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 "kfileitemmodelrolesupdater.h"
  23 #include "kfileitemlistwidget.h"
  24 #include "kfileitemmodel.h"
  25 #include "private/kpixmapmodifier.h"
  26
  27 #include <QIcon>
  28 #include <KIconLoader>
  29
  30 #include <QPainter>
  31 #include <QTimer>
  32
  33 // #define KFILEITEMLISTVIEW_DEBUG
  34
  35 namespace {
  36     // If the visible index range changes, KFileItemModelRolesUpdater is not
  37     // informed immediatetly, but with a short delay. This ensures that scrolling
  38     // always feels smooth and is not interrupted by icon loading (which can be
  39     // quite expensive if a disk access is required to determine the final icon).
  40     const int ShortInterval = 50;
  41
  42     // If the icon size changes, a longer delay is used. This prevents that
  43     // the expensive re-generation of all previews is triggered repeatedly when
  44     // chaning the zoom level.
  45     const int LongInterval = 300;
  46 }
  47
  48 KFileItemListView::KFileItemListView(QGraphicsWidget* parent) :
  49     KStandardItemListView(parent),
  50     m_modelRolesUpdater(0),
  51     m_updateVisibleIndexRangeTimer(0),
  52     m_updateIconSizeTimer(0)
  53 {
  54     setAcceptDrops(true);
  55
  56     setScrollOrientation(Qt::Vertical);
  57
  58     m_updateVisibleIndexRangeTimer = new QTimer(this);
  59     m_updateVisibleIndexRangeTimer->setSingleShot(true);
  60     m_updateVisibleIndexRangeTimer->setInterval(ShortInterval);
  61     connect(m_updateVisibleIndexRangeTimer, &QTimer::timeout, this, &KFileItemListView::updateVisibleIndexRange);
  62
  63     m_updateIconSizeTimer = new QTimer(this);
  64     m_updateIconSizeTimer->setSingleShot(true);
  65     m_updateIconSizeTimer->setInterval(LongInterval);
  66     connect(m_updateIconSizeTimer, &QTimer::timeout, this, &KFileItemListView::updateIconSize);
  67
  68     setVisibleRoles({"text"});
  69 }
  70
  71 KFileItemListView::~KFileItemListView()
  72 {
  73 }
  74
  75 void KFileItemListView::setPreviewsShown(bool show)
  76 {
  77     if (!m_modelRolesUpdater) {
  78         return;
  79     }
  80
  81     if (m_modelRolesUpdater->previewsShown() != show) {
  82         beginTransaction();
  83         m_modelRolesUpdater->setPreviewsShown(show);
  84         onPreviewsShownChanged(show);
  85         endTransaction();
  86     }
  87 }
  88
  89 bool KFileItemListView::previewsShown() const
  90 {
  91     return m_modelRolesUpdater ? m_modelRolesUpdater->previewsShown() : false;
  92 }
  93
  94 void KFileItemListView::setEnlargeSmallPreviews(bool enlarge)
  95 {
  96     if (m_modelRolesUpdater) {
  97         m_modelRolesUpdater->setEnlargeSmallPreviews(enlarge);
  98     }
  99 }
 100
 101 bool KFileItemListView::enlargeSmallPreviews() const
 102 {
 103     return m_modelRolesUpdater ? m_modelRolesUpdater->enlargeSmallPreviews() : false;
 104 }
 105
 106 void KFileItemListView::setEnabledPlugins(const QStringList& list)
 107 {
 108     if (m_modelRolesUpdater) {
 109         m_modelRolesUpdater->setEnabledPlugins(list);
 110     }
 111 }
 112
 113 QStringList KFileItemListView::enabledPlugins() const
 114 {
 115     return m_modelRolesUpdater ? m_modelRolesUpdater->enabledPlugins() : QStringList();
 116 }
 117
 118 QPixmap KFileItemListView::createDragPixmap(const KItemSet& indexes) const
 119 {
 120     if (!model()) {
 121         return QPixmap();
 122     }
 123
 124     const int itemCount = indexes.count();
 125     Q_ASSERT(itemCount > 0);
 126     if (itemCount == 1) {
 127         return KItemListView::createDragPixmap(indexes);
 128     }
 129
 130     // If more than one item is dragged, align the items inside a
 131     // rectangular grid. The maximum grid size is limited to 5 x 5 items.
 132     int xCount;
 133     int size;
 134     if (itemCount > 16) {
 135         xCount = 5;
 136         size = KIconLoader::SizeSmall;
 137     } else if (itemCount > 9) {
 138         xCount = 4;
 139         size = KIconLoader::SizeSmallMedium;
 140     } else {
 141         xCount = 3;
 142         size = KIconLoader::SizeMedium;
 143     }
 144
 145     if (itemCount < xCount) {
 146         xCount = itemCount;
 147     }
 148
 149     int yCount = itemCount / xCount;
 150     if (itemCount % xCount != 0) {
 151         ++yCount;
 152     }
 153     if (yCount > xCount) {
 154         yCount = xCount;
 155     }
 156
 157     // Draw the selected items into the grid cells.
 158     QPixmap dragPixmap(xCount * size + xCount, yCount * size + yCount);
 159     dragPixmap.fill(Qt::transparent);
 160
 161     QPainter painter(&dragPixmap);
 162     int x = 0;
 163     int y = 0;
 164
 165     foreach (int index, indexes) {
 166         QPixmap pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 167         if (pixmap.isNull()) {
 168             QIcon icon = QIcon::fromTheme(model()->data(index).value("iconName").toString());
 169             pixmap = icon.pixmap(size, size);
 170         } else {
 171             KPixmapModifier::scale(pixmap, QSize(size, size));
 172         }
 173
 174         painter.drawPixmap(x, y, pixmap);
 175
 176         x += size + 1;
 177         if (x >= dragPixmap.width()) {
 178             x = 0;
 179             y += size + 1;
 180         }
 181
 182         if (y >= dragPixmap.height()) {
 183             break;
 184         }
 185     }
 186
 187     return dragPixmap;
 188 }
 189
 190 KItemListWidgetCreatorBase* KFileItemListView::defaultWidgetCreator() const
 191 {
 192     return new KItemListWidgetCreator<KFileItemListWidget>();
 193 }
 194
 195 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 196 {
 197     KStandardItemListView::initializeItemListWidget(item);
 198
 199     // Make sure that the item has an icon.
 200     QHash<QByteArray, QVariant> data = item->data();
 201     if (!data.contains("iconName") && data["iconPixmap"].value<QPixmap>().isNull()) {
 202         Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 203         KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 204
 205         const KFileItem fileItem = fileItemModel->fileItem(item->index());
 206         data.insert("iconName", fileItem.iconName());
 207         item->setData(data, {"iconName"});
 208     }
 209 }
 210
 211 void KFileItemListView::onPreviewsShownChanged(bool shown)
 212 {
 213     Q_UNUSED(shown);
 214 }
 215
 216 void KFileItemListView::onItemLayoutChanged(ItemLayout current, ItemLayout previous)
 217 {
 218     KStandardItemListView::onItemLayoutChanged(current, previous);
 219     triggerVisibleIndexRangeUpdate();
 220 }
 221
 222 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 223 {
 224     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 225     KStandardItemListView::onModelChanged(current, previous);
 226
 227     delete m_modelRolesUpdater;
 228     m_modelRolesUpdater = 0;
 229
 230     if (current) {
 231         m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 232         m_modelRolesUpdater->setIconSize(availableIconSize());
 233
 234         applyRolesToModel();
 235     }
 236 }
 237
 238 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 239 {
 240     KStandardItemListView::onScrollOrientationChanged(current, previous);
 241     triggerVisibleIndexRangeUpdate();
 242 }
 243
 244 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 245 {
 246     Q_UNUSED(current);
 247     Q_UNUSED(previous);
 248     triggerVisibleIndexRangeUpdate();
 249 }
 250
 251 void KFileItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 252 {
 253     KStandardItemListView::onScrollOffsetChanged(current, previous);
 254     triggerVisibleIndexRangeUpdate();
 255 }
 256
 257 void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 258 {
 259     KStandardItemListView::onVisibleRolesChanged(current, previous);
 260     applyRolesToModel();
 261 }
 262
 263 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 264 {
 265     KStandardItemListView::onStyleOptionChanged(current, previous);
 266     triggerIconSizeUpdate();
 267 }
 268
 269 void KFileItemListView::onSupportsItemExpandingChanged(bool supportsExpanding)
 270 {
 271     applyRolesToModel();
 272     KStandardItemListView::onSupportsItemExpandingChanged(supportsExpanding);
 273     triggerVisibleIndexRangeUpdate();
 274 }
 275
 276 void KFileItemListView::onTransactionBegin()
 277 {
 278     if (m_modelRolesUpdater) {
 279         m_modelRolesUpdater->setPaused(true);
 280     }
 281 }
 282
 283 void KFileItemListView::onTransactionEnd()
 284 {
 285     if (!m_modelRolesUpdater) {
 286         return;
 287     }
 288
 289     // Only unpause the model-roles-updater if no timer is active. If one
 290     // timer is still active the model-roles-updater will be unpaused later as
 291     // soon as the timer has been exceeded.
 292     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 293                              m_updateIconSizeTimer->isActive();
 294     if (!timerActive) {
 295         m_modelRolesUpdater->setPaused(false);
 296     }
 297 }
 298
 299 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 300 {
 301     KStandardItemListView::resizeEvent(event);
 302     triggerVisibleIndexRangeUpdate();
 303 }
 304
 305 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 306 {
 307     KStandardItemListView::slotItemsRemoved(itemRanges);
 308 }
 309
 310 void KFileItemListView::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
 311 {
 312     const QByteArray sortRole = model()->sortRole();
 313     if (!visibleRoles().contains(sortRole)) {
 314         applyRolesToModel();
 315     }
 316
 317     KStandardItemListView::slotSortRoleChanged(current, previous);
 318 }
 319
 320 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 321 {
 322     if (!model()) {
 323         return;
 324     }
 325     m_modelRolesUpdater->setPaused(true);
 326
 327     // If the icon size has been changed recently, wait until
 328     // m_updateIconSizeTimer expires.
 329     if (!m_updateIconSizeTimer->isActive()) {
 330         m_updateVisibleIndexRangeTimer->start();
 331     }
 332 }
 333
 334 void KFileItemListView::updateVisibleIndexRange()
 335 {
 336     if (!m_modelRolesUpdater) {
 337         return;
 338     }
 339
 340     const int index = firstVisibleIndex();
 341     const int count = lastVisibleIndex() - index + 1;
 342     m_modelRolesUpdater->setMaximumVisibleItems(maximumVisibleItems());
 343     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 344     m_modelRolesUpdater->setPaused(isTransactionActive());
 345 }
 346
 347 void KFileItemListView::triggerIconSizeUpdate()
 348 {
 349     if (!model()) {
 350         return;
 351     }
 352     m_modelRolesUpdater->setPaused(true);
 353     m_updateIconSizeTimer->start();
 354
 355     // The visible index range will be updated when m_updateIconSizeTimer expires.
 356     // Stop m_updateVisibleIndexRangeTimer to prevent an expensive re-generation
 357     // of all previews (note that the user might change the icon size again soon).
 358     m_updateVisibleIndexRangeTimer->stop();
 359 }
 360
 361 void KFileItemListView::updateIconSize()
 362 {
 363     if (!m_modelRolesUpdater) {
 364         return;
 365     }
 366
 367     m_modelRolesUpdater->setIconSize(availableIconSize());
 368
 369     // Update the visible index range (which has most likely changed after the
 370     // icon size change) before unpausing m_modelRolesUpdater.
 371     const int index = firstVisibleIndex();
 372     const int count = lastVisibleIndex() - index + 1;
 373     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 374
 375     m_modelRolesUpdater->setPaused(isTransactionActive());
 376 }
 377
 378 void KFileItemListView::applyRolesToModel()
 379 {
 380     if (!model()) {
 381         return;
 382     }
 383
 384     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 385     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 386
 387     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 388     // Add all roles that are mandatory for having a working KFileItemListView:
 389     QSet<QByteArray> roles = visibleRoles().toSet();
 390     roles.insert("iconPixmap");
 391     roles.insert("iconName");
 392     roles.insert("text");
 393     roles.insert("isDir");
 394     roles.insert("isLink");
 395     if (supportsItemExpanding()) {
 396         roles.insert("isExpanded");
 397         roles.insert("isExpandable");
 398         roles.insert("expandedParentsCount");
 399     }
 400
 401     // Assure that the role that is used for sorting will be determined
 402     roles.insert(fileItemModel->sortRole());
 403
 404     fileItemModel->setRoles(roles);
 405     m_modelRolesUpdater->setRoles(roles);
 406 }
 407
 408 QSize KFileItemListView::availableIconSize() const
 409 {
 410     const KItemListStyleOption& option = styleOption();
 411     const int iconSize = option.iconSize;
 412     if (itemLayout() == IconsLayout) {
 413         const int maxIconWidth = itemSize().width() - 2 * option.padding;
 414         return QSize(maxIconWidth, iconSize);
 415     }
 416
 417     return QSize(iconSize, iconSize);
 418 }
 419