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