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