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 }
  90
  91 ToolTipManager::~ToolTipManager()
  92 {
  93 }
  94
  95 void ToolTipManager::hideTip()
  96 {
  97     hideToolTip();
  98 }
  99
 100 bool ToolTipManager::eventFilter(QObject* watched, QEvent* event)
 101 {
 102     if ((watched == m_view->viewport()) && (event->type() == QEvent::Leave)) {
 103         hideToolTip();
 104     }
 105
 106     return QObject::eventFilter(watched, event);
 107 }
 108
 109 void ToolTipManager::requestToolTip(const QModelIndex& index)
 110 {
 111     // only request a tooltip for the name column and when no selection or
 112     // drag & drop operation is done (indicated by the left mouse button)
 113     if ((index.column() == DolphinModel::Name) && !(QApplication::mouseButtons() & Qt::LeftButton)) {
 114         m_waitOnPreviewTimer->stop();
 115         KToolTip::hideTip();
 116
 117         m_itemRect = m_view->visualRect(index);
 118         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 119         m_itemRect.moveTo(pos);
 120
 121         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 122         m_item = m_dolphinModel->itemForIndex(dirIndex);
 123
 124         // only start the previewJob when the mouse has been over this item for 200 milliseconds,
 125         // this prevents a lot of useless preview jobs when passing rapidly over a lot of items
 126         m_previewTimer->start(200);
 127         m_previewPixmap = QPixmap();
 128         m_hasDefaultIcon = false;
 129
 130         m_timer->start(500);
 131     } else {
 132         hideToolTip();
 133     }
 134 }
 135
 136 void ToolTipManager::hideToolTip()
 137 {
 138     m_timer->stop();
 139     m_previewTimer->stop();
 140     m_waitOnPreviewTimer->stop();
 141     KToolTip::hideTip();
 142 }
 143
 144 void ToolTipManager::prepareToolTip()
 145 {
 146     if (m_generatingPreview) {
 147         m_waitOnPreviewTimer->start(250);
 148     }
 149
 150     const QString text = m_item.getToolTipText();
 151     if (!m_previewPixmap.isNull()) {
 152         showToolTip(KIcon(m_previewPixmap), text);
 153     } else if (!m_hasDefaultIcon) {
 154         const QPixmap image(KIcon(m_item.iconName()).pixmap(ICON_WIDTH, ICON_HEIGHT));
 155         showToolTip(image, text);
 156         m_hasDefaultIcon = true;
 157     }
 158 }
 159
 160 void ToolTipManager::showToolTip(const QIcon& icon, const QString& text)
 161 {
 162     if (QApplication::mouseButtons() & Qt::LeftButton) {
 163         return;
 164     }
 165
 166     KToolTipItem* tip = new KToolTipItem(icon, text);
 167
 168     KStyleOptionToolTip option;
 169     // TODO: get option content from KToolTip or add KToolTip::sizeHint() method
 170     option.direction      = QApplication::layoutDirection();
 171     option.fontMetrics    = QFontMetrics(QToolTip::font());
 172     option.activeCorner   = KStyleOptionToolTip::TopLeftCorner;
 173     option.palette        = QToolTip::palette();
 174     option.font           = QToolTip::font();
 175     option.rect           = QRect();
 176     option.state          = QStyle::State_None;
 177     option.decorationSize = QSize(32, 32);
 178
 179     const QSize size = g_delegate->sizeHint(option, *tip);
 180     const QRect desktop = QApplication::desktop()->screenGeometry(m_itemRect.bottomRight());
 181
 182     // m_itemRect defines the area of the item, where the tooltip should be
 183     // shown. Per default the tooltip is shown in the bottom right corner.
 184     // If the tooltip content exceeds the desktop borders, it must be assured that:
 185     // - the content is fully visible
 186     // - the content is not drawn inside m_itemRect
 187     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= desktop.left());
 188     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= desktop.right());
 189     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= desktop.top());
 190     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= desktop.bottom());
 191     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 192         delete tip;
 193         tip = 0;
 194         return;
 195     }
 196
 197     int x = 0;
 198     int y = 0;
 199     if (hasRoomBelow || hasRoomAbove) {
 200         x = QCursor::pos().x() + 16; // TODO: use mouse pointer width instead of the magic value of 16
 201         if (x + size.width() >= desktop.right()) {
 202             x = desktop.right() - size.width();
 203         }
 204         y = hasRoomBelow ? m_itemRect.bottom() : m_itemRect.top() - size.height();
 205     } else {
 206         Q_ASSERT(hasRoomToLeft || hasRoomToRight);
 207         x = hasRoomToRight ? m_itemRect.right() : m_itemRect.left() - size.width();
 208
 209         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 210         // been adjusted, so that no overlapping with m_itemRect occurs.
 211         y = desktop.bottom() - size.height();
 212     }
 213
 214     // the ownership of tip is transferred to KToolTip
 215     KToolTip::showTip(QPoint(x, y), tip);
 216 }
 217
 218
 219
 220 void ToolTipManager::startPreviewJob()
 221 {
 222     m_generatingPreview = true;
 223     KIO::PreviewJob* job = KIO::filePreview(KFileItemList() << m_item,
 224                                             PREVIEW_WIDTH,
 225                                             PREVIEW_HEIGHT);
 226
 227     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 228             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 229     connect(job, SIGNAL(failed(const KFileItem&)),
 230             this, SLOT(previewFailed()));
 231 }
 232
 233
 234 void ToolTipManager::setPreviewPix(const KFileItem& item,
 235                                    const QPixmap& pixmap)
 236 {
 237     if ((m_item.url() != item.url()) || pixmap.isNull()) {
 238         // an old preview or an invalid preview has been received
 239         previewFailed();
 240     } else {
 241         m_previewPixmap = pixmap;
 242         m_generatingPreview = false;
 243     }
 244 }
 245
 246 void ToolTipManager::previewFailed()
 247 {
 248     m_generatingPreview = false;
 249 }
 250
 251 #include "tooltipmanager.moc"