src/views/tooltips/tooltipmanager.cpp

   1 /*******************************************************************************
   2  *   Copyright (C) 2008 by Konstantin Heil <konst.heil@stud.uni-heidelberg.de> *
   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 "tooltipmanager.h"
  21
  22 #include "filemetadatatooltip.h"
  23 #include <KIcon>
  24 #include <KIO/PreviewJob>
  25 #include <KSharedConfig>
  26
  27 #include <QApplication>
  28 #include <QDesktopWidget>
  29 #include <QScrollArea>
  30 #include <QScrollBar>
  31 #include <QTimer>
  32
  33 #include <views/dolphinmodel.h>
  34 #include <views/dolphinsortfilterproxymodel.h>
  35
  36 ToolTipManager::ToolTipManager(QAbstractItemView* parent,
  37                                DolphinSortFilterProxyModel* model) :
  38     QObject(parent),
  39     m_view(parent),
  40     m_dolphinModel(0),
  41     m_proxyModel(model),
  42     m_showToolTipTimer(0),
  43     m_contentRetrievalTimer(0),
  44     m_fileMetaDataToolTip(0),
  45     m_toolTipRequested(false),
  46     m_metaDataRequested(false),
  47     m_appliedWaitCursor(false),
  48     m_item(),
  49     m_itemRect()
  50 {
  51     m_dolphinModel = static_cast<DolphinModel*>(m_proxyModel->sourceModel());
  52     connect(parent, SIGNAL(entered(const QModelIndex&)),
  53             this, SLOT(requestToolTip(const QModelIndex&)));
  54     connect(parent, SIGNAL(viewportEntered()),
  55             this, SLOT(hideToolTip()));
  56
  57     // Initialize timers
  58     m_showToolTipTimer = new QTimer(this);
  59     m_showToolTipTimer->setSingleShot(true);
  60     m_showToolTipTimer->setInterval(500);
  61     connect(m_showToolTipTimer, SIGNAL(timeout()), this, SLOT(showToolTip()));
  62
  63     m_contentRetrievalTimer = new QTimer(this);
  64     m_contentRetrievalTimer->setSingleShot(true);
  65     m_contentRetrievalTimer->setInterval(200);
  66     connect(m_contentRetrievalTimer, SIGNAL(timeout()), this, SLOT(startContentRetrieval()));
  67
  68     Q_ASSERT(m_contentRetrievalTimer->interval() < m_showToolTipTimer->interval());
  69
  70     // When the mousewheel is used, the items don't get a hovered indication
  71     // (Qt-issue #200665). To assure that the tooltip still gets hidden,
  72     // the scrollbars are observed.
  73     connect(parent->horizontalScrollBar(), SIGNAL(valueChanged(int)),
  74             this, SLOT(hideToolTip()));
  75     connect(parent->verticalScrollBar(), SIGNAL(valueChanged(int)),
  76             this, SLOT(hideToolTip()));
  77
  78     Q_ASSERT(m_view);
  79     m_view->viewport()->installEventFilter(this);
  80     m_view->installEventFilter(this);
  81 }
  82
  83 ToolTipManager::~ToolTipManager()
  84 {
  85 }
  86
  87 void ToolTipManager::hideToolTip()
  88 {
  89     if (m_appliedWaitCursor) {
  90         QApplication::restoreOverrideCursor();
  91         m_appliedWaitCursor = false;
  92     }
  93
  94     m_toolTipRequested = false;
  95     m_metaDataRequested = false;
  96     m_showToolTipTimer->stop();
  97     m_contentRetrievalTimer->stop();
  98
  99     delete m_fileMetaDataToolTip;
 100     m_fileMetaDataToolTip = 0;}
 101
 102
 103 bool ToolTipManager::eventFilter(QObject* watched, QEvent* event)
 104 {
 105     if (watched == m_view->viewport()) {
 106         switch (event->type()) {
 107         case QEvent::Leave:
 108         case QEvent::MouseButtonPress:
 109             hideToolTip();
 110             break;
 111         default:
 112             break;
 113         }
 114     } else if ((watched == m_view) && (event->type() == QEvent::KeyPress)) {
 115         hideToolTip();
 116     }
 117
 118     return QObject::eventFilter(watched, event);
 119 }
 120
 121 void ToolTipManager::requestToolTip(const QModelIndex& index)
 122 {
 123     hideToolTip();
 124
 125     // Only request a tooltip for the name column and when no selection or
 126     // drag & drop operation is done (indicated by the left mouse button)
 127     if ((index.column() == DolphinModel::Name) && !(QApplication::mouseButtons() & Qt::LeftButton)) {
 128         m_itemRect = m_view->visualRect(index);
 129         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 130         m_itemRect.moveTo(pos);
 131
 132         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 133         m_item = m_dolphinModel->itemForIndex(dirIndex);
 134
 135         // Only start the retrieving of the content, when the mouse has been over this
 136         // item for 200 milliseconds. This prevents a lot of useless preview jobs and
 137         // meta data retrieval, when passing rapidly over a lot of items.
 138         Q_ASSERT(!m_fileMetaDataToolTip);
 139         m_fileMetaDataToolTip = new FileMetaDataToolTip(m_view);
 140         connect(m_fileMetaDataToolTip, SIGNAL(metaDataRequestFinished(KFileItemList)),
 141                 this, SLOT(slotMetaDataRequestFinished()));
 142
 143         m_contentRetrievalTimer->start();
 144         m_showToolTipTimer->start();
 145         m_toolTipRequested = true;
 146         Q_ASSERT(!m_metaDataRequested);
 147     }
 148 }
 149
 150 void ToolTipManager::startContentRetrieval()
 151 {
 152     if (!m_toolTipRequested) {
 153         return;
 154     }
 155
 156     m_fileMetaDataToolTip->setName(m_item.text());
 157
 158     // Request the retrieval of meta-data. The slot
 159     // slotMetaDataRequestFinished() is invoked after the
 160     // meta-data have been received.
 161     m_metaDataRequested = true;
 162     m_fileMetaDataToolTip->setItems(KFileItemList() << m_item);
 163
 164     // Request a preview of the item
 165     m_fileMetaDataToolTip->setPreview(QPixmap());
 166
 167     KIO::PreviewJob* job = KIO::filePreview(KFileItemList() << m_item, QSize(256, 256));
 168
 169     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 170             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 171     connect(job, SIGNAL(failed(const KFileItem&)),
 172             this, SLOT(previewFailed()));
 173 }
 174
 175
 176 void ToolTipManager::setPreviewPix(const KFileItem& item,
 177                                    const QPixmap& pixmap)
 178 {
 179     if (!m_toolTipRequested || (m_item.url() != item.url())) {
 180         // No tooltip is requested anymore or an old preview has been received
 181         return;
 182     }
 183
 184     if (pixmap.isNull()) {
 185         previewFailed();
 186     } else {
 187         m_fileMetaDataToolTip->setPreview(pixmap);
 188         if (!m_showToolTipTimer->isActive()) {
 189             showToolTip();
 190         }
 191     }
 192 }
 193
 194 void ToolTipManager::previewFailed()
 195 {
 196     if (!m_toolTipRequested) {
 197         return;
 198     }
 199
 200     const QPixmap pixmap = KIcon(m_item.iconName()).pixmap(128, 128);
 201     m_fileMetaDataToolTip->setPreview(pixmap);
 202     if (!m_showToolTipTimer->isActive()) {
 203         showToolTip();
 204     }
 205 }
 206
 207 void ToolTipManager::slotMetaDataRequestFinished()
 208 {
 209     if (!m_toolTipRequested) {
 210         return;
 211     }
 212
 213     m_metaDataRequested = false;
 214     if (!m_showToolTipTimer->isActive()) {
 215         showToolTip();
 216     }
 217 }
 218
 219 void ToolTipManager::showToolTip()
 220 {
 221     Q_ASSERT(m_toolTipRequested);
 222     if (m_appliedWaitCursor) {
 223         QApplication::restoreOverrideCursor();
 224         m_appliedWaitCursor = false;
 225     }
 226
 227     if (QApplication::mouseButtons() & Qt::LeftButton) {
 228         return;
 229     }
 230
 231     if (m_fileMetaDataToolTip->preview().isNull() || m_metaDataRequested) {
 232         Q_ASSERT(!m_appliedWaitCursor);
 233         QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
 234         m_appliedWaitCursor = true;
 235         return;
 236     }
 237
 238     const QRect screen = QApplication::desktop()->screenGeometry(QCursor::pos());
 239
 240     // Restrict tooltip size to current screen size when needed.
 241     // Because layout controlling widget doesn't respect widget's maximumSize property
 242     // (correct me if I'm wrong), we need to let layout do its work, then manually change
 243     // geometry if resulting widget doesn't fit the screen.
 244
 245     // Step #1 - make sizeHint return calculated tooltip size
 246     m_fileMetaDataToolTip->layout()->setSizeConstraint(QLayout::SetFixedSize);
 247     m_fileMetaDataToolTip->adjustSize();
 248     QSize size = m_fileMetaDataToolTip->sizeHint();
 249
 250     // Step #2 - correct tooltip size when needed
 251     if (size.width() > screen.width()) {
 252         size.setWidth(screen.width());
 253     }
 254     if (size.height() > screen.height()) {
 255         size.setHeight(screen.height());
 256     }
 257
 258     // m_itemRect defines the area of the item, where the tooltip should be
 259     // shown. Per default the tooltip is shown in the bottom right corner.
 260     // It must be assured that:
 261     // - the content is fully visible
 262     // - the content is not drawn inside m_itemRect
 263     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= screen.left());
 264     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= screen.right());
 265     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= screen.top());
 266     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= screen.bottom());
 267     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 268         return;
 269     }
 270
 271     int x, y;
 272     if (hasRoomBelow || hasRoomAbove) {
 273         x = QCursor::pos().x() + 16; // TODO: use mouse pointer width instead of the magic value of 16
 274         if (x + size.width() >= screen.right()) {
 275             x = screen.right() - size.width() + 1;
 276         }
 277         if (hasRoomBelow) {
 278             y = m_itemRect.bottom() + 1;
 279         } else {
 280             y = m_itemRect.top() - size.height();
 281         }
 282     } else {
 283         Q_ASSERT(hasRoomToLeft || hasRoomToRight);
 284         if (hasRoomToRight) {
 285             x = m_itemRect.right() + 1;
 286         } else {
 287             x = m_itemRect.left() - size.width();
 288         }
 289         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 290         // been adjusted, so that no overlapping with m_itemRect occurs.
 291         y = screen.bottom() - size.height() + 1;
 292     }
 293
 294     // Step #3 - Alter tooltip geometry
 295     m_fileMetaDataToolTip->setFixedSize(size);
 296     m_fileMetaDataToolTip->layout()->setSizeConstraint(QLayout::SetNoConstraint);
 297     m_fileMetaDataToolTip->setGeometry(x, y, size.width(), size.height());
 298     m_fileMetaDataToolTip->show();
 299
 300     m_toolTipRequested = false;
 301 }
 302
 303 #include "tooltipmanager.moc"