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 = values[role].toString();
 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::visibleRoleSizes() 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 #ifdef KFILEITEMLISTVIEW_DEBUG
 198     kDebug() << "[TIME] Calculated dynamic item size for " << itemCount << "items:" << timer.elapsed();
 199 #endif
 200     return sizes;
 201 }
 202
 203 QPixmap KFileItemListView::createDragPixmap(const QSet<int>& indexes) const
 204 {
 205     QPixmap pixmap;
 206
 207     if (model()) {
 208         QSetIterator<int> it(indexes);
 209         while (it.hasNext()) {
 210             const int index = it.next();
 211             // TODO: Only one item is considered currently
 212             pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 213             if (pixmap.isNull()) {
 214                 KIcon icon(model()->data(index).value("iconName").toString());
 215                 pixmap = icon.pixmap(itemSize().toSize());
 216             }
 217         }
 218     }
 219
 220     return pixmap;
 221 }
 222
 223 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 224 {
 225     KFileItemListWidget* fileItemListWidget = static_cast<KFileItemListWidget*>(item);
 226
 227     switch (m_itemLayout) {
 228     case IconsLayout:   fileItemListWidget->setLayout(KFileItemListWidget::IconsLayout); break;
 229     case CompactLayout: fileItemListWidget->setLayout(KFileItemListWidget::CompactLayout); break;
 230     case DetailsLayout: fileItemListWidget->setLayout(KFileItemListWidget::DetailsLayout); break;
 231     default:            Q_ASSERT(false); break;
 232     }
 233 }
 234
 235 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 236 {
 237     Q_UNUSED(previous);
 238     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 239
 240     if (m_modelRolesUpdater) {
 241         delete m_modelRolesUpdater;
 242     }
 243
 244     m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 245     const int size = styleOption().iconSize;
 246     m_modelRolesUpdater->setIconSize(QSize(size, size));
 247 }
 248
 249 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 250 {
 251     Q_UNUSED(current);
 252     Q_UNUSED(previous);
 253     updateLayoutOfVisibleItems();
 254 }
 255
 256 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 257 {
 258     Q_UNUSED(current);
 259     Q_UNUSED(previous);
 260     triggerVisibleIndexRangeUpdate();
 261 }
 262
 263 void KFileItemListView::onOffsetChanged(qreal current, qreal previous)
 264 {
 265     Q_UNUSED(current);
 266     Q_UNUSED(previous);
 267     triggerVisibleIndexRangeUpdate();
 268 }
 269
 270 void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 271 {
 272     Q_UNUSED(previous);
 273
 274     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 275     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 276
 277     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 278     // Add all roles that are mandatory for having a working KFileItemListView:
 279     QSet<QByteArray> keys = current.toSet();
 280     QSet<QByteArray> roles = keys;
 281     roles.insert("iconPixmap");
 282     roles.insert("iconName");
 283     roles.insert("name"); // TODO: just don't allow to disable it
 284     roles.insert("isDir");
 285     if (m_itemLayout == DetailsLayout) {
 286         roles.insert("isExpanded");
 287         roles.insert("expansionLevel");
 288     }
 289
 290     fileItemModel->setRoles(roles);
 291
 292     m_modelRolesUpdater->setRoles(keys);
 293 }
 294
 295 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 296 {
 297     Q_UNUSED(current);
 298     Q_UNUSED(previous);
 299     triggerIconSizeUpdate();
 300 }
 301
 302 void KFileItemListView::onTransactionBegin()
 303 {
 304     m_modelRolesUpdater->setPaused(true);
 305 }
 306
 307 void KFileItemListView::onTransactionEnd()
 308 {
 309     // Only unpause the model-roles-updater if no timer is active. If one
 310     // timer is still active the model-roles-updater will be unpaused later as
 311     // soon as the timer has been exceeded.
 312     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 313                              m_updateIconSizeTimer->isActive();
 314     if (!timerActive) {
 315         m_modelRolesUpdater->setPaused(false);
 316     }
 317 }
 318
 319 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 320 {
 321     KItemListView::resizeEvent(event);
 322     triggerVisibleIndexRangeUpdate();
 323 }
 324
 325 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 326 {
 327     KItemListView::slotItemsRemoved(itemRanges);
 328     updateTimersInterval();
 329 }
 330
 331 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 332 {
 333     m_modelRolesUpdater->setPaused(true);
 334     m_updateVisibleIndexRangeTimer->start();
 335 }
 336
 337 void KFileItemListView::updateVisibleIndexRange()
 338 {
 339     if (!m_modelRolesUpdater) {
 340         return;
 341     }
 342
 343     const int index = firstVisibleIndex();
 344     const int count = lastVisibleIndex() - index + 1;
 345     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 346
 347     if (m_updateIconSizeTimer->isActive()) {
 348         // If the icon-size update is pending do an immediate update
 349         // of the icon-size before unpausing m_modelRolesUpdater. This prevents
 350         // an unnecessary expensive recreation of all previews afterwards.
 351         m_updateIconSizeTimer->stop();
 352         const KItemListStyleOption& option = styleOption();
 353         m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 354     }
 355
 356     m_modelRolesUpdater->setPaused(isTransactionActive());
 357     updateTimersInterval();
 358 }
 359
 360 void KFileItemListView::triggerIconSizeUpdate()
 361 {
 362     m_modelRolesUpdater->setPaused(true);
 363     m_updateIconSizeTimer->start();
 364 }
 365
 366 void KFileItemListView::updateIconSize()
 367 {
 368     if (!m_modelRolesUpdater) {
 369         return;
 370     }
 371
 372     const KItemListStyleOption& option = styleOption();
 373     m_modelRolesUpdater->setIconSize(QSize(option.iconSize, option.iconSize));
 374
 375     if (m_updateVisibleIndexRangeTimer->isActive()) {
 376         // If the visibility-index-range update is pending do an immediate update
 377         // of the range before unpausing m_modelRolesUpdater. This prevents
 378         // an unnecessary expensive recreation of all previews afterwards.
 379         m_updateVisibleIndexRangeTimer->stop();
 380         const int index = firstVisibleIndex();
 381         const int count = lastVisibleIndex() - index + 1;
 382         m_modelRolesUpdater->setVisibleIndexRange(index, count);
 383     }
 384
 385     m_modelRolesUpdater->setPaused(isTransactionActive());
 386     updateTimersInterval();
 387 }
 388
 389 QSizeF KFileItemListView::visibleRoleSizeHint(int index, const QByteArray& role) const
 390 {
 391     const KItemListStyleOption& option = styleOption();
 392
 393     qreal width = m_minimumRolesWidths.value(role, 0);
 394     const qreal height = option.margin * 2 + option.fontMetrics.height();
 395
 396     const QVariant value = model()->data(index).value(role);
 397     const QString text = value.toString();
 398     if (!text.isEmpty()) {
 399         const qreal columnMargin = option.margin * 3;
 400         width = qMax(width, qreal(2 * columnMargin + option.fontMetrics.width(text)));
 401     }
 402
 403     if (role == "name") {
 404         const QHash<QByteArray, QVariant> values = model()->data(index);
 405         Q_ASSERT(values.contains("expansionLevel"));
 406
 407         // Increase the width by the expansion-toggle and the current expansion level
 408         const int expansionLevel = values.value("expansionLevel", 0).toInt();
 409         width += option.margin + expansionLevel * itemSize().height() + KIconLoader::SizeSmall;
 410
 411         // Increase the width by the required space for the icon
 412         width += option.margin * 2 + option.iconSize;
 413     }
 414
 415     return QSizeF(width, height);
 416 }
 417
 418 void KFileItemListView::updateLayoutOfVisibleItems()
 419 {
 420     foreach (KItemListWidget* widget, visibleItemListWidgets()) {
 421         initializeItemListWidget(widget);
 422     }
 423     triggerVisibleIndexRangeUpdate();
 424 }
 425
 426 void KFileItemListView::updateTimersInterval()
 427 {
 428     if (!model()) {
 429         return;
 430     }
 431
 432     // The ShortInterval is used for cases like switching the directory: If the
 433     // model is empty and filled later the creation of the previews should be done
 434     // as soon as possible. The LongInterval is used when the model already contains
 435     // items and assures that operations like zooming don't result in too many temporary
 436     // recreations of the previews.
 437
 438     const int interval = (model()->count() <= 0) ? ShortInterval : LongInterval;
 439     m_updateVisibleIndexRangeTimer->setInterval(interval);
 440     m_updateIconSizeTimer->setInterval(interval);
 441 }
 442
 443 void KFileItemListView::updateMinimumRolesWidths()
 444 {
 445     m_minimumRolesWidths.clear();
 446
 447     const KItemListStyleOption& option = styleOption();
 448     const QString sizeText = QLatin1String("888888") + i18nc("@item:intable", "items");
 449     m_minimumRolesWidths.insert("size", option.fontMetrics.width(sizeText));
 450 }
 451
 452 #include "kfileitemlistview.moc"