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