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     // The group headers are children of the widgets created by
  72     // widgetCreator(). So it is mandatory to delete the group headers
  73     // first.
  74     delete groupHeaderCreator();
  75     delete widgetCreator();
  76
  77     delete m_modelRolesUpdater;
  78     m_modelRolesUpdater = 0;
  79 }
  80
  81 void KFileItemListView::setPreviewsShown(bool show)
  82 {
  83     if (m_modelRolesUpdater) {
  84         m_modelRolesUpdater->setPreviewShown(show);
  85     }
  86 }
  87
  88 bool KFileItemListView::previewsShown() const
  89 {
  90     return m_modelRolesUpdater->isPreviewShown();
  91 }
  92
  93 void KFileItemListView::setItemLayout(Layout layout)
  94 {
  95     if (m_itemLayout != layout) {
  96         m_itemLayout = layout;
  97         updateLayoutOfVisibleItems();
  98     }
  99 }
 100
 101 KFileItemListView::Layout KFileItemListView::itemLayout() const
 102 {
 103     return m_itemLayout;
 104 }
 105
 106 QSizeF KFileItemListView::itemSizeHint(int index) const
 107 {
 108     const QHash<QByteArray, QVariant> values = model()->data(index);
 109     const KItemListStyleOption& option = styleOption();
 110     const int additionalRolesCount = qMax(visibleRoles().count() - 1, 0);
 111
 112     switch (m_itemLayout) {
 113     case IconsLayout: {
 114         const QString text = KStringHandler::preProcessWrap(values["name"].toString());
 115
 116         const qreal maxWidth = itemSize().width() - 2 * option.margin;
 117         int textLinesCount = 0;
 118         QTextLine line;
 119
 120         // Calculate the number of lines required for wrapping the name
 121         QTextOption textOption(Qt::AlignHCenter);
 122         textOption.setWrapMode(QTextOption::WrapAtWordBoundaryOrAnywhere);
 123
 124         QTextLayout layout(text, option.font);
 125         layout.setTextOption(textOption);
 126         layout.beginLayout();
 127         while ((line = layout.createLine()).isValid()) {
 128             line.setLineWidth(maxWidth);
 129             line.naturalTextWidth();
 130             ++textLinesCount;
 131         }
 132         layout.endLayout();
 133
 134         // Add one line for each additional information
 135         textLinesCount += additionalRolesCount;
 136
 137         const qreal height = textLinesCount * option.fontMetrics.height() +
 138                              option.iconSize +
 139                              option.margin * 4;
 140         return QSizeF(itemSize().width(), height);
 141     }
 142
 143     case CompactLayout: {
 144         // For each row exactly one role is shown. Calculate the maximum required width that is necessary
 145         // to show all roles without horizontal clipping.
 146         qreal maximumRequiredWidth = 0.0;
 147
 148         foreach (const QByteArray& role, visibleRoles()) {
 149             const QString text = KFileItemListWidget::roleText(role, values);
 150             const qreal requiredWidth = option.fontMetrics.width(text);
 151             maximumRequiredWidth = qMax(maximumRequiredWidth, requiredWidth);
 152         }
 153
 154         const qreal width = option.margin * 4 + option.iconSize + maximumRequiredWidth;
 155         const qreal height = option.margin * 2 + qMax(option.iconSize, (1 + additionalRolesCount) * option.fontMetrics.height());
 156         return QSizeF(width, height);
 157     }
 158
 159     case DetailsLayout: {
 160         // The width will be determined dynamically by KFileItemListView::visibleRoleSizes()
 161         const qreal height = option.margin * 2 + qMax(option.iconSize, option.fontMetrics.height());
 162         return QSizeF(-1, height);
 163     }
 164
 165     default:
 166         Q_ASSERT(false);
 167         break;
 168     }
 169
 170     return QSize();
 171 }
 172
 173 QHash<QByteArray, QSizeF> KFileItemListView::visibleRolesSizes(const KItemRangeList& itemRanges) const
 174 {
 175     QElapsedTimer timer;
 176     timer.start();
 177
 178     QHash<QByteArray, QSizeF> sizes;
 179
 180     int calculatedItemCount = 0;
 181     bool maxTimeExceeded = false;
 182     foreach (const KItemRange& itemRange, itemRanges) {
 183         const int startIndex = itemRange.index;
 184         const int endIndex = startIndex + itemRange.count - 1;
 185
 186         for (int i = startIndex; i <= endIndex; ++i) {
 187             foreach (const QByteArray& visibleRole, visibleRoles()) {
 188                 QSizeF maxSize = sizes.value(visibleRole, QSizeF(0, 0));
 189                 const QSizeF itemSize = visibleRoleSizeHint(i, visibleRole);
 190                 maxSize = maxSize.expandedTo(itemSize);
 191                 sizes.insert(visibleRole, maxSize);
 192             }
 193
 194             if (calculatedItemCount > 100 && timer.elapsed() > 200) {
 195                 // When having several thousands of items calculating the sizes can get
 196                 // very expensive. We accept a possibly too small role-size in favour
 197                 // of having no blocking user interface.
 198                 #ifdef KFILEITEMLISTVIEW_DEBUG
 199                     kDebug() << "Timer exceeded, stopped after" << calculatedItemCount << "items";
 200                 #endif
 201                 maxTimeExceeded = true;
 202                 break;
 203             }
 204             ++calculatedItemCount;
 205         }
 206         if (maxTimeExceeded) {
 207             break;
 208         }
 209     }
 210
 211 #ifdef KFILEITEMLISTVIEW_DEBUG
 212     int rangesItemCount = 0;
 213     foreach (const KItemRange& itemRange, itemRanges) {
 214         rangesItemCount += itemRange.count;
 215     }
 216     kDebug() << "[TIME] Calculated dynamic item size for " << rangesItemCount << "items:" << timer.elapsed();
 217 #endif
 218     return sizes;
 219 }
 220
 221 QPixmap KFileItemListView::createDragPixmap(const QSet<int>& indexes) const
 222 {
 223     QPixmap pixmap;
 224
 225     if (model()) {
 226         QSetIterator<int> it(indexes);
 227         while (it.hasNext()) {
 228             const int index = it.next();
 229             // TODO: Only one item is considered currently
 230             pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 231             if (pixmap.isNull()) {
 232                 KIcon icon(model()->data(index).value("iconName").toString());
 233                 pixmap = icon.pixmap(itemSize().toSize());
 234             }
 235         }
 236     }
 237
 238     return pixmap;
 239 }
 240
 241 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 242 {
 243     KFileItemListWidget* fileItemListWidget = static_cast<KFileItemListWidget*>(item);
 244
 245     switch (m_itemLayout) {
 246     case IconsLayout:   fileItemListWidget->setLayout(KFileItemListWidget::IconsLayout); break;
 247     case CompactLayout: fileItemListWidget->setLayout(KFileItemListWidget::CompactLayout); break;
 248     case DetailsLayout: fileItemListWidget->setLayout(KFileItemListWidget::DetailsLayout); break;
 249     default:            Q_ASSERT(false); break;
 250     }
 251
 252     fileItemListWidget->setAlternatingBackgroundColors(m_itemLayout == DetailsLayout);
 253 }
 254
 255 bool KFileItemListView::itemSizeHintUpdateRequired(const QSet<QByteArray>& changedRoles) const
 256 {
 257     // Even if the icons have a different size they are always aligned within
 258     // the area defined by KItemStyleOption.iconSize and hence result in no
 259     // change of the item-size.
 260     const bool containsIconName = changedRoles.contains("iconName");
 261     const bool containsIconPixmap = changedRoles.contains("iconPixmap");
 262     const int count = changedRoles.count();
 263
 264     const bool iconChanged = (containsIconName && containsIconPixmap && count == 2) ||
 265                              (containsIconName && count == 1) ||
 266                              (containsIconPixmap && count == 1);
 267     return !iconChanged;
 268 }
 269
 270 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 271 {
 272     Q_UNUSED(previous);
 273     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 274
 275     if (m_modelRolesUpdater) {
 276         delete m_modelRolesUpdater;
 277     }
 278
 279     m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 280     const int size = styleOption().iconSize;
 281     m_modelRolesUpdater->setIconSize(QSize(size, size));
 282 }
 283
 284 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 285 {
 286     Q_UNUSED(current);
 287     Q_UNUSED(previous);
 288     updateLayoutOfVisibleItems();
 289 }
 290
 291 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 292 {
 293     Q_UNUSED(current);
 294     Q_UNUSED(previous);
 295     triggerVisibleIndexRangeUpdate();
 296 }
 297
 298 void KFileItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 299 {
 300     Q_UNUSED(current);
 301     Q_UNUSED(previous);
 302     triggerVisibleIndexRangeUpdate();
 303 }
 304
 305 void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 306 {
 307     Q_UNUSED(previous);
 308
 309     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 310     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 311
 312     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 313     // Add all roles that are mandatory for having a working KFileItemListView:
 314     QSet<QByteArray> keys = current.toSet();
 315     QSet<QByteArray> roles = keys;
 316     roles.insert("iconPixmap");
 317     roles.insert("iconName");
 318     roles.insert("name"); // TODO: just don't allow to disable it
 319     roles.insert("isDir");
 320     if (m_itemLayout == DetailsLayout) {
 321         roles.insert("isExpanded");
 322         roles.insert("expansionLevel");
 323     }
 324
 325     fileItemModel->setRoles(roles);
 326
 327     m_modelRolesUpdater->setRoles(keys);
 328 }
 329
 330 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 331 {
 332     Q_UNUSED(current);
 333     Q_UNUSED(previous);
 334     triggerIconSizeUpdate();
 335 }
 336
 337 void KFileItemListView::onTransactionBegin()
 338 {
 339     m_modelRolesUpdater->setPaused(true);
 340 }
 341
 342 void KFileItemListView::onTransactionEnd()
 343 {
 344     // Only unpause the model-roles-updater if no timer is active. If one
 345     // timer is still active the model-roles-updater will be unpaused later as
 346     // soon as the timer has been exceeded.
 347     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 348                              m_updateIconSizeTimer->isActive();
 349     if (!timerActive) {
 350         m_modelRolesUpdater->setPaused(false);
 351     }
 352 }
 353
 354 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 355 {
 356     KItemListView::resizeEvent(event);
 357     triggerVisibleIndexRangeUpdate();
 358 }
 359
 360 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 361 {
 362     KItemListView::slotItemsRemoved(itemRanges);
 363     updateTimersInterval();
 364 }
 365
 366 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 367 {
 368     m_modelRolesUpdater->setPaused(true);
 369     m_updateVisibleIndexRangeTimer->start();
 370 }
 371
 372 void KFileItemListView::updateVisibleIndexRange()
 373 {
 374     if (!m_modelRolesUpdater) {
 375         return;
 376     }
 377
 378     const int index = firstVisibleIndex();
 379     const int count = lastVisibleIndex() - index + 1;
 380     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 381
 382     if (m_updateIconSizeTimer->isActive()) {
 383         // If the icon-size update is pending do an immediate update
 384         // of the icon-size before unpausing m_modelRolesUpdater. This prevents
 385         // an unnecessary expensive recreation of all previews afterwards.
 386         m_updateIconSizeTimer->stop();
 387         const KItemListStyleOption& option = styleOption();
 388         m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 389     }
 390
 391     m_modelRolesUpdater->setPaused(isTransactionActive());
 392     updateTimersInterval();
 393 }
 394
 395 void KFileItemListView::triggerIconSizeUpdate()
 396 {
 397     m_modelRolesUpdater->setPaused(true);
 398     m_updateIconSizeTimer->start();
 399 }
 400
 401 void KFileItemListView::updateIconSize()
 402 {
 403     if (!m_modelRolesUpdater) {
 404         return;
 405     }
 406
 407     const KItemListStyleOption& option = styleOption();
 408     m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 409
 410     if (m_updateVisibleIndexRangeTimer->isActive()) {
 411         // If the visibility-index-range update is pending do an immediate update
 412         // of the range before unpausing m_modelRolesUpdater. This prevents
 413         // an unnecessary expensive recreation of all previews afterwards.
 414         m_updateVisibleIndexRangeTimer->stop();
 415         const int index = firstVisibleIndex();
 416         const int count = lastVisibleIndex() - index + 1;
 417         m_modelRolesUpdater->setVisibleIndexRange(index, count);
 418     }
 419
 420     m_modelRolesUpdater->setPaused(isTransactionActive());
 421     updateTimersInterval();
 422 }
 423
 424 QSizeF KFileItemListView::visibleRoleSizeHint(int index, const QByteArray& role) const
 425 {
 426     const KItemListStyleOption& option = styleOption();
 427
 428     qreal width = m_minimumRolesWidths.value(role, 0);
 429     const qreal height = option.margin * 2 + option.fontMetrics.height();
 430
 431     const QHash<QByteArray, QVariant> values = model()->data(index);
 432     const QString text = KFileItemListWidget::roleText(role, values);
 433     if (!text.isEmpty()) {
 434         const qreal columnMargin = option.margin * 3;
 435         width = qMax(width, qreal(2 * columnMargin + option.fontMetrics.width(text)));
 436     }
 437
 438     if (role == "name") {
 439         // Increase the width by the expansion-toggle and the current expansion level
 440         const int expansionLevel = values.value("expansionLevel", 0).toInt();
 441         width += option.margin + expansionLevel * itemSize().height() + KIconLoader::SizeSmall;
 442
 443         // Increase the width by the required space for the icon
 444         width += option.margin * 2 + option.iconSize;
 445     }
 446
 447     return QSizeF(width, height);
 448 }
 449
 450 void KFileItemListView::updateLayoutOfVisibleItems()
 451 {
 452     foreach (KItemListWidget* widget, visibleItemListWidgets()) {
 453         initializeItemListWidget(widget);
 454     }
 455     triggerVisibleIndexRangeUpdate();
 456 }
 457
 458 void KFileItemListView::updateTimersInterval()
 459 {
 460     if (!model()) {
 461         return;
 462     }
 463
 464     // The ShortInterval is used for cases like switching the directory: If the
 465     // model is empty and filled later the creation of the previews should be done
 466     // as soon as possible. The LongInterval is used when the model already contains
 467     // items and assures that operations like zooming don't result in too many temporary
 468     // recreations of the previews.
 469
 470     const int interval = (model()->count() <= 0) ? ShortInterval : LongInterval;
 471     m_updateVisibleIndexRangeTimer->setInterval(interval);
 472     m_updateIconSizeTimer->setInterval(interval);
 473 }
 474
 475 void KFileItemListView::updateMinimumRolesWidths()
 476 {
 477     m_minimumRolesWidths.clear();
 478
 479     const KItemListStyleOption& option = styleOption();
 480     const QString sizeText = QLatin1String("888888") + i18nc("@item:intable", "items");
 481     m_minimumRolesWidths.insert("size", option.fontMetrics.width(sizeText));
 482 }
 483
 484 #include "kfileitemlistview.moc"