src/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 <ktooltip.h>
  28 #include <kio/previewjob.h>
  29
  30 #include <QApplication>
  31 #include <QDesktopWidget>
  32 #include <QTimer>
  33 #include <QToolTip>
  34
  35 const int PREVIEW_WIDTH = 256;
  36 const int PREVIEW_HEIGHT = 256;
  37 const int ICON_WIDTH = 128;
  38 const int ICON_HEIGHT = 128;
  39 const int PREVIEW_DELAY = 250;
  40
  41 K_GLOBAL_STATIC(DolphinBalloonTooltipDelegate, g_delegate)
  42
  43 ToolTipManager::ToolTipManager(QAbstractItemView* parent,
  44                                DolphinSortFilterProxyModel* model) :
  45     QObject(parent),
  46     m_view(parent),
  47     m_dolphinModel(0),
  48     m_proxyModel(model),
  49     m_timer(0),
  50     m_previewTimer(0),
  51     m_waitOnPreviewTimer(0),
  52     m_item(),
  53     m_itemRect(),
  54     m_preview(),
  55     m_generatingPreview(),
  56     m_previewIsLate(),
  57     m_previewPass(),
  58     m_emptyRenderedKToolTipItem(),
  59     m_pix()
  60 {
  61     KToolTip::setToolTipDelegate(g_delegate);
  62
  63     m_dolphinModel = static_cast<DolphinModel*>(m_proxyModel->sourceModel());
  64     connect(parent, SIGNAL(entered(const QModelIndex&)),
  65             this, SLOT(requestToolTip(const QModelIndex&)));
  66     connect(parent, SIGNAL(viewportEntered()),
  67             this, SLOT(hideToolTip()));
  68
  69     m_timer = new QTimer(this);
  70     m_timer->setSingleShot(true);
  71     connect(m_timer, SIGNAL(timeout()),
  72             this, SLOT(prepareToolTip()));
  73
  74     m_previewTimer = new QTimer(this);
  75     m_previewTimer->setSingleShot(true);
  76     connect(m_previewTimer, SIGNAL(timeout()),
  77             this, SLOT(startPreviewJob()));
  78
  79     m_waitOnPreviewTimer = new QTimer(this);
  80     m_waitOnPreviewTimer->setSingleShot(true);
  81     connect(m_waitOnPreviewTimer, SIGNAL(timeout()),
  82             this, SLOT(prepareToolTip()));
  83
  84     m_view->viewport()->installEventFilter(this);
  85
  86     m_preview = false;
  87     m_generatingPreview = false;
  88     m_previewIsLate = false;
  89     m_previewPass = 0;
  90     m_pix = QPixmap();
  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     if (index.column() == DolphinModel::Name) {
 114         KToolTip::hideTip();
 115
 116         m_itemRect = m_view->visualRect(index);
 117         const QPoint pos = m_view->viewport()->mapToGlobal(m_itemRect.topLeft());
 118         m_itemRect.moveTo(pos);
 119
 120         const QModelIndex dirIndex = m_proxyModel->mapToSource(index);
 121         m_item = m_dolphinModel->itemForIndex(dirIndex);
 122
 123         // Only start the previewJob when the mouse has been over this item for 200msec,
 124         // this prevents a lot of useless previewJobs (when passing rapidly over a lot of items).
 125         m_previewTimer->start(200);
 126         // reset these variables
 127         m_preview = false;
 128         m_previewIsLate = 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     KToolTip::hideTip();
 142 }
 143
 144 void ToolTipManager::prepareToolTip()
 145 {
 146     if (m_generatingPreview) {
 147         if (m_previewPass == 1) {
 148             // We waited 250msec and the preview is still not finished,
 149             // so show the toolTip with a transparent image of maximal width.
 150             // When the preview finishes, m_previewIsLate will cause
 151             // a direct update of the tooltip, via m_emptyRenderedKToolTipItem.
 152             QPixmap paddedImage(QSize(PREVIEW_WIDTH, 32));
 153             m_previewIsLate = true;
 154             paddedImage.fill(Qt::transparent);
 155             KToolTipItem* toolTip = new KToolTipItem(paddedImage, m_item.getToolTipText());
 156             m_emptyRenderedKToolTipItem = toolTip; // make toolTip accessible everywhere
 157             showToolTip(toolTip);
 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             m_emptyRenderedKToolTipItem->setData(Qt::DecorationRole, KIcon(m_pix));
 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         KToolTipItem* toolTip = new KToolTipItem(icon, m_item.getToolTipText());
 182         showToolTip(toolTip);
 183     }
 184 }
 185
 186 void ToolTipManager::showToolTip(KToolTipItem* tip)
 187 {
 188     KStyleOptionToolTip option;
 189     // TODO: get option content from KToolTip or add KToolTip::sizeHint() method
 190     option.direction      = QApplication::layoutDirection();
 191     option.fontMetrics    = QFontMetrics(QToolTip::font());
 192     option.activeCorner   = KStyleOptionToolTip::TopLeftCorner;
 193     option.palette        = QToolTip::palette();
 194     option.font           = QToolTip::font();
 195     option.rect           = QRect();
 196     option.state          = QStyle::State_None;
 197     option.decorationSize = QSize(32, 32);
 198
 199     QSize size;
 200     if (m_previewIsLate) {
 201         QPixmap paddedImage(QSize(PREVIEW_WIDTH, PREVIEW_HEIGHT));
 202         KToolTipItem* maxiTip = new KToolTipItem(paddedImage, m_item.getToolTipText());
 203         size = g_delegate->sizeHint(&option, maxiTip);
 204         delete maxiTip;
 205         maxiTip = 0;
 206     }
 207     else {
 208         size = g_delegate->sizeHint(&option, tip);
 209     }
 210     const QRect desktop = QApplication::desktop()->screenGeometry(m_itemRect.bottomRight());
 211
 212     // m_itemRect defines the area of the item, where the tooltip should be
 213     // shown. Per default the tooltip is shown in the bottom right corner.
 214     // If the tooltip content exceeds the desktop borders, it must be assured that:
 215     // - the content is fully visible
 216     // - the content is not drawn inside m_itemRect
 217     const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  >= desktop.left());
 218     const bool hasRoomToRight = (m_itemRect.right()  + size.width()  <= desktop.right());
 219     const bool hasRoomAbove   = (m_itemRect.top()    - size.height() >= desktop.top());
 220     const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() <= desktop.bottom());
 221     if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
 222         delete tip;
 223         tip = 0;
 224         return;
 225     }
 226
 227     int x = 0;
 228     if (hasRoomToLeft || hasRoomToRight) {
 229         x = hasRoomToRight ? m_itemRect.right() : m_itemRect.left() - size.width();
 230     } else {
 231         // Put the tooltip at the far right of the screen. The item will be overlapped
 232         // horizontally, but the y-coordinate will be adjusted afterwards so that no overlapping
 233         // occurs vertically.
 234         x = desktop.right() - size.width();
 235     }
 236
 237     int y = 0;
 238     if (hasRoomBelow || hasRoomAbove) {
 239         y = hasRoomBelow ? m_itemRect.bottom() : m_itemRect.top() - size.height();
 240     } else {
 241         // Put the tooltip at the bottom of the screen. The x-coordinate has already
 242         // been adjusted, so that no overlapping with m_itemRect occurs.
 243         y = desktop.bottom() - size.height();
 244     }
 245
 246     KToolTip::showTip(QPoint(x, y), tip);
 247 }
 248
 249
 250
 251 void ToolTipManager::startPreviewJob()
 252 {
 253     m_generatingPreview = true;
 254     KIO::PreviewJob* job = KIO::filePreview(KUrl::List() << m_item.url(),
 255                                             PREVIEW_WIDTH,
 256                                             PREVIEW_HEIGHT);
 257     job->setIgnoreMaximumSize(true);
 258
 259     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
 260             this, SLOT(setPreviewPix(const KFileItem&, const QPixmap&)));
 261     connect(job, SIGNAL(failed(const KFileItem&)),
 262             this, SLOT(previewFailed(const KFileItem&)));
 263 }
 264
 265
 266 void ToolTipManager::setPreviewPix(const KFileItem& item,
 267                                    const QPixmap& pixmap)
 268 {
 269     if (m_item.url() != item.url()) {
 270         return;
 271     }
 272
 273     QPixmap icon = pixmap;
 274     // only paint borders if the pixmap is opaque
 275     if (!icon.hasAlphaChannel()) {
 276         // TODO: Make code from IconManager for drawing a border accessible for
 277         // other classes (the following code has been adapted from IconManager).
 278         // The frame is painted on top of the pixmap, this is needed to keep
 279         // the text preview visually nice (the previewer adds ugly borders).
 280         QPainter painter;
 281         // make a buffer pixmap, tends to crash when 'icon' is directly painted ...
 282         QPixmap framedIcon(icon.size().width(), pixmap.size().height());
 283         framedIcon.fill();
 284         const int width = framedIcon.width() - 1;
 285         const int height = framedIcon.height() - 1;
 286
 287         // draw the pixmap
 288         painter.begin(&framedIcon);
 289         painter.drawPixmap(0,0, icon);
 290
 291         // draw the frame
 292         painter.setRenderHint(QPainter::Antialiasing, false);
 293         painter.setPen(QColor(0, 0, 0));
 294         painter.drawRect(0, 0, width - 0, height - 1);
 295         painter.drawRect(1, 1, width - 2, height - 2);
 296         painter.setPen(QColor(255, 255, 255));
 297         painter.drawRect(2, 2, width - 4, height - 4);
 298
 299         painter.end();
 300         icon = framedIcon;
 301
 302         // provide an alpha channel for the frame
 303         QPixmap alphaChannel(icon.size());
 304         alphaChannel.fill();
 305
 306         QPainter alphaPainter(&alphaChannel);
 307         alphaPainter.setBrush(Qt::NoBrush);
 308         alphaPainter.setRenderHint(QPainter::Antialiasing, false);
 309         alphaPainter.setPen(QColor(32, 32, 32));
 310         alphaPainter.drawRect(0, 0, width, height);
 311         alphaPainter.setPen(QColor(64, 64, 64));
 312         alphaPainter.drawRect(1, 1, width - 2, height - 2);
 313
 314         icon.setAlphaChannel(alphaChannel);
 315     }
 316
 317     if (m_previewIsLate) {
 318         // always use the maximal width
 319         QPixmap paddedImage(QSize(PREVIEW_WIDTH, icon.height()));
 320         paddedImage.fill(Qt::transparent);
 321         QPainter painter(&paddedImage);
 322         painter.drawPixmap((PREVIEW_WIDTH - icon.width()) / 2, 0, icon);
 323         m_pix = paddedImage;
 324     } else {
 325         m_pix = icon;
 326     }
 327     m_preview = true;
 328     m_generatingPreview = false;
 329 }
 330
 331 void ToolTipManager::previewFailed(const KFileItem& item)
 332 {
 333     Q_UNUSED(item);
 334     m_generatingPreview = false;
 335 }
 336
 337 #include "tooltipmanager.moc"