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 "kfileitemlistgroupheader.h"
  23 #include "kfileitemmodelrolesupdater.h"
  24 #include "kfileitemlistwidget.h"
  25 #include "kfileitemmodel.h"
  26 #include "kpixmapmodifier_p.h"
  27 #include <KLocale>
  28 #include <KStringHandler>
  29
  30 #include <KDebug>
  31 #include <KIcon>
  32
  33 #include <QPainter>
  34 #include <QTextLine>
  35 #include <QTimer>
  36
  37 #define KFILEITEMLISTVIEW_DEBUG
  38
  39 namespace {
  40     const int ShortInterval = 50;
  41     const int LongInterval = 300;
  42 }
  43
  44 KFileItemListView::KFileItemListView(QGraphicsWidget* parent) :
  45     KItemListView(parent),
  46     m_itemLayout(IconsLayout),
  47     m_modelRolesUpdater(0),
  48     m_updateVisibleIndexRangeTimer(0),
  49     m_updateIconSizeTimer(0),
  50     m_minimumRolesWidths()
  51 {
  52     setAcceptDrops(true);
  53
  54     setScrollOrientation(Qt::Vertical);
  55     setWidgetCreator(new KItemListWidgetCreator<KFileItemListWidget>());
  56     setGroupHeaderCreator(new KItemListGroupHeaderCreator<KFileItemListGroupHeader>());
  57
  58     m_updateVisibleIndexRangeTimer = new QTimer(this);
  59     m_updateVisibleIndexRangeTimer->setSingleShot(true);
  60     m_updateVisibleIndexRangeTimer->setInterval(ShortInterval);
  61     connect(m_updateVisibleIndexRangeTimer, SIGNAL(timeout()), this, SLOT(updateVisibleIndexRange()));
  62
  63     m_updateIconSizeTimer = new QTimer(this);
  64     m_updateIconSizeTimer->setSingleShot(true);
  65     m_updateIconSizeTimer->setInterval(ShortInterval);
  66     connect(m_updateIconSizeTimer, SIGNAL(timeout()), this, SLOT(updateIconSize()));
  67
  68     setVisibleRoles(QList<QByteArray>() << "name");
  69
  70     updateMinimumRolesWidths();
  71 }
  72
  73 KFileItemListView::~KFileItemListView()
  74 {
  75     // The group headers are children of the widgets created by
  76     // widgetCreator(). So it is mandatory to delete the group headers
  77     // first.
  78     delete groupHeaderCreator();
  79     delete widgetCreator();
  80
  81     delete m_modelRolesUpdater;
  82     m_modelRolesUpdater = 0;
  83 }
  84
  85 void KFileItemListView::setPreviewsShown(bool show)
  86 {
  87     if (m_modelRolesUpdater) {
  88         m_modelRolesUpdater->setPreviewShown(show);
  89     }
  90 }
  91
  92 bool KFileItemListView::previewsShown() const
  93 {
  94     return m_modelRolesUpdater->isPreviewShown();
  95 }
  96
  97 void KFileItemListView::setItemLayout(Layout layout)
  98 {
  99     if (m_itemLayout != layout) {
 100         m_itemLayout = layout;
 101         updateLayoutOfVisibleItems();
 102     }
 103 }
 104
 105 KFileItemListView::Layout KFileItemListView::itemLayout() const
 106 {
 107     return m_itemLayout;
 108 }
 109
 110 QSizeF KFileItemListView::itemSizeHint(int index) const
 111 {
 112     const QHash<QByteArray, QVariant> values = model()->data(index);
 113     const KItemListStyleOption& option = styleOption();
 114     const int additionalRolesCount = qMax(visibleRoles().count() - 1, 0);
 115
 116     switch (m_itemLayout) {
 117     case IconsLayout: {
 118         const QString text = KStringHandler::preProcessWrap(values["name"].toString());
 119
 120         const qreal maxWidth = itemSize().width() - 2 * option.margin;
 121         int textLinesCount = 0;
 122         QTextLine line;
 123
 124         // Calculate the number of lines required for wrapping the name
 125         QTextOption textOption(Qt::AlignHCenter);
 126         textOption.setWrapMode(QTextOption::WrapAtWordBoundaryOrAnywhere);
 127
 128         QTextLayout layout(text, option.font);
 129         layout.setTextOption(textOption);
 130         layout.beginLayout();
 131         while ((line = layout.createLine()).isValid()) {
 132             line.setLineWidth(maxWidth);
 133             line.naturalTextWidth();
 134             ++textLinesCount;
 135         }
 136         layout.endLayout();
 137
 138         // Add one line for each additional information
 139         textLinesCount += additionalRolesCount;
 140
 141         const qreal height = textLinesCount * option.fontMetrics.height() +
 142                              option.iconSize +
 143                              option.margin * 4;
 144         return QSizeF(itemSize().width(), height);
 145     }
 146
 147     case CompactLayout: {
 148         // For each row exactly one role is shown. Calculate the maximum required width that is necessary
 149         // to show all roles without horizontal clipping.
 150         qreal maximumRequiredWidth = 0.0;
 151
 152         foreach (const QByteArray& role, visibleRoles()) {
 153             const QString text = KFileItemListWidget::roleText(role, values);
 154             const qreal requiredWidth = option.fontMetrics.width(text);
 155             maximumRequiredWidth = qMax(maximumRequiredWidth, requiredWidth);
 156         }
 157
 158         const qreal width = option.margin * 4 + option.iconSize + maximumRequiredWidth;
 159         const qreal height = option.margin * 2 + qMax(option.iconSize, (1 + additionalRolesCount) * option.fontMetrics.height());
 160         return QSizeF(width, height);
 161     }
 162
 163     case DetailsLayout: {
 164         // The width will be determined dynamically by KFileItemListView::visibleRoleSizes()
 165         const qreal height = option.margin * 2 + qMax(option.iconSize, option.fontMetrics.height());
 166         return QSizeF(-1, height);
 167     }
 168
 169     default:
 170         Q_ASSERT(false);
 171         break;
 172     }
 173
 174     return QSize();
 175 }
 176
 177 QHash<QByteArray, QSizeF> KFileItemListView::visibleRolesSizes(const KItemRangeList& itemRanges) const
 178 {
 179     QElapsedTimer timer;
 180     timer.start();
 181
 182     QHash<QByteArray, QSizeF> sizes;
 183
 184     int calculatedItemCount = 0;
 185     bool maxTimeExceeded = false;
 186     foreach (const KItemRange& itemRange, itemRanges) {
 187         const int startIndex = itemRange.index;
 188         const int endIndex = startIndex + itemRange.count - 1;
 189
 190         for (int i = startIndex; i <= endIndex; ++i) {
 191             foreach (const QByteArray& visibleRole, visibleRoles()) {
 192                 QSizeF maxSize = sizes.value(visibleRole, QSizeF(0, 0));
 193                 const QSizeF itemSize = visibleRoleSizeHint(i, visibleRole);
 194                 maxSize = maxSize.expandedTo(itemSize);
 195                 sizes.insert(visibleRole, maxSize);
 196             }
 197
 198             if (calculatedItemCount > 100 && timer.elapsed() > 200) {
 199                 // When having several thousands of items calculating the sizes can get
 200                 // very expensive. We accept a possibly too small role-size in favour
 201                 // of having no blocking user interface.
 202                 #ifdef KFILEITEMLISTVIEW_DEBUG
 203                     kDebug() << "Timer exceeded, stopped after" << calculatedItemCount << "items";
 204                 #endif
 205                 maxTimeExceeded = true;
 206                 break;
 207             }
 208             ++calculatedItemCount;
 209         }
 210         if (maxTimeExceeded) {
 211             break;
 212         }
 213     }
 214
 215 #ifdef KFILEITEMLISTVIEW_DEBUG
 216     int rangesItemCount = 0;
 217     foreach (const KItemRange& itemRange, itemRanges) {
 218         rangesItemCount += itemRange.count;
 219     }
 220     kDebug() << "[TIME] Calculated dynamic item size for " << rangesItemCount << "items:" << timer.elapsed();
 221 #endif
 222     return sizes;
 223 }
 224
 225 QPixmap KFileItemListView::createDragPixmap(const QSet<int>& indexes) const
 226 {
 227     if (!model()) {
 228         return QPixmap();
 229     }
 230
 231     const int itemCount = indexes.count();
 232     Q_ASSERT(itemCount > 0);
 233
 234     // If more than one item is dragged, align the items inside a
 235     // rectangular grid. The maximum grid size is limited to 5 x 5 items.
 236     int xCount;
 237     int size;
 238     if (itemCount > 16) {
 239         xCount = 5;
 240         size = KIconLoader::SizeSmall;
 241     } else if (itemCount > 9) {
 242         xCount = 4;
 243         size = KIconLoader::SizeSmallMedium;
 244     } else {
 245         xCount = 3;
 246         size = KIconLoader::SizeMedium;
 247     }
 248
 249     if (itemCount < xCount) {
 250         xCount = itemCount;
 251     }
 252
 253     int yCount = itemCount / xCount;
 254     if (itemCount % xCount != 0) {
 255         ++yCount;
 256     }
 257     if (yCount > xCount) {
 258         yCount = xCount;
 259     }
 260
 261     // Draw the selected items into the grid cells.
 262     QPixmap dragPixmap(xCount * size + xCount, yCount * size + yCount);
 263     dragPixmap.fill(Qt::transparent);
 264
 265     QPainter painter(&dragPixmap);
 266     int x = 0;
 267     int y = 0;
 268     QSetIterator<int> it(indexes);
 269     while (it.hasNext()) {
 270         const int index = it.next();
 271
 272         QPixmap pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 273         if (pixmap.isNull()) {
 274             KIcon icon(model()->data(index).value("iconName").toString());
 275             pixmap = icon.pixmap(size, size);
 276         } else {
 277             KPixmapModifier::scale(pixmap, QSize(size, size));
 278         }
 279
 280         painter.drawPixmap(x, y, pixmap);
 281
 282         x += size + 1;
 283         if (x >= dragPixmap.width()) {
 284             x = 0;
 285             y += size + 1;
 286         }
 287
 288         if (y >= dragPixmap.height()) {
 289             break;
 290         }
 291     }
 292
 293     return dragPixmap;
 294 }
 295
 296 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 297 {
 298     KFileItemListWidget* fileItemListWidget = static_cast<KFileItemListWidget*>(item);
 299
 300     switch (m_itemLayout) {
 301     case IconsLayout:   fileItemListWidget->setLayout(KFileItemListWidget::IconsLayout); break;
 302     case CompactLayout: fileItemListWidget->setLayout(KFileItemListWidget::CompactLayout); break;
 303     case DetailsLayout: fileItemListWidget->setLayout(KFileItemListWidget::DetailsLayout); break;
 304     default:            Q_ASSERT(false); break;
 305     }
 306
 307     fileItemListWidget->setAlternatingBackgroundColors(m_itemLayout == DetailsLayout &&
 308                                                        visibleRoles().count() > 1);
 309 }
 310
 311 bool KFileItemListView::itemSizeHintUpdateRequired(const QSet<QByteArray>& changedRoles) const
 312 {
 313     // Even if the icons have a different size they are always aligned within
 314     // the area defined by KItemStyleOption.iconSize and hence result in no
 315     // change of the item-size.
 316     const bool containsIconName = changedRoles.contains("iconName");
 317     const bool containsIconPixmap = changedRoles.contains("iconPixmap");
 318     const int count = changedRoles.count();
 319
 320     const bool iconChanged = (containsIconName && containsIconPixmap && count == 2) ||
 321                              (containsIconName && count == 1) ||
 322                              (containsIconPixmap && count == 1);
 323     return !iconChanged;
 324 }
 325
 326 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 327 {
 328     Q_UNUSED(previous);
 329     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 330
 331     if (m_modelRolesUpdater) {
 332         delete m_modelRolesUpdater;
 333     }
 334
 335     m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 336     const int size = styleOption().iconSize;
 337     m_modelRolesUpdater->setIconSize(QSize(size, size));
 338
 339     applyRolesToModel();
 340 }
 341
 342 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 343 {
 344     Q_UNUSED(current);
 345     Q_UNUSED(previous);
 346     updateLayoutOfVisibleItems();
 347 }
 348
 349 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 350 {
 351     Q_UNUSED(current);
 352     Q_UNUSED(previous);
 353     triggerVisibleIndexRangeUpdate();
 354 }
 355
 356 void KFileItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 357 {
 358     Q_UNUSED(current);
 359     Q_UNUSED(previous);
 360     triggerVisibleIndexRangeUpdate();
 361 }
 362
 363 void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 364 {
 365     Q_UNUSED(current);
 366     Q_UNUSED(previous);
 367     applyRolesToModel();
 368
 369     if (m_itemLayout == DetailsLayout) {
 370         // Only enable the alternating background colors if more than one role
 371         // is visible
 372         const int previousCount = previous.count();
 373         const int currentCount = current.count();
 374         if ((previousCount <= 1 && currentCount > 1) || (previousCount > 1 && currentCount <= 1)) {
 375             const bool enabled = (currentCount > 1);
 376             foreach (KItemListWidget* widget, visibleItemListWidgets()) {
 377                 widget->setAlternatingBackgroundColors(enabled);
 378             }
 379         }
 380     }
 381 }
 382
 383 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 384 {
 385     Q_UNUSED(current);
 386     Q_UNUSED(previous);
 387     triggerIconSizeUpdate();
 388 }
 389
 390 void KFileItemListView::onTransactionBegin()
 391 {
 392     m_modelRolesUpdater->setPaused(true);
 393 }
 394
 395 void KFileItemListView::onTransactionEnd()
 396 {
 397     // Only unpause the model-roles-updater if no timer is active. If one
 398     // timer is still active the model-roles-updater will be unpaused later as
 399     // soon as the timer has been exceeded.
 400     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 401                              m_updateIconSizeTimer->isActive();
 402     if (!timerActive) {
 403         m_modelRolesUpdater->setPaused(false);
 404     }
 405 }
 406
 407 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 408 {
 409     KItemListView::resizeEvent(event);
 410     triggerVisibleIndexRangeUpdate();
 411 }
 412
 413 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 414 {
 415     KItemListView::slotItemsRemoved(itemRanges);
 416     updateTimersInterval();
 417 }
 418
 419 void KFileItemListView::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
 420 {
 421     const QByteArray sortRole = model()->sortRole();
 422     if (!visibleRoles().contains(sortRole)) {
 423         applyRolesToModel();
 424     }
 425
 426     KItemListView::slotSortRoleChanged(current, previous);
 427 }
 428
 429 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 430 {
 431     if (!model()) {
 432         return;
 433     }
 434     m_modelRolesUpdater->setPaused(true);
 435     m_updateVisibleIndexRangeTimer->start();
 436 }
 437
 438 void KFileItemListView::updateVisibleIndexRange()
 439 {
 440     if (!m_modelRolesUpdater) {
 441         return;
 442     }
 443
 444     const int index = firstVisibleIndex();
 445     const int count = lastVisibleIndex() - index + 1;
 446     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 447
 448     if (m_updateIconSizeTimer->isActive()) {
 449         // If the icon-size update is pending do an immediate update
 450         // of the icon-size before unpausing m_modelRolesUpdater. This prevents
 451         // an unnecessary expensive recreation of all previews afterwards.
 452         m_updateIconSizeTimer->stop();
 453         const KItemListStyleOption& option = styleOption();
 454         m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 455     }
 456
 457     m_modelRolesUpdater->setPaused(isTransactionActive());
 458     updateTimersInterval();
 459 }
 460
 461 void KFileItemListView::triggerIconSizeUpdate()
 462 {
 463     if (!model()) {
 464         return;
 465     }
 466     m_modelRolesUpdater->setPaused(true);
 467     m_updateIconSizeTimer->start();
 468 }
 469
 470 void KFileItemListView::updateIconSize()
 471 {
 472     if (!m_modelRolesUpdater) {
 473         return;
 474     }
 475
 476     const KItemListStyleOption& option = styleOption();
 477     m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 478
 479     if (m_updateVisibleIndexRangeTimer->isActive()) {
 480         // If the visibility-index-range update is pending do an immediate update
 481         // of the range before unpausing m_modelRolesUpdater. This prevents
 482         // an unnecessary expensive recreation of all previews afterwards.
 483         m_updateVisibleIndexRangeTimer->stop();
 484         const int index = firstVisibleIndex();
 485         const int count = lastVisibleIndex() - index + 1;
 486         m_modelRolesUpdater->setVisibleIndexRange(index, count);
 487     }
 488
 489     m_modelRolesUpdater->setPaused(isTransactionActive());
 490     updateTimersInterval();
 491 }
 492
 493 QSizeF KFileItemListView::visibleRoleSizeHint(int index, const QByteArray& role) const
 494 {
 495     const KItemListStyleOption& option = styleOption();
 496
 497     qreal width = m_minimumRolesWidths.value(role, 0);
 498     const qreal height = option.margin * 2 + option.fontMetrics.height();
 499
 500     const QHash<QByteArray, QVariant> values = model()->data(index);
 501     const QString text = KFileItemListWidget::roleText(role, values);
 502     if (!text.isEmpty()) {
 503         const qreal columnMargin = option.margin * 3;
 504         width = qMax(width, qreal(2 * columnMargin + option.fontMetrics.width(text)));
 505     }
 506
 507     if (role == "name") {
 508         // Increase the width by the expansion-toggle and the current expansion level
 509         const int expansionLevel = values.value("expansionLevel", 0).toInt();
 510         width += option.margin + expansionLevel * itemSize().height() + KIconLoader::SizeSmall;
 511
 512         // Increase the width by the required space for the icon
 513         width += option.margin * 2 + option.iconSize;
 514     }
 515
 516     return QSizeF(width, height);
 517 }
 518
 519 void KFileItemListView::updateLayoutOfVisibleItems()
 520 {
 521     if (!model()) {
 522         return;
 523     }
 524
 525     foreach (KItemListWidget* widget, visibleItemListWidgets()) {
 526         initializeItemListWidget(widget);
 527     }
 528     triggerVisibleIndexRangeUpdate();
 529 }
 530
 531 void KFileItemListView::updateTimersInterval()
 532 {
 533     if (!model()) {
 534         return;
 535     }
 536
 537     // The ShortInterval is used for cases like switching the directory: If the
 538     // model is empty and filled later the creation of the previews should be done
 539     // as soon as possible. The LongInterval is used when the model already contains
 540     // items and assures that operations like zooming don't result in too many temporary
 541     // recreations of the previews.
 542
 543     const int interval = (model()->count() <= 0) ? ShortInterval : LongInterval;
 544     m_updateVisibleIndexRangeTimer->setInterval(interval);
 545     m_updateIconSizeTimer->setInterval(interval);
 546 }
 547
 548 void KFileItemListView::updateMinimumRolesWidths()
 549 {
 550     m_minimumRolesWidths.clear();
 551
 552     const KItemListStyleOption& option = styleOption();
 553     const QString sizeText = QLatin1String("888888") + i18nc("@item:intable", "items");
 554     m_minimumRolesWidths.insert("size", option.fontMetrics.width(sizeText));
 555 }
 556
 557 void KFileItemListView::applyRolesToModel()
 558 {
 559     if (!model()) {
 560         return;
 561     }
 562
 563     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 564     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 565
 566     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 567     // Add all roles that are mandatory for having a working KFileItemListView:
 568     QSet<QByteArray> roles = visibleRoles().toSet();
 569     roles.insert("iconPixmap");
 570     roles.insert("iconName");
 571     roles.insert("name");
 572     roles.insert("isDir");
 573     if (m_itemLayout == DetailsLayout) {
 574         roles.insert("isExpanded");
 575         roles.insert("expansionLevel");
 576     }
 577
 578     // Assure that the role that is used for sorting will be determined
 579     roles.insert(fileItemModel->sortRole());
 580
 581     fileItemModel->setRoles(roles);
 582     m_modelRolesUpdater->setRoles(roles);
 583 }
 584
 585 #include "kfileitemlistview.moc"