connect(menu, SIGNAL(triggered(QAction*)), this, SLOT(triggered(QAction*)));
 171     connect(menu, SIGNAL(hovered(QAction*)), this, SLOT(hovered(QAction*)));
 172
 173     for (int i = 0; i < end; ++i) {
 174         QModelIndex idx = m_model->index(i, 0, parent);
 175         if (m_model->hasChildren(idx)) {
 176             createMenu(idx, -1, menu);
 177         } else {
 178             if (m_separatorRole != 0
 179                 && idx.data(m_separatorRole).toBool())
 180                 addSeparator();
 181             else
 182                 menu->addAction(makeAction(idx));
 183         }
 184         if (menu == this && i == m_firstSeparator - 1)
 185             addSeparator();
 186     }
 187 }
 188
 189 QAction *ModelMenu::makeAction(const QModelIndex &index)
 190 {
 191     QIcon icon = qvariant_cast<QIcon>(index.data(Qt::DecorationRole));
 192     QAction *action = makeAction(icon, index.data().toString(), this);
 193     QVariant v;
 194     v.setValue(index);
 195     action->setData(v);
 196     return action;
 197 }
 198
 199 QAction *ModelMenu::makeAction(const QIcon &icon, const QString &text, QObject *parent)
 200 {
 201     QFontMetrics fm(font());
 202     if (-1 == m_maxWidth)
 203         m_maxWidth = fm.width(QLatin1Char('m')) * 30;
 204     QString smallText = fm.elidedText(text, Qt::ElideMiddle, m_maxWidth);
 205     return new QAction(icon, smallText, parent);
 206 }
 207
 208 void ModelMenu::triggered(QAction *action)
 209 {
 210     QVariant v = action->data();
 211     if (v.canConvert<QModelIndex>()) {
 212         QModelIndex idx = qvariant_cast<QModelIndex>(v);
 213         emit activated(idx);
 214     }
 215 }
 216
 217 void ModelMenu::hovered(QAction *action)
 218 {
 219     QVariant v = action->data();
 220     if (v.canConvert<QModelIndex>()) {
 221         QModelIndex idx = qvariant_cast<QModelIndex>(v);
 222         QString hoveredString = idx.data(m_hoverRole).toString();
 223         if (!hoveredString.isEmpty())
 224             emit hovered(hoveredString);
 225     }
 226 }
 227