apps/dolphin/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 "dolphintooltip.h"
  23 #include "dolphinmodel.h"
  24 #include "dolphinsortfilterproxymodel.h"
  25
  26 #include <kicon.h>
  27 #include <tooltips/ktooltip.h>
  28 #include <kio/previewjob.h>
  29
  30 #include <QApplication>
  31 #include <QDesktopWidget>
  32 #include <QScrollBar>
  33 #include <QTimer>
  34 #include <QToolTip>
  35
  36 const int ICON_WIDTH = 128;
  37 const int ICON_HEIGHT = 128;
  38 const int PREVIEW_DELAY = 250;
  39
  40 K_GLOBAL_STATIC(DolphinBalloonTooltipDelegate, g_delegate)
  41
  42 ToolTipManager::ToolTipManager(QAbstractItemView* parent,
  43                                DolphinSortFilterProxyModel* model) :
  44     QObject(parent),
  45     m_view(parent),
  46     m_dolphinModel(0),
  47     m_proxyModel(model),
  48     m_timer(0),
  49     m_previewTimer(0),
  50     m_waitOnPreviewTimer(0),
  51     m_item(),
  52     m_itemRect(),
  53     m_preview(false),
  54     m_generatingPreview(false),
  55     m_previewIsLate(false),
  56     m_previewPass(0),
  57     m_emptyRenderedKToolTipItem(0),
  58     m_pix()
  59 {
  60     KToolTip::setToolTipDelegate(g_delegate);
  61
  62     m_dolphinModel = static_cast<DolphinModel*>(m_proxyModel->sourceModel());
  63     connect(parent, SIGNAL(entered(const QModelIndex&)),
  64             this, SLOT(requestToolTip(const QModelIndex&)));
  65     connect(parent, SIGNAL(viewportEntered()),
  66             this, SLOT(hideToolTip()));
  67
  68     m_timer = new QTimer(this);
  69     m_timer->setSingleShot(true);
  70     connect(m_timer, SIGNAL(timeout()),
  71             this, SLOT(prepareToolTip()));
  72
  73     m_previewTimer = new QTimer(this);
  74     m_previewTimer->setSingleShot(true);
  75     connect(m_previewTimer, SIGNAL(timeout()),
  76             this, SLOT(startPreviewJob()));
  77
  78     m_waitOnPreviewTimer = new QTimer(this);
  79     m_waitOnPreviewTimer->setSingleShot(true);
  80     connect(m_waitOnPreviewTimer, SIGNAL(timeout()),
  81             this, SLOT(prepareToolTip()));
  82
  83     // When the mousewheel is used, the items don't get a hovered indication
  84     // (Qt-issue #200665). To assure that the tooltip still gets hidden,
  85     // the scrollbars are observed.
  86     connect(parent->horizontalScrollBar(), SIGNAL(valueChanged(int)),
  87             this, SLOT(hideTip()));
  88     connect(parent->verticalScrollBar(), SIGNAL(valueChanged(int)),
  89             this, SLOT(hideTip()));
  90
  91     m_view->viewport()->installEventFilter(this);
  92 }
  93
  94 ToolTipManager::~ToolTipManager()
  95 {
  96 }
  97
  98 void ToolTipManager::hideTip()
  99 {
 100     hideToolTip();
 101 }
 102
 103 bool ToolTipManager::eventFilter(QObject* watched, QEvent* event)
 104 {
 105     if ((watched == m_view->viewport()) && (event->type() == QEvent::Leave)) {
 106         hideToolTip();
 107     }
 108
 109     return QObject::eventFilter(watched, event);
 110 }
 111
 112 void ToolTipManager::requestToolTip(const QModelIndex& index)
 113 {
 114     // only request a tooltip for the name column and when no selection or
 115     // drag & drop operation is done (indicated by the left mouse button)
 116     if ((index.column() == DolphinModel::Name) && !(QApplication::mouseButtons() & Qt::LeftButton)) {
 117         m_waitOnPreviewTimer->stop();
 118         KToolTip::hideTip();
 119
 120         m_itemRect = m_view->visualRect(index);
 121         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 122         m_itemRect.moveTo(pos);
 123
 124         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 125         m_item = m_dolphinModel->itemForIndex(dirIndex);
 126
 127         // only start the previewJob when the mouse has been over this item for 200 milliseconds,
 128         // this prevents a lot of useless preview jobs when passing rapidly over a lot of items
 129         m_previewTimer->start(200);
 130         m_preview = false;
 131         m_previewIsLate = false;
 132         m_previewPass = 0;
 133
 134         m_timer->start(500);
 135     } else {
 136         hideToolTip();
 137     }
 138 }
 139
 140 void ToolTipManager::hideToolTip()
 141 {
 142     m_timer->stop();
 143     m_previewTimer->stop();
 144     m_waitOnPreviewTimer->stop();
 145     m_previewIsLate = false;
 146     KToolTip::hideTip();
 147 }
 148
 149 void ToolTipManager::prepareToolTip()
 150 {
 151     if (m_generatingPreview) {
 152         if (m_previewPass == 1) {
 153             // We waited 250msec and the preview is still not finished,
 154             // so show the toolTip with a transparent image of maximal width.
 155             // When the preview finishes, m_previewIsLate will cause
 156             // a direct update of the tooltip, via m_emptyRenderedKToolTipItem.
 157             QPixmap paddedImage(QSize(PREVIEW_WIDTH, 32));
 158             m_previewIsLate = true;
 159             paddedImage.fill(Qt::transparent);
 160             KToolTipItem* toolTip = new KToolTipItem(paddedImage, m_item.getToolTipText());
 161             m_emptyRenderedKToolTipItem = toolTip; // make toolTip accessible everywhere
 162             showToolTip(toolTip);
 163         }
 164
 165         ++m_previewPass;
 166         m_waitOnPreviewTimer->start(250);
 167     } else {
 168         // The preview generation has finished, find out under which circumstances.
 169         if (m_preview && m_previewIsLate) {
 170             // We got a preview, but it is late, the tooltip has already been shown.
 171             // So update the tooltip directly.
 172             if (m_emptyRenderedKToolTipItem != 0) {
 173                 m_emptyRenderedKToolTipItem->setData(Qt::DecorationRole, KIcon(m_pix));
 174             }
 175             return;
 176         }
 177
 178         KIcon icon;
 179         if (m_preview) {
 180             // We got a preview.
 181             icon = KIcon(m_pix);
 182         } else {
 183             // No preview, so use an icon.
 184             // Force a 128x128 icon, a 256x256 one is far too big.
 185             icon = KIcon(KIcon(m_item.iconName()).pixmap(ICON_WIDTH, ICON_HEIGHT));
 186         }
 187
 188         KToolTipItem* toolTip = new KToolTipItem(icon, m_item.getToolTipText());
 189         showToolTip(toolTip);
 190     }
 191 }
 192
 193 void ToolTipManager::showToolTip(KToolTipItem* tip)
 194 {
 195     if (QApplication::mouseButtons() & Qt::LeftButton) {
 196         delete tip;
 197         tip = 0;
 198         // m_emptyRenderedKToolTipItem is an alias for tip.
 199         m_emptyRenderedKToolTipItem = 0;
 200         return;
 201     }
 202
 203     KStyleOptionToolTip option;
 204     // TODO: get option content from KToolTip or add KToolTip::sizeHint() method
 205     option.direction      = QApplication::layoutDirection();
 206     option.fontMetrics    = QFontMetrics(QToolTip::font());
 207     option.activeCorner   = KStyleOptionToolTip::TopLeftCorner;
 208     option.palette        = QToolTip::palette();
 209     option.font           = QToolTip::font();
 210     option.rect           = QRect();
 211     option.state          = QStyle::State_None;
 212     option.decorationSize = QSize(32, 32);
 213
 214     QSize size;
 215     if (m_previewIsLate) {
 216         QPixmap paddedImage(QSize(PREVIEW_WIDTH, PREVIEW_HEIGHT));
 217         KToolTipItem* maxiTip = new KToolTipItem(paddedImage, m_item.getToolTipText());
 218         size = g_delegate->sizeHint(&option, maxiTip);
 219         delete maxiTip;
 220         maxiTip = 0;
 221     }
 222     else {
 223         size = g_delegate->sizeHint(&option, tip);
 224     }
 225     const QRect desktop = QApplication::desktop()->screenGeometry(m_itemRect.bottomRight());
 226
 227     // m_itemRect defines the area of the item, where the tooltip should be
 228     // shown. Per default the tooltip is shown in the bottom right corner.
 229     // If the tooltip content exceeds the desktop borders, it must be assured that:
 230     // - the content is fully visible
 231     // - the content is not drawn inside m_itemRect
 232     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= desktop.left());
 233     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= desktop.right());
 234     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= desktop.top());
 235     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= desktop.bottom());
 236     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 237         delete tip;
 238         tip = 0;
 239         return;
 240     }
 241
 242     int x = 0;
 243     int y = 0;
 244     if (hasRoomBelow || hasRoomAbove) {
 245         x = QCursor::pos().x() + 16; // TODO: use mouse pointer width instead of the magic value of 16
 246         if (x + size.width() >= desktop.right()) {
 247             x = desktop.right() - size.width();
 248         }
 249         y = hasRoomBelow ? m_itemRect.bottom() : m_itemRect.top() - size.height();
 250     } else {
 251         Q_ASSERT(hasRoomToLeft || hasRoomToRight);
 252         x = hasRoomToRight ? m_itemRect.right() : m_itemRect.left() - size.width();
 253
 254         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 255         // been adjusted, so that no overlapping with m_itemRect occurs.
 256         y = desktop.bottom() - size.height();
 257     }
 258
 259     KToolTip::showTip(QPoint(x, y), tip);
 260 }
 261
 262
 263
 264 void ToolTipManager::startPreviewJob()
 265 {
 266     m_generatingPreview = true;
 267     KIO::PreviewJob* job = KIO::filePreview(KFileItemList() << m_item,
 268                                             PREVIEW_WIDTH,
 269                                             PREVIEW_HEIGHT);
 270     job->setIgnoreMaximumSize(true);
 271
 272     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 273             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 274     connect(job, SIGNAL(failed(const KFileItem&)),
 275             this, SLOT(previewFailed(const KFileItem&)));
 276 }
 277
 278
 279 void ToolTipManager::setPreviewPix(const KFileItem& item,
 280                                    const QPixmap& pixmap)
 281 {
 282     if (m_item.url() != item.url()) {
 283         m_generatingPreview = false;
 284         return;
 285     }
 286
 287     if (m_previewIsLate) {
 288         // always use the maximal width
 289         QPixmap paddedImage(QSize(PREVIEW_WIDTH, pixmap.height()));
 290         paddedImage.fill(Qt::transparent);
 291         QPainter painter(&paddedImage);
 292         painter.drawPixmap((PREVIEW_WIDTH - pixmap.width()) / 2, 0, pixmap);
 293         m_pix = paddedImage;
 294     } else {
 295         m_pix = pixmap;
 296     }
 297     m_preview = true;
 298     m_generatingPreview = false;
 299 }
 300
 301 void ToolTipManager::previewFailed(const KFileItem& item)
 302 {
 303     Q_UNUSED(item);
 304     m_generatingPreview = false;
 305 }
 306
 307 #include "tooltipmanager.moc"