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