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 "kfileitemlistwidget.h"
  23 #include "kfileitemmodel.h"
  24 #include "kfileitemmodelrolesupdater.h"
  25 #include "private/kpixmapmodifier.h"
  26
  27 #include <KIconLoader>
  28
  29 #include <QGraphicsScene>
  30 #include <QGraphicsView>
  31 #include <QPainter>
  32 #include <QTimer>
  33
  34 // #define KFILEITEMLISTVIEW_DEBUG
  35
  36 namespace {
  37     // If the visible index range changes, KFileItemModelRolesUpdater is not
  38     // informed immediately, but with a short delay. This ensures that scrolling
  39     // always feels smooth and is not interrupted by icon loading (which can be
  40     // quite expensive if a disk access is required to determine the final icon).
  41     const int ShortInterval = 50;
  42
  43     // If the icon size changes, a longer delay is used. This prevents that
  44     // the expensive re-generation of all previews is triggered repeatedly when
  45     // changing the zoom level.
  46     const int LongInterval = 300;
  47 }
  48
  49 KFileItemListView::KFileItemListView(QGraphicsWidget* parent) :
  50     KStandardItemListView(parent),
  51     m_modelRolesUpdater(nullptr),
  52     m_updateVisibleIndexRangeTimer(nullptr),
  53     m_updateIconSizeTimer(nullptr)
  54 {
  55     setAcceptDrops(true);
  56
  57     setScrollOrientation(Qt::Vertical);
  58
  59     m_updateVisibleIndexRangeTimer = new QTimer(this);
  60     m_updateVisibleIndexRangeTimer->setSingleShot(true);
  61     m_updateVisibleIndexRangeTimer->setInterval(ShortInterval);
  62     connect(m_updateVisibleIndexRangeTimer, &QTimer::timeout, this, &KFileItemListView::updateVisibleIndexRange);
  63
  64     m_updateIconSizeTimer = new QTimer(this);
  65     m_updateIconSizeTimer->setSingleShot(true);
  66     m_updateIconSizeTimer->setInterval(LongInterval);
  67     connect(m_updateIconSizeTimer, &QTimer::timeout, this, &KFileItemListView::updateIconSize);
  68
  69     setVisibleRoles({"text"});
  70 }
  71
  72 KFileItemListView::~KFileItemListView()
  73 {
  74 }
  75
  76 void KFileItemListView::setPreviewsShown(bool show)
  77 {
  78     if (!m_modelRolesUpdater) {
  79         return;
  80     }
  81
  82     if (m_modelRolesUpdater->previewsShown() != show) {
  83         beginTransaction();
  84         m_modelRolesUpdater->setPreviewsShown(show);
  85         onPreviewsShownChanged(show);
  86         endTransaction();
  87     }
  88 }
  89
  90 bool KFileItemListView::previewsShown() const
  91 {
  92     return m_modelRolesUpdater ? m_modelRolesUpdater->previewsShown() : false;
  93 }
  94
  95 void KFileItemListView::setEnlargeSmallPreviews(bool enlarge)
  96 {
  97     if (m_modelRolesUpdater) {
  98         m_modelRolesUpdater->setEnlargeSmallPreviews(enlarge);
  99     }
 100 }
 101
 102 bool KFileItemListView::enlargeSmallPreviews() const
 103 {
 104     return m_modelRolesUpdater ? m_modelRolesUpdater->enlargeSmallPreviews() : false;
 105 }
 106
 107 void KFileItemListView::setEnabledPlugins(const QStringList& list)
 108 {
 109     if (m_modelRolesUpdater) {
 110         m_modelRolesUpdater->setEnabledPlugins(list);
 111     }
 112 }
 113
 114 QStringList KFileItemListView::enabledPlugins() const
 115 {
 116     return m_modelRolesUpdater ? m_modelRolesUpdater->enabledPlugins() : QStringList();
 117 }
 118
 119 QPixmap KFileItemListView::createDragPixmap(const KItemSet& indexes) const
 120 {
 121     if (!model()) {
 122         return QPixmap();
 123     }
 124
 125     const int itemCount = indexes.count();
 126     Q_ASSERT(itemCount > 0);
 127     if (itemCount == 1) {
 128         return KItemListView::createDragPixmap(indexes);
 129     }
 130
 131     // If more than one item is dragged, align the items inside a
 132     // rectangular grid. The maximum grid size is limited to 5 x 5 items.
 133     int xCount;
 134     int size;
 135     if (itemCount > 16) {
 136         xCount = 5;
 137         size = KIconLoader::SizeSmall;
 138     } else if (itemCount > 9) {
 139         xCount = 4;
 140         size = KIconLoader::SizeSmallMedium;
 141     } else {
 142         xCount = 3;
 143         size = KIconLoader::SizeMedium;
 144     }
 145
 146     if (itemCount < xCount) {
 147         xCount = itemCount;
 148     }
 149
 150     int yCount = itemCount / xCount;
 151     if (itemCount % xCount != 0) {
 152         ++yCount;
 153     }
 154     if (yCount > xCount) {
 155         yCount = xCount;
 156     }
 157
 158     const qreal dpr = scene()->views()[0]->devicePixelRatio();
 159     // Draw the selected items into the grid cells.
 160     QPixmap dragPixmap(QSize(xCount * size + xCount, yCount * size + yCount) * dpr);
 161     dragPixmap.setDevicePixelRatio(dpr);
 162     dragPixmap.fill(Qt::transparent);
 163
 164     QPainter painter(&dragPixmap);
 165     int x = 0;
 166     int y = 0;
 167
 168     for (int index : indexes) {
 169         QPixmap pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 170         if (pixmap.isNull()) {
 171             QIcon icon = QIcon::fromTheme(model()->data(index).value("iconName").toString());
 172             pixmap = icon.pixmap(size, size);
 173         } else {
 174             KPixmapModifier::scale(pixmap, QSize(size, size) * dpr);
 175         }
 176
 177         painter.drawPixmap(x, y, pixmap);
 178
 179         x += size + 1;
 180         if (x >= dragPixmap.width()) {
 181             x = 0;
 182             y += size + 1;
 183         }
 184
 185         if (y >= dragPixmap.height()) {
 186             break;
 187         }
 188     }
 189
 190     return dragPixmap;
 191 }
 192
 193 KItemListWidgetCreatorBase* KFileItemListView::defaultWidgetCreator() const
 194 {
 195     return new KItemListWidgetCreator<KFileItemListWidget>();
 196 }
 197
 198 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 199 {
 200     KStandardItemListView::initializeItemListWidget(item);
 201
 202     // Make sure that the item has an icon.
 203     QHash<QByteArray, QVariant> data = item->data();
 204     if (!data.contains("iconName") && data["iconPixmap"].value<QPixmap>().isNull()) {
 205         Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 206         KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 207
 208         const KFileItem fileItem = fileItemModel->fileItem(item->index());
 209         data.insert("iconName", fileItem.iconName());
 210         item->setData(data, {"iconName"});
 211     }
 212 }
 213
 214 void KFileItemListView::onPreviewsShownChanged(bool shown)
 215 {
 216     Q_UNUSED(shown)
 217 }
 218
 219 void KFileItemListView::onItemLayoutChanged(ItemLayout current, ItemLayout previous)
 220 {
 221     KStandardItemListView::onItemLayoutChanged(current, previous);
 222     triggerVisibleIndexRangeUpdate();
 223 }
 224
 225 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 226 {
 227     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 228     KStandardItemListView::onModelChanged(current, previous);
 229
 230     delete m_modelRolesUpdater;
 231     m_modelRolesUpdater = nullptr;
 232
 233     if (current) {
 234         m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 235         m_modelRolesUpdater->setIconSize(availableIconSize());
 236
 237         applyRolesToModel();
 238     }
 239 }
 240
 241 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 242 {
 243     KStandardItemListView::onScrollOrientationChanged(current, previous);
 244     triggerVisibleIndexRangeUpdate();
 245 }
 246
 247 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 248 {
 249     Q_UNUSED(current)
 250     Q_UNUSED(previous)
 251     triggerVisibleIndexRangeUpdate();
 252 }
 253
 254 void KFileItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 255 {
 256     KStandardItemListView::onScrollOffsetChanged(current, previous);
 257     triggerVisibleIndexRangeUpdate();
 258 }
 259
 260 void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 261 {
 262     KStandardItemListView::onVisibleRolesChanged(current, previous);
 263     applyRolesToModel();
 264 }
 265
 266 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 267 {
 268     KStandardItemListView::onStyleOptionChanged(current, previous);
 269     triggerIconSizeUpdate();
 270 }
 271
 272 void KFileItemListView::onSupportsItemExpandingChanged(bool supportsExpanding)
 273 {
 274     applyRolesToModel();
 275     KStandardItemListView::onSupportsItemExpandingChanged(supportsExpanding);
 276     triggerVisibleIndexRangeUpdate();
 277 }
 278
 279 void KFileItemListView::onTransactionBegin()
 280 {
 281     if (m_modelRolesUpdater) {
 282         m_modelRolesUpdater->setPaused(true);
 283     }
 284 }
 285
 286 void KFileItemListView::onTransactionEnd()
 287 {
 288     if (!m_modelRolesUpdater) {
 289         return;
 290     }
 291
 292     // Only unpause the model-roles-updater if no timer is active. If one
 293     // timer is still active the model-roles-updater will be unpaused later as
 294     // soon as the timer has been exceeded.
 295     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 296                              m_updateIconSizeTimer->isActive();
 297     if (!timerActive) {
 298         m_modelRolesUpdater->setPaused(false);
 299     }
 300 }
 301
 302 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 303 {
 304     KStandardItemListView::resizeEvent(event);
 305     triggerVisibleIndexRangeUpdate();
 306 }
 307
 308 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 309 {
 310     KStandardItemListView::slotItemsRemoved(itemRanges);
 311 }
 312
 313 void KFileItemListView::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
 314 {
 315     const QByteArray sortRole = model()->sortRole();
 316     if (!visibleRoles().contains(sortRole)) {
 317         applyRolesToModel();
 318     }
 319
 320     KStandardItemListView::slotSortRoleChanged(current, previous);
 321 }
 322
 323 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 324 {
 325     if (!model()) {
 326         return;
 327     }
 328     m_modelRolesUpdater->setPaused(true);
 329
 330     // If the icon size has been changed recently, wait until
 331     // m_updateIconSizeTimer expires.
 332     if (!m_updateIconSizeTimer->isActive()) {
 333         m_updateVisibleIndexRangeTimer->start();
 334     }
 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->setMaximumVisibleItems(maximumVisibleItems());
 346     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 347     m_modelRolesUpdater->setPaused(isTransactionActive());
 348 }
 349
 350 void KFileItemListView::triggerIconSizeUpdate()
 351 {
 352     if (!model()) {
 353         return;
 354     }
 355     m_modelRolesUpdater->setPaused(true);
 356     m_updateIconSizeTimer->start();
 357
 358     // The visible index range will be updated when m_updateIconSizeTimer expires.
 359     // Stop m_updateVisibleIndexRangeTimer to prevent an expensive re-generation
 360     // of all previews (note that the user might change the icon size again soon).
 361     m_updateVisibleIndexRangeTimer->stop();
 362 }
 363
 364 void KFileItemListView::updateIconSize()
 365 {
 366     if (!m_modelRolesUpdater) {
 367         return;
 368     }
 369
 370     m_modelRolesUpdater->setIconSize(availableIconSize());
 371
 372     // Update the visible index range (which has most likely changed after the
 373     // icon size change) before unpausing m_modelRolesUpdater.
 374     const int index = firstVisibleIndex();
 375     const int count = lastVisibleIndex() - index + 1;
 376     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 377
 378     m_modelRolesUpdater->setPaused(isTransactionActive());
 379 }
 380
 381 void KFileItemListView::applyRolesToModel()
 382 {
 383     if (!model()) {
 384         return;
 385     }
 386
 387     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 388     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 389
 390     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 391     // Add all roles that are mandatory for having a working KFileItemListView:
 392     QSet<QByteArray> roles = visibleRoles().toSet();
 393     roles.insert("iconPixmap");
 394     roles.insert("iconName");
 395     roles.insert("text");
 396     roles.insert("isDir");
 397     roles.insert("isLink");
 398     roles.insert("isHidden");
 399     if (supportsItemExpanding()) {
 400         roles.insert("isExpanded");
 401         roles.insert("isExpandable");
 402         roles.insert("expandedParentsCount");
 403     }
 404
 405     // Assure that the role that is used for sorting will be determined
 406     roles.insert(fileItemModel->sortRole());
 407
 408     fileItemModel->setRoles(roles);
 409     m_modelRolesUpdater->setRoles(roles);
 410 }
 411
 412 QSize KFileItemListView::availableIconSize() const
 413 {
 414     const KItemListStyleOption& option = styleOption();
 415     const int iconSize = option.iconSize;
 416     if (itemLayout() == IconsLayout) {
 417         const int maxIconWidth = itemSize().width() - 2 * option.padding;
 418         return QSize(maxIconWidth, iconSize);
 419     }
 420
 421     return QSize(iconSize, iconSize);
 422 }
 423