src/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 "dolphinmodel.h"
  23 #include "dolphinsortfilterproxymodel.h"
  24
  25 #include <kicon.h>
  26 #include <kio/previewjob.h>
  27 #include <kseparator.h>
  28
  29 #include "panels/information/kmetadatawidget.h"
  30 #include "tooltips/ktooltip.h"
  31
  32 #include <QApplication>
  33 #include <QDesktopWidget>
  34 #include <QHBoxLayout>
  35 #include <QLabel>
  36 #include <QScrollArea>
  37 #include <QScrollBar>
  38 #include <QTimer>
  39 #include <QVBoxLayout>
  40
  41 ToolTipManager::ToolTipManager(QAbstractItemView* parent,
  42                                DolphinSortFilterProxyModel* model) :
  43     QObject(parent),
  44     m_view(parent),
  45     m_dolphinModel(0),
  46     m_proxyModel(model),
  47     m_timer(0),
  48     m_previewTimer(0),
  49     m_waitOnPreviewTimer(0),
  50     m_item(),
  51     m_itemRect(),
  52     m_generatingPreview(false),
  53     m_hasDefaultIcon(false),
  54     m_previewPixmap()
  55 {
  56     m_dolphinModel = static_cast<DolphinModel*>(m_proxyModel->sourceModel());
  57     connect(parent, SIGNAL(entered(const QModelIndex&)),
  58             this, SLOT(requestToolTip(const QModelIndex&)));
  59     connect(parent, SIGNAL(viewportEntered()),
  60             this, SLOT(hideToolTip()));
  61
  62     m_timer = new QTimer(this);
  63     m_timer->setSingleShot(true);
  64     connect(m_timer, SIGNAL(timeout()),
  65             this, SLOT(prepareToolTip()));
  66
  67     m_previewTimer = new QTimer(this);
  68     m_previewTimer->setSingleShot(true);
  69     connect(m_previewTimer, SIGNAL(timeout()),
  70             this, SLOT(startPreviewJob()));
  71
  72     m_waitOnPreviewTimer = new QTimer(this);
  73     m_waitOnPreviewTimer->setSingleShot(true);
  74     connect(m_waitOnPreviewTimer, SIGNAL(timeout()),
  75             this, SLOT(prepareToolTip()));
  76
  77     // When the mousewheel is used, the items don't get a hovered indication
  78     // (Qt-issue #200665). To assure that the tooltip still gets hidden,
  79     // the scrollbars are observed.
  80     connect(parent->horizontalScrollBar(), SIGNAL(valueChanged(int)),
  81             this, SLOT(hideTip()));
  82     connect(parent->verticalScrollBar(), SIGNAL(valueChanged(int)),
  83             this, SLOT(hideTip()));
  84
  85     m_view->viewport()->installEventFilter(this);
  86     m_view->installEventFilter(this);
  87 }
  88
  89 ToolTipManager::~ToolTipManager()
  90 {
  91 }
  92
  93 void ToolTipManager::hideTip()
  94 {
  95     hideToolTip();
  96 }
  97
  98 bool ToolTipManager::eventFilter(QObject* watched, QEvent* event)
  99 {
 100     if (watched == m_view->viewport()) {
 101         switch (event->type()) {
 102         case QEvent::Leave:
 103         case QEvent::MouseButtonPress:
 104             hideToolTip();
 105             break;
 106         default:
 107             break;
 108         }
 109     } else if ((watched == m_view) && (event->type() == QEvent::KeyPress)) {
 110         hideToolTip();
 111     }
 112
 113     return QObject::eventFilter(watched, event);
 114 }
 115
 116 void ToolTipManager::requestToolTip(const QModelIndex& index)
 117 {
 118     // only request a tooltip for the name column and when no selection or
 119     // drag & drop operation is done (indicated by the left mouse button)
 120     if ((index.column() == DolphinModel::Name) && !(QApplication::mouseButtons() & Qt::LeftButton)) {
 121         m_waitOnPreviewTimer->stop();
 122         KToolTip::hideTip();
 123
 124         m_itemRect = m_view->visualRect(index);
 125         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 126         m_itemRect.moveTo(pos);
 127
 128         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 129         m_item = m_dolphinModel->itemForIndex(dirIndex);
 130
 131         // only start the previewJob when the mouse has been over this item for 200 milliseconds,
 132         // this prevents a lot of useless preview jobs when passing rapidly over a lot of items
 133         m_previewTimer->start(200);
 134         m_previewPixmap = QPixmap();
 135         m_hasDefaultIcon = false;
 136
 137         m_timer->start(500);
 138     } else {
 139         hideToolTip();
 140     }
 141 }
 142
 143 void ToolTipManager::hideToolTip()
 144 {
 145     m_timer->stop();
 146     m_previewTimer->stop();
 147     m_waitOnPreviewTimer->stop();
 148     KToolTip::hideTip();
 149 }
 150
 151 void ToolTipManager::prepareToolTip()
 152 {
 153     if (m_generatingPreview) {
 154         m_waitOnPreviewTimer->start(250);
 155     }
 156
 157     if (!m_previewPixmap.isNull()) {
 158         showToolTip(m_previewPixmap);
 159     } else if (!m_hasDefaultIcon) {
 160         const QPixmap image(KIcon(m_item.iconName()).pixmap(128, 128));
 161         showToolTip(image);
 162         m_hasDefaultIcon = true;
 163     }
 164 }
 165
 166 void ToolTipManager::startPreviewJob()
 167 {
 168     m_generatingPreview = true;
 169     KIO::PreviewJob* job = KIO::filePreview(KFileItemList() << m_item, 256, 256);
 170
 171     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 172             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 173     connect(job, SIGNAL(failed(const KFileItem&)),
 174             this, SLOT(previewFailed()));
 175 }
 176
 177
 178 void ToolTipManager::setPreviewPix(const KFileItem& item,
 179                                    const QPixmap& pixmap)
 180 {
 181     if ((m_item.url() != item.url()) || pixmap.isNull()) {
 182         // an old preview or an invalid preview has been received
 183         previewFailed();
 184     } else {
 185         m_previewPixmap = pixmap;
 186         m_generatingPreview = false;
 187     }
 188 }
 189
 190 void ToolTipManager::previewFailed()
 191 {
 192     m_generatingPreview = false;
 193 }
 194
 195
 196 void ToolTipManager::showToolTip(const QPixmap& pixmap)
 197 {
 198     if (QApplication::mouseButtons() & Qt::LeftButton) {
 199         return;
 200     }
 201
 202     QWidget* tip = createTipContent(pixmap);
 203
 204     // calculate the x- and y-position of the tooltip
 205     const QSize size = tip->sizeHint();
 206     const QRect desktop = QApplication::desktop()->screenGeometry(m_itemRect.bottomRight());
 207
 208     // m_itemRect defines the area of the item, where the tooltip should be
 209     // shown. Per default the tooltip is shown in the bottom right corner.
 210     // If the tooltip content exceeds the desktop borders, it must be assured that:
 211     // - the content is fully visible
 212     // - the content is not drawn inside m_itemRect
 213     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= desktop.left());
 214     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= desktop.right());
 215     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= desktop.top());
 216     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= desktop.bottom());
 217     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 218         delete tip;
 219         tip = 0;
 220         return;
 221     }
 222
 223     int x = 0;
 224     int y = 0;
 225     if (hasRoomBelow || hasRoomAbove) {
 226         x = QCursor::pos().x() + 16; // TODO: use mouse pointer width instead of the magic value of 16
 227         if (x + size.width() >= desktop.right()) {
 228             x = desktop.right() - size.width();
 229         }
 230         y = hasRoomBelow ? m_itemRect.bottom() : m_itemRect.top() - size.height();
 231     } else {
 232         Q_ASSERT(hasRoomToLeft || hasRoomToRight);
 233         x = hasRoomToRight ? m_itemRect.right() : m_itemRect.left() - size.width();
 234
 235         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 236         // been adjusted, so that no overlapping with m_itemRect occurs.
 237         y = desktop.bottom() - size.height();
 238     }
 239
 240     // the ownership of tip is transferred to KToolTip
 241     KToolTip::showTip(QPoint(x, y), tip);
 242 }
 243
 244 QWidget* ToolTipManager::createTipContent(const QPixmap& pixmap) const
 245 {
 246     QWidget* tipContent = new QWidget();
 247
 248     // add pixmap
 249     QLabel* pixmapLabel = new QLabel(tipContent);
 250     pixmapLabel->setPixmap(pixmap);
 251     pixmapLabel->setFixedSize(pixmap.size());
 252
 253     // add item name
 254     QLabel* nameLabel = new QLabel(tipContent);
 255     nameLabel->setText(m_item.name());
 256     nameLabel->setWordWrap(true);
 257     QFont font = nameLabel->font();
 258     font.setBold(true);
 259     nameLabel->setFont(font);
 260     nameLabel->setAlignment(Qt::AlignHCenter);
 261     nameLabel->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
 262
 263     // add meta data
 264     KMetaDataWidget* metaDataWidget = new KMetaDataWidget(tipContent);
 265     metaDataWidget->setForegroundRole(QPalette::ToolTipText);
 266     metaDataWidget->setItem(m_item);
 267     metaDataWidget->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
 268     metaDataWidget->setReadOnly(true);
 269
 270     // the stretchwidget allows the metadata widget to be top aligned and fills
 271     // the remaining vertical space
 272     QWidget* stretchWidget = new QWidget(tipContent);
 273     stretchWidget->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::MinimumExpanding);
 274
 275     QWidget* textContainer = new QWidget(tipContent);
 276     QVBoxLayout* textLayout = new QVBoxLayout(textContainer);
 277     textLayout->addWidget(nameLabel);
 278     textLayout->addWidget(new KSeparator());
 279     textLayout->addWidget(metaDataWidget);
 280     textLayout->addWidget(stretchWidget);
 281
 282     QHBoxLayout* tipLayout = new QHBoxLayout(tipContent);
 283     tipLayout->setMargin(0);
 284     tipLayout->addWidget(pixmapLabel);
 285     tipLayout->addWidget(textContainer);
 286
 287     return tipContent;
 288 }
 289
 290 #include "tooltipmanager.moc"