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 <QDebug>
  28 #include <QIcon>
  29 #include <KIconLoader>
  30
  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 immediatetly, 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     // chaning the zoom level.
  46     const int LongInterval = 300;
  47 }
  48
  49 KFileItemListView::KFileItemListView(QGraphicsWidget* parent) :
  50     KStandardItemListView(parent),
  51     m_modelRolesUpdater(0),
  52     m_updateVisibleIndexRangeTimer(0),
  53     m_updateIconSizeTimer(0)
  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(QList<QByteArray>() << "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     // Draw the selected items into the grid cells.
 159     QPixmap dragPixmap(xCount * size + xCount, yCount * size + yCount);
 160     dragPixmap.fill(Qt::transparent);
 161
 162     QPainter painter(&dragPixmap);
 163     int x = 0;
 164     int y = 0;
 165
 166     foreach (int index, indexes) {
 167         QPixmap pixmap = model()->data(index).value("iconPixmap").value<QPixmap>();
 168         if (pixmap.isNull()) {
 169             QIcon icon = QIcon::fromTheme(model()->data(index).value("iconName").toString());
 170             pixmap = icon.pixmap(size, size);
 171         } else {
 172             KPixmapModifier::scale(pixmap, QSize(size, size));
 173         }
 174
 175         painter.drawPixmap(x, y, pixmap);
 176
 177         x += size + 1;
 178         if (x >= dragPixmap.width()) {
 179             x = 0;
 180             y += size + 1;
 181         }
 182
 183         if (y >= dragPixmap.height()) {
 184             break;
 185         }
 186     }
 187
 188     return dragPixmap;
 189 }
 190
 191 KItemListWidgetCreatorBase* KFileItemListView::defaultWidgetCreator() const
 192 {
 193     return new KItemListWidgetCreator<KFileItemListWidget>();
 194 }
 195
 196 void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
 197 {
 198     KStandardItemListView::initializeItemListWidget(item);
 199
 200     // Make sure that the item has an icon.
 201     QHash<QByteArray, QVariant> data = item->data();
 202     if (!data.contains("iconName") && data["iconPixmap"].value<QPixmap>().isNull()) {
 203         Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 204         KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 205
 206         const KFileItem fileItem = fileItemModel->fileItem(item->index());
 207         data.insert("iconName", fileItem.iconName());
 208         item->setData(data, QSet<QByteArray>() << "iconName");
 209     }
 210 }
 211
 212 void KFileItemListView::onPreviewsShownChanged(bool shown)
 213 {
 214     Q_UNUSED(shown);
 215 }
 216
 217 void KFileItemListView::onItemLayoutChanged(ItemLayout current, ItemLayout previous)
 218 {
 219     KStandardItemListView::onItemLayoutChanged(current, previous);
 220     triggerVisibleIndexRangeUpdate();
 221 }
 222
 223 void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 224 {
 225     Q_ASSERT(qobject_cast<KFileItemModel*>(current));
 226     KStandardItemListView::onModelChanged(current, previous);
 227
 228     delete m_modelRolesUpdater;
 229     m_modelRolesUpdater = 0;
 230
 231     if (current) {
 232         m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
 233         m_modelRolesUpdater->setIconSize(availableIconSize());
 234
 235         applyRolesToModel();
 236     }
 237 }
 238
 239 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 240 {
 241     KStandardItemListView::onScrollOrientationChanged(current, previous);
 242     triggerVisibleIndexRangeUpdate();
 243 }
 244
 245 void KFileItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 246 {
 247     Q_UNUSED(current);
 248     Q_UNUSED(previous);
 249     triggerVisibleIndexRangeUpdate();
 250 }
 251
 252 void KFileItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 253 {
 254     KStandardItemListView::onScrollOffsetChanged(current, previous);
 255     triggerVisibleIndexRangeUpdate();
 256 }
 257
 258 void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 259 {
 260     KStandardItemListView::onVisibleRolesChanged(current, previous);
 261     applyRolesToModel();
 262 }
 263
 264 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 265 {
 266     KStandardItemListView::onStyleOptionChanged(current, previous);
 267     triggerIconSizeUpdate();
 268 }
 269
 270 void KFileItemListView::onSupportsItemExpandingChanged(bool supportsExpanding)
 271 {
 272     applyRolesToModel();
 273     KStandardItemListView::onSupportsItemExpandingChanged(supportsExpanding);
 274     triggerVisibleIndexRangeUpdate();
 275 }
 276
 277 void KFileItemListView::onTransactionBegin()
 278 {
 279     if (m_modelRolesUpdater) {
 280         m_modelRolesUpdater->setPaused(true);
 281     }
 282 }
 283
 284 void KFileItemListView::onTransactionEnd()
 285 {
 286     if (!m_modelRolesUpdater) {
 287         return;
 288     }
 289
 290     // Only unpause the model-roles-updater if no timer is active. If one
 291     // timer is still active the model-roles-updater will be unpaused later as
 292     // soon as the timer has been exceeded.
 293     const bool timerActive = m_updateVisibleIndexRangeTimer->isActive() ||
 294                              m_updateIconSizeTimer->isActive();
 295     if (!timerActive) {
 296         m_modelRolesUpdater->setPaused(false);
 297     }
 298 }
 299
 300 void KFileItemListView::resizeEvent(QGraphicsSceneResizeEvent* event)
 301 {
 302     KStandardItemListView::resizeEvent(event);
 303     triggerVisibleIndexRangeUpdate();
 304 }
 305
 306 void KFileItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
 307 {
 308     KStandardItemListView::slotItemsRemoved(itemRanges);
 309 }
 310
 311 void KFileItemListView::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
 312 {
 313     const QByteArray sortRole = model()->sortRole();
 314     if (!visibleRoles().contains(sortRole)) {
 315         applyRolesToModel();
 316     }
 317
 318     KStandardItemListView::slotSortRoleChanged(current, previous);
 319 }
 320
 321 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 322 {
 323     if (!model()) {
 324         return;
 325     }
 326     m_modelRolesUpdater->setPaused(true);
 327
 328     // If the icon size has been changed recently, wait until
 329     // m_updateIconSizeTimer expires.
 330     if (!m_updateIconSizeTimer->isActive()) {
 331         m_updateVisibleIndexRangeTimer->start();
 332     }
 333 }
 334
 335 void KFileItemListView::updateVisibleIndexRange()
 336 {
 337     if (!m_modelRolesUpdater) {
 338         return;
 339     }
 340
 341     const int index = firstVisibleIndex();
 342     const int count = lastVisibleIndex() - index + 1;
 343     m_modelRolesUpdater->setMaximumVisibleItems(maximumVisibleItems());
 344     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 345     m_modelRolesUpdater->setPaused(isTransactionActive());
 346 }
 347
 348 void KFileItemListView::triggerIconSizeUpdate()
 349 {
 350     if (!model()) {
 351         return;
 352     }
 353     m_modelRolesUpdater->setPaused(true);
 354     m_updateIconSizeTimer->start();
 355
 356     // The visible index range will be updated when m_updateIconSizeTimer expires.
 357     // Stop m_updateVisibleIndexRangeTimer to prevent an expensive re-generation
 358     // of all previews (note that the user might change the icon size again soon).
 359     m_updateVisibleIndexRangeTimer->stop();
 360 }
 361
 362 void KFileItemListView::updateIconSize()
 363 {
 364     if (!m_modelRolesUpdater) {
 365         return;
 366     }
 367
 368     m_modelRolesUpdater->setIconSize(availableIconSize());
 369
 370     // Update the visible index range (which has most likely changed after the
 371     // icon size change) before unpausing m_modelRolesUpdater.
 372     const int index = firstVisibleIndex();
 373     const int count = lastVisibleIndex() - index + 1;
 374     m_modelRolesUpdater->setVisibleIndexRange(index, count);
 375
 376     m_modelRolesUpdater->setPaused(isTransactionActive());
 377 }
 378
 379 void KFileItemListView::applyRolesToModel()
 380 {
 381     if (!model()) {
 382         return;
 383     }
 384
 385     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
 386     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 387
 388     // KFileItemModel does not distinct between "visible" and "invisible" roles.
 389     // Add all roles that are mandatory for having a working KFileItemListView:
 390     QSet<QByteArray> roles = visibleRoles().toSet();
 391     roles.insert("iconPixmap");
 392     roles.insert("iconName");
 393     roles.insert("text");
 394     roles.insert("isDir");
 395     roles.insert("isLink");
 396     if (supportsItemExpanding()) {
 397         roles.insert("isExpanded");
 398         roles.insert("isExpandable");
 399         roles.insert("expandedParentsCount");
 400     }
 401
 402     // Assure that the role that is used for sorting will be determined
 403     roles.insert(fileItemModel->sortRole());
 404
 405     fileItemModel->setRoles(roles);
 406     m_modelRolesUpdater->setRoles(roles);
 407 }
 408
 409 QSize KFileItemListView::availableIconSize() const
 410 {
 411     const KItemListStyleOption& option = styleOption();
 412     const int iconSize = option.iconSize;
 413     if (itemLayout() == IconsLayout) {
 414         const int maxIconWidth = itemSize().width() - 2 * option.padding;
 415         return QSize(maxIconWidth, iconSize);
 416     }
 417
 418     return QSize(iconSize, iconSize);
 419 }
 420