src/kitemviews/kfileitemlistview.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  18  ***************************************************************************/
  19
  20 #include "kfileitemlistview.h"
  21
  22 #include "kitemlistgroupheader.h"
  23 #include "kfileitemmodelrolesupdater.h"
  24 #include "kfileitemlistwidget.h"
  25 #include "kfileitemmodel.h"
  26 #include <KLocale>
  27 #include <KStringHandler>
  28
  29 #include <KDebug>
  30 #include <KIcon>
  31
  32 #include <QTextLine>
  33 #include <QTimer>
  34
  35 #define KFILEITEMLISTVIEW_DEBUG
  36
  37 namespace {
  38     const int ShortInterval = 50;
  39     const int LongInterval = 300;
  40 }
  41
  42 KFileItemListView::KFileItemListView(QGraphicsWidget* parent) :
  43     KItemListView(parent),
  44     m_itemLayout(IconsLayout),
  45     m_modelRolesUpdater(0),
  46     m_updateVisibleIndexRangeTimer(0),
  47     m_updateIconSizeTimer(0),
  48     m_minimumRolesWidths()
  49 {
  50     setAcceptDrops(true);
  51
  52     setScrollOrientation(Qt::Vertical);
  53     setWidgetCreator(new KItemListWidgetCreator<KFileItemListWidget>());
  54     setGroupHeaderCreator(new KItemListGroupHeaderCreator<KItemListGroupHeader>());
  55
  56     m_updateVisibleIndexRangeTimer = new QTimer(this);
  57     m_updateVisibleIndexRangeTimer->setSingleShot(true);
  58     m_updateVisibleIndexRangeTimer->setInterval(ShortInterval);
  59     connect(m_updateVisibleIndexRangeTimer, SIGNAL(timeout()), this, SLOT(updateVisibleIndexRange()));
  60
  61     m_updateIconSizeTimer = new QTimer(this);
  62     m_updateIconSizeTimer->setSingleShot(true);
  63     m_updateIconSizeTimer->setInterval(ShortInterval);
  64     connect(m_updateIconSizeTimer, SIGNAL(timeout()), this, SLOT(updateIconSize()));
  65
  66     updateMinimumRolesWidths();
  67 }
  68
  69 KFileItemListView::~KFileItemListView()
  70 {
  71     delete widgetCreator();
  72     delete groupHeaderCreator();
  73
  74     delete m_modelRolesUpdater;
  75     m_modelRolesUpdater = 0;
  76 }
  77
  78 void KFileItemListView::setPreviewsShown(bool show)
  79 {
  80     if (m_modelRolesUpdater) {
  81         m_modelRolesUpdater->setPreviewShown(show);
  82     }
  83 }
  84
  85 bool KFileItemListView::previewsShown() const
  86 {
  87     return m_modelRolesUpdater->isPreviewShown();
  88 }
  89
  90 void KFileItemListView::setItemLayout(Layout layout)
  91 {
  92     if (m_itemLayout != layout) {
  93         m_itemLayout = layout;
  94         updateLayoutOfVisibleItems();
  95     }
  96 }
  97
  98 KFileItemListView::Layout KFileItemListView::itemLayout() const
  99 {
 100     return m_itemLayout;
 101 }
 102
 103 QSizeF KFileItemListView::itemSizeHint(int index) const
 104 {
 105     const QHash<QByteArray, QVariant> values = model()->data(index);
 106     const KItemListStyleOption& option = styleOption();
 107     const int additionalRolesCount = qMax(visibleRoles().count() - 1, 0);
 108
 109     switch (m_itemLayout) {
 110     case IconsLayout: {
 111         const QString text = KStringHandler::preProcessWrap(values["name"].toString());
 112
 113         const qreal maxWidth = itemSize().width() - 2 * option.margin;
 114         int textLinesCount = 0;
 115         QTextLine line;
 116
 117         // Calculate the number of lines required for wrapping the name
 118         QTextOption textOption(Qt::AlignHCenter);
 119         textOption.setWrapMode(QTextOption::WrapAtWordBoundaryOrAnywhere);
 120
 121         QTextLayout layout(text, option.font);
 122         layout.setTextOption(textOption);
 123         layout.beginLayout();
 124         while ((line = layout.createLine()).isValid()) {
 125             line.setLineWidth(maxWidth);
 126             line.naturalTextWidth();
 127             ++textLinesCount;
 128         }
 129         layout.endLayout();
 130
 131         // Add one line for each additional information
 132         textLinesCount += additionalRolesCount;
 133
 134         const qreal height = textLinesCount * option.fontMetrics.height() +
 135                              option.iconSize +
 136                              option.margin * 4;
 137         return QSizeF(itemSize().width(), height);
 138     }
 139
 140     case CompactLayout: {
 141         // For each row exactly one role is shown. Calculate the maximum required width that is necessary
 142         // to show all roles without horizontal clipping.
 143         qreal maximumRequiredWidth = 0.0;
 144         QHashIterator<QByteArray, int> it(visibleRoles());
 145         while (it.hasNext()) {
 146             it.next();
 147             const QByteArray& role = it.key();
 148             const QString text = values[role].toString();
 149             const qreal requiredWidth = option.fontMetrics.width(text);
 150             maximumRequiredWidth = qMax(maximumRequiredWidth, requiredWidth);
 151         }
 152
 153         const qreal width = option.margin * 4 + option.iconSize + maximumRequiredWidth;
 154         const qreal height = option.margin * 2 + qMax(option.iconSize, (1 + additionalRolesCount) * option.fontMetrics.height());
 155         return QSizeF(width, height);
 156     }
 157
 158     case DetailsLayout: {
 159         // The width will be determined dynamically by KFileItemListView::visibleRoleSizes()
 160         const qreal height = option.margin * 2 + qMax(option.iconSize, option.fontMetrics.height());
 161         return QSizeF(-1, height);
 162     }
 163
 164     default:
 165         Q_ASSERT(false);
 166         break;
 167     }
 168
 169     return QSize();
 170 }
 171
 172 QHash<QByteArray, QSizeF> KFileItemListView::visibleRoleSizes() const
 173 {
 174     QElapsedTimer timer;
 175     timer.start();
 176
 177     QHash<QByteArray, QSizeF> sizes;
 178
 179     const int itemCount = model()->count();
 180     for (int i = 0; i < itemCount; ++i) {
 181         QHashIterator<QByteArray, int> it(visibleRoles());
 182         while (it.hasNext()) {
 183             it.next();
 184             const QByteArray& visibleRole = it.key();
 185
 186             QSizeF maxSize = sizes.value(visibleRole, QSizeF(0, 0));
 187
 188             const QSizeF itemSize = visibleRoleSizeHint(i, visibleRole);
 189             maxSize = maxSize.expandedTo(itemSize);
 190             sizes.insert(visibleRole, maxSize);
 191         }
 192
 193         if (i > 100 && timer.elapsed() > 200) {
 194             // When having several thousands of items calculating the sizes can get
 195             // very expensive. We accept a possibly too small role-size in favour
 196             // of having no blocking user interface.
 197             #ifdef KFILEITEMLISTVIEW_DEBUG
 198                 kDebug() << "Timer exceeded, stopped after" << i << "items";
 199             #endif
 200             break;
 201         }
 202     }
 203
 204 #ifdef KFILEITEMLISTVIEW_DEBUG
 205     kDebug() << "[TIME] Calculated dynamic item size for " << itemCount << "items:" << timer.elapsed();
 206 #endif
 207     return sizes;
 208 }
 209
 210 QPixmap KFileItemListView::createDragPixmap(const QSet<int>& indexes) const
 211 {
 212     QPixmap pixmap;
 213
 214     if (model()) {
 215         QSetIterator<int> it(indexes);
 216         while (it.hasNext()) {
 217             const int index = it.next();
 218             // TODO: Only one item is considered currently
 219             pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 220             if (pixmap.isNull()) {
 221                 KIcon icon(model()->data(index).value("iconName").toString());
 222                 pixmap = icon.pixmap(itemSize().toSize());
 223             }
 224         }
 225     }
 226
 227     return pixmap;
 228 }
 229
 230 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 231 {
 232     KFileItemListWidget* fileItemListWidget = static_cast<KFileItemListWidget*>(item);
 233
 234     switch (m_itemLayout) {
 235     case IconsLayout:   fileItemListWidget->setLayout(KFileItemListWidget::IconsLayout); break;
 236     case CompactLayout: fileItemListWidget->setLayout(KFileItemListWidget::CompactLayout); break;
 237     case DetailsLayout: fileItemListWidget->setLayout(KFileItemListWidget::DetailsLayout); break;
 238     default:            Q_ASSERT(false); break;
 239     }
 240 }
 241
 242 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 243 {
 244     Q_UNUSED(previous);
 245     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 246
 247     if (m_modelRolesUpdater) {
 248         delete m_modelRolesUpdater;
 249     }
 250
 251     m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 252     const int size = styleOption().iconSize;
 253     m_modelRolesUpdater->setIconSize(QSize(size, size));
 254 }
 255
 256 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 257 {
 258     Q_UNUSED(current);
 259     Q_UNUSED(previous);
 260     updateLayoutOfVisibleItems();
 261 }
 262
 263 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 264 {
 265     Q_UNUSED(current);
 266     Q_UNUSED(previous);
 267     triggerVisibleIndexRangeUpdate();
 268 }
 269
 270 void KFileItemListView::onOffsetChanged(qreal current, qreal previous)
 271 {
 272     Q_UNUSED(current);
 273     Q_UNUSED(previous);
 274     triggerVisibleIndexRangeUpdate();
 275 }
 276
 277 void KFileItemListView::onVisibleRolesChanged(const QHash<QByteArray, int>& current, const QHash<QByteArray, int>& previous)
 278 {
 279     Q_UNUSED(previous);
 280
 281     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 282     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 283
 284     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 285     // Add all roles that are mandatory for having a working KFileItemListView:
 286     QSet<QByteArray> keys = current.keys().toSet();
 287     QSet<QByteArray> roles = keys;
 288     roles.insert("iconPixmap");
 289     roles.insert("iconName");
 290     roles.insert("name"); // TODO: just don't allow to disable it
 291     roles.insert("isDir");
 292     if (m_itemLayout == DetailsLayout) {
 293         roles.insert("isExpanded");
 294         roles.insert("expansionLevel");
 295     }
 296
 297     fileItemModel->setRoles(roles);
 298
 299     m_modelRolesUpdater->setRoles(keys);
 300 }
 301
 302 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 303 {
 304     Q_UNUSED(current);
 305     Q_UNUSED(previous);
 306     triggerIconSizeUpdate();
 307 }
 308
 309 void KFileItemListView::onTransactionBegin()
 310 {
 311     m_modelRolesUpdater->setPaused(true);
 312 }
 313
 314 void KFileItemListView::onTransactionEnd()
 315 {
 316     // Only unpause the model-roles-updater if no timer is active. If one
 317     // timer is still active the model-roles-updater will be unpaused later as
 318     // soon as the timer has been exceeded.
 319     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 320                              m_updateIconSizeTimer->isActive();
 321     if (!timerActive) {
 322         m_modelRolesUpdater->setPaused(false);
 323     }
 324 }
 325
 326 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 327 {
 328     KItemListView::resizeEvent(event);
 329     triggerVisibleIndexRangeUpdate();
 330 }
 331
 332 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 333 {
 334     KItemListView::slotItemsRemoved(itemRanges);
 335     updateTimersInterval();
 336 }
 337
 338 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 339 {
 340     m_modelRolesUpdater->setPaused(true);
 341     m_updateVisibleIndexRangeTimer->start();
 342 }
 343
 344 void KFileItemListView::updateVisibleIndexRange()
 345 {
 346     if (!m_modelRolesUpdater) {
 347         return;
 348     }
 349
 350     const int index = firstVisibleIndex();
 351     const int count = lastVisibleIndex() - index + 1;
 352     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 353
 354     if (m_updateIconSizeTimer->isActive()) {
 355         // If the icon-size update is pending do an immediate update
 356         // of the icon-size before unpausing m_modelRolesUpdater. This prevents
 357         // an unnecessary expensive recreation of all previews afterwards.
 358         m_updateIconSizeTimer->stop();
 359         const KItemListStyleOption& option = styleOption();
 360         m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 361     }
 362
 363     m_modelRolesUpdater->setPaused(isTransactionActive());
 364     updateTimersInterval();
 365 }
 366
 367 void KFileItemListView::triggerIconSizeUpdate()
 368 {
 369     m_modelRolesUpdater->setPaused(true);
 370     m_updateIconSizeTimer->start();
 371 }
 372
 373 void KFileItemListView::updateIconSize()
 374 {
 375     if (!m_modelRolesUpdater) {
 376         return;
 377     }
 378
 379     const KItemListStyleOption& option = styleOption();
 380     m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 381
 382     if (m_updateVisibleIndexRangeTimer->isActive()) {
 383         // If the visibility-index-range update is pending do an immediate update
 384         // of the range before unpausing m_modelRolesUpdater. This prevents
 385         // an unnecessary expensive recreation of all previews afterwards.
 386         m_updateVisibleIndexRangeTimer->stop();
 387         const int index = firstVisibleIndex();
 388         const int count = lastVisibleIndex() - index + 1;
 389         m_modelRolesUpdater->setVisibleIndexRange(index, count);
 390     }
 391
 392     m_modelRolesUpdater->setPaused(isTransactionActive());
 393     updateTimersInterval();
 394 }
 395
 396 QSizeF KFileItemListView::visibleRoleSizeHint(int index, const QByteArray& role) const
 397 {
 398     const KItemListStyleOption& option = styleOption();
 399
 400     qreal width = m_minimumRolesWidths.value(role, 0);
 401     const qreal height = option.margin * 2 + option.fontMetrics.height();
 402
 403     const QVariant value = model()->data(index).value(role);
 404     const QString text = value.toString();
 405     if (!text.isEmpty()) {
 406         width = qMax(width, qreal(option.margin * 2 + option.fontMetrics.width(text)));
 407     }
 408
 409     return QSizeF(width, height);
 410 }
 411
 412 void KFileItemListView::updateLayoutOfVisibleItems()
 413 {
 414     foreach (KItemListWidget* widget, visibleItemListWidgets()) {
 415         initializeItemListWidget(widget);
 416     }
 417     triggerVisibleIndexRangeUpdate();
 418 }
 419
 420 void KFileItemListView::updateTimersInterval()
 421 {
 422     if (!model()) {
 423         return;
 424     }
 425
 426     // The ShortInterval is used for cases like switching the directory: If the
 427     // model is empty and filled later the creation of the previews should be done
 428     // as soon as possible. The LongInterval is used when the model already contains
 429     // items and assures that operations like zooming don't result in too many temporary
 430     // recreations of the previews.
 431
 432     const int interval = (model()->count() <= 0) ? ShortInterval : LongInterval;
 433     m_updateVisibleIndexRangeTimer->setInterval(interval);
 434     m_updateIconSizeTimer->setInterval(interval);
 435 }
 436
 437 void KFileItemListView::updateMinimumRolesWidths()
 438 {
 439     m_minimumRolesWidths.clear();
 440
 441     const KItemListStyleOption& option = styleOption();
 442     const QString sizeText = QLatin1String("888888") + i18nc("@item:intable", "items");
 443     m_minimumRolesWidths.insert("size", option.fontMetrics.width(sizeText));
 444 }
 445
 446 #include "kfileitemlistview.moc"