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