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_previewPass(0),
  56     m_pix()
  57 {
  58     KToolTip::setToolTipDelegate(g_delegate);
  59
  60     m_dolphinModel = static_cast<DolphinModel*>(m_proxyModel->sourceModel());
  61     connect(parent, SIGNAL(entered(const QModelIndex&)),
  62             this, SLOT(requestToolTip(const QModelIndex&)));
  63     connect(parent, SIGNAL(viewportEntered()),
  64             this, SLOT(hideToolTip()));
  65
  66     m_timer = new QTimer(this);
  67     m_timer->setSingleShot(true);
  68     connect(m_timer, SIGNAL(timeout()),
  69             this, SLOT(prepareToolTip()));
  70
  71     m_previewTimer = new QTimer(this);
  72     m_previewTimer->setSingleShot(true);
  73     connect(m_previewTimer, SIGNAL(timeout()),
  74             this, SLOT(startPreviewJob()));
  75
  76     m_waitOnPreviewTimer = new QTimer(this);
  77     m_waitOnPreviewTimer->setSingleShot(true);
  78     connect(m_waitOnPreviewTimer, SIGNAL(timeout()),
  79             this, SLOT(prepareToolTip()));
  80
  81     // When the mousewheel is used, the items don't get a hovered indication
  82     // (Qt-issue #200665). To assure that the tooltip still gets hidden,
  83     // the scrollbars are observed.
  84     connect(parent->horizontalScrollBar(), SIGNAL(valueChanged(int)),
  85             this, SLOT(hideTip()));
  86     connect(parent->verticalScrollBar(), SIGNAL(valueChanged(int)),
  87             this, SLOT(hideTip()));
  88
  89     m_view->viewport()->installEventFilter(this);
  90 }
  91
  92 ToolTipManager::~ToolTipManager()
  93 {
  94 }
  95
  96 void ToolTipManager::hideTip()
  97 {
  98     hideToolTip();
  99 }
 100
 101 bool ToolTipManager::eventFilter(QObject* watched, QEvent* event)
 102 {
 103     if ((watched == m_view->viewport()) && (event->type() == QEvent::Leave)) {
 104         hideToolTip();
 105     }
 106
 107     return QObject::eventFilter(watched, event);
 108 }
 109
 110 void ToolTipManager::requestToolTip(const QModelIndex& index)
 111 {
 112     // only request a tooltip for the name column and when no selection or
 113     // drag & drop operation is done (indicated by the left mouse button)
 114     if ((index.column() == DolphinModel::Name) && !(QApplication::mouseButtons() & Qt::LeftButton)) {
 115         m_waitOnPreviewTimer->stop();
 116         KToolTip::hideTip();
 117
 118         m_itemRect = m_view->visualRect(index);
 119         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 120         m_itemRect.moveTo(pos);
 121
 122         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 123         m_item = m_dolphinModel->itemForIndex(dirIndex);
 124
 125         // only start the previewJob when the mouse has been over this item for 200 milliseconds,
 126         // this prevents a lot of useless preview jobs when passing rapidly over a lot of items
 127         m_previewTimer->start(200);
 128         m_preview = false;
 129         m_previewPass = 0;
 130
 131         m_timer->start(500);
 132     } else {
 133         hideToolTip();
 134     }
 135 }
 136
 137 void ToolTipManager::hideToolTip()
 138 {
 139     m_timer->stop();
 140     m_previewTimer->stop();
 141     m_waitOnPreviewTimer->stop();
 142     KToolTip::hideTip();
 143 }
 144
 145 void ToolTipManager::prepareToolTip()
 146 {
 147     if (m_generatingPreview) {
 148         if (m_previewPass == 1) {
 149             // We waited 250msec and the preview is still not finished,
 150             // so show default icon as fallback.
 151             QPixmap image(KIcon(m_item.iconName()).pixmap(ICON_WIDTH, ICON_HEIGHT));
 152             showToolTip(image, m_item.getToolTipText());
 153         }
 154
 155         ++m_previewPass;
 156         m_waitOnPreviewTimer->start(250);
 157     } else {
 158         KIcon icon;
 159         if (m_preview) {
 160             // We got a preview.
 161             icon = KIcon(m_pix);
 162         } else {
 163             // No preview, so use an icon.
 164             // Force a 128x128 icon, a 256x256 one is far too big.
 165             const QPixmap pixmap = KIcon(m_item.iconName()).pixmap(ICON_WIDTH, ICON_HEIGHT);
 166             icon = KIcon(pixmap);
 167         }
 168
 169         showToolTip(icon, m_item.getToolTipText());
 170     }
 171 }
 172
 173 void ToolTipManager::showToolTip(const QIcon& icon, const QString& text)
 174 {
 175     if (QApplication::mouseButtons() & Qt::LeftButton) {
 176         return;
 177     }
 178
 179     KToolTipItem* tip = new KToolTipItem(icon, text);
 180
 181     KStyleOptionToolTip option;
 182     // TODO: get option content from KToolTip or add KToolTip::sizeHint() method
 183     option.direction      = QApplication::layoutDirection();
 184     option.fontMetrics    = QFontMetrics(QToolTip::font());
 185     option.activeCorner   = KStyleOptionToolTip::TopLeftCorner;
 186     option.palette        = QToolTip::palette();
 187     option.font           = QToolTip::font();
 188     option.rect           = QRect();
 189     option.state          = QStyle::State_None;
 190     option.decorationSize = QSize(32, 32);
 191
 192     const QSize size = g_delegate->sizeHint(option, *tip);
 193     const QRect desktop = QApplication::desktop()->screenGeometry(m_itemRect.bottomRight());
 194
 195     // m_itemRect defines the area of the item, where the tooltip should be
 196     // shown. Per default the tooltip is shown in the bottom right corner.
 197     // If the tooltip content exceeds the desktop borders, it must be assured that:
 198     // - the content is fully visible
 199     // - the content is not drawn inside m_itemRect
 200     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= desktop.left());
 201     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= desktop.right());
 202     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= desktop.top());
 203     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= desktop.bottom());
 204     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 205         delete tip;
 206         tip = 0;
 207         return;
 208     }
 209
 210     int x = 0;
 211     int y = 0;
 212     if (hasRoomBelow || hasRoomAbove) {
 213         x = QCursor::pos().x() + 16; // TODO: use mouse pointer width instead of the magic value of 16
 214         if (x + size.width() >= desktop.right()) {
 215             x = desktop.right() - size.width();
 216         }
 217         y = hasRoomBelow ? m_itemRect.bottom() : m_itemRect.top() - size.height();
 218     } else {
 219         Q_ASSERT(hasRoomToLeft || hasRoomToRight);
 220         x = hasRoomToRight ? m_itemRect.right() : m_itemRect.left() - size.width();
 221
 222         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 223         // been adjusted, so that no overlapping with m_itemRect occurs.
 224         y = desktop.bottom() - size.height();
 225     }
 226
 227     // the ownership of tip is transferred to KToolTip
 228     KToolTip::showTip(QPoint(x, y), tip);
 229 }
 230
 231
 232
 233 void ToolTipManager::startPreviewJob()
 234 {
 235     m_generatingPreview = true;
 236     KIO::PreviewJob* job = KIO::filePreview(KFileItemList() << m_item,
 237                                             PREVIEW_WIDTH,
 238                                             PREVIEW_HEIGHT);
 239
 240     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 241             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 242     connect(job, SIGNAL(failed(const KFileItem&)),
 243             this, SLOT(previewFailed(const KFileItem&)));
 244 }
 245
 246
 247 void ToolTipManager::setPreviewPix(const KFileItem& item,
 248                                    const QPixmap& pixmap)
 249 {
 250     if ((m_item.url() != item.url()) || pixmap.isNull()) {
 251         // an old preview or an invalid preview has been received
 252         m_generatingPreview = false;
 253         return;
 254     }
 255
 256     m_pix = pixmap;
 257     m_preview = true;
 258     m_generatingPreview = false;
 259 }
 260
 261 void ToolTipManager::previewFailed(const KFileItem& item)
 262 {
 263     Q_UNUSED(item);
 264     m_generatingPreview = false;
 265 }
 266
 267 #include "tooltipmanager.moc"