workspace/plasma/applets/kickoff/ui/tabbar.cpp

   1 /*
   2     Copyright 2007 Robert Knight <robertknight@gmail.com>
   3
   4     This library is free software; you can redistribute it and/or
   5     modify it under the terms of the GNU Library General Public
   6     License as published by the Free Software Foundation; either
   7     version 2 of the License, or (at your option) any later version.
   8
   9     This library 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 GNU
  12     Library General Public License for more details.
  13
  14     You should have received a copy of the GNU Library General Public License
  15     along with this library; see the file COPYING.LIB.  If not, write to
  16     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17     Boston, MA 02110-1301, USA.
  18 */
  19
  20 // Own
  21 #include "ui/tabbar.h"
  22
  23 // KDE
  24 #include <KGlobalSettings>
  25 #include <KColorScheme>
  26
  27 // Qt
  28 #include <QIcon>
  29 #include <QMouseEvent>
  30 #include <QPainter>
  31
  32 #include <QGradient>
  33 #include <QLinearGradient>
  34
  35 #include <Plasma/Plasma>
  36 #include <Plasma/Animator>
  37 #include <Plasma/Theme>
  38 #include <Plasma/FrameSvg>
  39
  40 using namespace Kickoff;
  41
  42 TabBar::TabBar(QWidget *parent)
  43         : QTabBar(parent),
  44         m_hoveredTabIndex(-1),
  45         m_switchOnHover(true),
  46         m_animateSwitch(true),
  47         m_animProgress(1.0)
  48 {
  49     m_lastIndex[0] = -1;
  50     connect(this, SIGNAL(currentChanged(int)), this, SLOT(startAnimation()));
  51
  52     m_tabSwitchTimer.setSingleShot(true);
  53     connect(&m_tabSwitchTimer, SIGNAL(timeout()), this, SLOT(switchToHoveredTab()));
  54     setMouseTracking(true);
  55     setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
  56     setUsesScrollButtons(false);
  57
  58     background = new Plasma::FrameSvg(this);
  59     background->setImagePath("dialogs/kickoff");
  60     background->setEnabledBorders(
  61         Plasma::FrameSvg::BottomBorder |
  62         Plasma::FrameSvg::LeftBorder |
  63         Plasma::FrameSvg::RightBorder
  64     );
  65     background->resizeFrame(size());
  66     background->setElementPrefix("plain");
  67
  68     connect(background, SIGNAL(repaintNeeded()), this, SLOT(update()));
  69 }
  70
  71 void TabBar::setShape(Shape shape)
  72 {
  73     resize(0, 0);    // This is required, so that the custom implementation of tabSizeHint,
  74     // which expands the tabs to the full width of the widget does not pick up
  75     // the previous width, e.g. if the panel is moved from the bottom to the left
  76     QTabBar::setShape(shape);
  77     resize(sizeHint());
  78 }
  79
  80 void TabBar::setCurrentIndexWithoutAnimation(int index)
  81 {
  82     disconnect(this, SIGNAL(currentChanged(int)), this, SLOT(startAnimation()));
  83     setCurrentIndex(index);
  84     storeLastIndex();
  85     connect(this, SIGNAL(currentChanged(int)), this, SLOT(startAnimation()));
  86     animationFinished();
  87 }
  88
  89 void TabBar::setSwitchTabsOnHover(bool switchOnHover)
  90 {
  91     m_switchOnHover = switchOnHover;
  92 }
  93
  94 bool TabBar::switchTabsOnHover() const
  95 {
  96     return m_switchOnHover;
  97 }
  98
  99 void TabBar::setAnimateSwitch(bool animateSwitch)
 100 {
 101     m_animateSwitch = animateSwitch;
 102 }
 103
 104 bool TabBar::animateSwitch()
 105 {
 106     return m_animateSwitch;
 107 }
 108
 109 QSize TabBar::tabSize(int index) const
 110 {
 111     QSize hint;
 112     const QFontMetrics metrics(KGlobalSettings::smallestReadableFont());
 113     const QSize textSize = metrics.size(Qt::TextHideMnemonic, tabText(index));
 114     hint.rwidth() = qMax(iconSize().width(), textSize.width());
 115     hint.rheight() = iconSize().height() + textSize.height();
 116     hint.rwidth() += 4 * TAB_CONTENTS_MARGIN;
 117     hint.rheight() += 2 * TAB_CONTENTS_MARGIN;
 118     return hint;
 119 }
 120
 121 void TabBar::storeLastIndex()
 122 {
 123     // if first run
 124     if (m_lastIndex[0] == -1) {
 125         m_lastIndex[1] = currentIndex();
 126     }
 127     m_lastIndex[0] = m_lastIndex[1];
 128     m_lastIndex[1] = currentIndex();
 129 }
 130
 131 int TabBar::lastIndex() const
 132 {
 133     return m_lastIndex[0];
 134 }
 135
 136 QSize TabBar::tabSizeHint(int index) const
 137 {
 138     QSize hint = tabSize(index);
 139     int minwidth = 0;
 140     int minheight = 0;
 141
 142     Shape s = shape();
 143     switch (s) {
 144     case RoundedSouth:
 145     case TriangularSouth:
 146     case RoundedNorth:
 147     case TriangularNorth:
 148         if (count() > 0) {
 149             for (int i = count() - 1; i >= 0; i--) {
 150                 minwidth += tabSize(i).width();
 151             }
 152             if (minwidth < width()) {
 153                 hint.rwidth() += (width() - minwidth) / count();
 154             }
 155         }
 156         break;
 157     case RoundedWest:
 158     case TriangularWest:
 159     case RoundedEast:
 160     case TriangularEast:
 161         if (count() > 0) {
 162             for (int i = count() - 1; i >= 0; i--) {
 163                 minheight += tabSize(i).height();
 164             }
 165             if (minheight < height()) {
 166                 hint.rheight() += (height() - minheight) / count();
 167             }
 168         }
 169         hint.rwidth() = qMax(hint.width(), width());
 170         break;
 171     }
 172     return hint;
 173 }
 174
 175 QSize TabBar::sizeHint() const
 176 {
 177     int width = 0;
 178     int height = 0;
 179
 180     if (isVertical()) {
 181         for (int i = count() - 1; i >= 0; i--) {
 182             height += tabSize(i).height();
 183         }
 184
 185         width = tabSize(0).width();
 186     } else {
 187         for (int i = count() - 1; i >= 0; i--) {
 188             width += tabSize(i).width();
 189         }
 190
 191         height = tabSize(0).height();
 192     }
 193     return QSize(width, height);
 194 }
 195
 196 QPainterPath TabBar::tabPath(const QRect &_r)
 197 {
 198     const int radius = 6;
 199     Shape s = shape();
 200     QPainterPath path;
 201     QRect r = _r;
 202
 203     switch (s) {
 204     case RoundedSouth:
 205     case TriangularSouth:
 206         r.adjust(0, 0, 0, -3);
 207         path.moveTo(r.topLeft());
 208         // Top left corner
 209         path.quadTo(r.topLeft() + QPoint(radius, 0), r.topLeft() + QPoint(radius, radius));
 210         path.lineTo(r.bottomLeft() + QPoint(radius, -radius));
 211         // Bottom left corner
 212         path.quadTo(r.bottomLeft() + QPoint(radius, 0), r.bottomLeft() + QPoint(radius * 2, 0));
 213         path.lineTo(r.bottomRight() + QPoint(-radius * 2, 0));
 214         // Bottom right corner
 215         path.quadTo(r.bottomRight() + QPoint(-radius, 0), r.bottomRight() + QPoint(-radius, -radius));
 216         path.lineTo(r.topRight() + QPoint(-radius, radius));
 217         // Top right corner
 218         path.quadTo(r.topRight() + QPoint(-radius, 0), r.topRight());
 219         break;
 220     case RoundedNorth:
 221     case TriangularNorth:
 222         r.adjust(0, 3, 0, 1);
 223         path.moveTo(r.bottomLeft());
 224         // Bottom left corner
 225         path.quadTo(r.bottomLeft() + QPoint(radius, 0), r.bottomLeft() + QPoint(radius, -radius));
 226         // Top left corner
 227         path.lineTo(r.topLeft() + QPoint(radius, radius));
 228         path.quadTo(r.topLeft() + QPoint(radius, 0), r.topLeft() + QPoint(radius * 2, 0));
 229         // Top right corner
 230         path.lineTo(r.topRight() + QPoint(-radius * 2, 0));
 231         path.quadTo(r.topRight() + QPoint(-radius, 0), r.topRight() + QPoint(-radius, radius));
 232         // Bottom right corner
 233         path.lineTo(r.bottomRight() + QPoint(-radius, -radius));
 234         path.quadTo(r.bottomRight() + QPoint(-radius, 0), r.bottomRight());
 235         break;
 236     case RoundedWest:
 237     case TriangularWest:
 238         r.adjust(3, 0, 1, 0);
 239         path.moveTo(r.topRight());
 240         // Top right corner
 241         path.lineTo(r.topRight());
 242         path.quadTo(r.topRight() + QPoint(0, radius), r.topRight() + QPoint(-radius, radius));
 243         // Top left corner
 244         path.lineTo(r.topLeft() + QPoint(radius, radius));
 245         path.quadTo(r.topLeft() + QPoint(0, radius), r.topLeft() + QPoint(0, radius * 2));
 246         // Bottom left corner
 247         path.lineTo(r.bottomLeft() + QPoint(0, -radius * 2));
 248         path.quadTo(r.bottomLeft() + QPoint(0, -radius), r.bottomLeft() + QPoint(radius, -radius));
 249         // Bottom right corner
 250         path.lineTo(r.bottomRight() + QPoint(-radius, -radius));
 251         path.quadTo(r.bottomRight() + QPoint(0, -radius), r.bottomRight());
 252         break;
 253     case RoundedEast:
 254     case TriangularEast:
 255         r.adjust(0, 0, -3, 0);
 256         path.moveTo(r.topLeft());
 257         // Top left corner
 258         path.quadTo(r.topLeft() + QPoint(0, radius), r.topLeft() + QPoint(radius, radius));
 259         // Top right corner
 260         path.lineTo(r.topRight() + QPoint(-radius, radius));
 261         path.quadTo(r.topRight() + QPoint(0, radius), r.topRight() + QPoint(0, radius * 2));
 262         // Bottom right corner
 263         path.lineTo(r.bottomRight() + QPoint(0, -radius * 2));
 264         path.quadTo(r.bottomRight() + QPoint(0, -radius), r.bottomRight() + QPoint(-radius, -radius));
 265         // Bottom left corner
 266         path.lineTo(r.bottomLeft() + QPoint(radius, -radius));
 267         path.quadTo(r.bottomLeft() + QPoint(0, -radius), r.bottomLeft());
 268         break;
 269     }
 270
 271     return path;
 272 }
 273
 274 void TabBar::paintEvent(QPaintEvent *event)
 275 {
 276     Q_UNUSED(event)
 277     QPainter painter(this);
 278     //int numTabs = count();
 279     int currentTab = currentIndex();
 280
 281     background->paintFrame(&painter);
 282
 283     //bool ltr = painter.layoutDirection() == Qt::LeftToRight; // Not yet used
 284     painter.setFont(KGlobalSettings::smallestReadableFont());
 285
 286     // Drawing Tabborders
 287     QRect movingRect;
 288
 289     if (m_currentAnimRect.isNull()) {
 290         movingRect = tabRect(currentIndex());
 291     } else {
 292         movingRect = m_currentAnimRect;
 293     }
 294     QPainterPath path = tabPath(movingRect);
 295
 296     painter.save();
 297     painter.setPen(QPen(palette().base(), 1));
 298
 299     painter.setRenderHint(QPainter::Antialiasing);
 300     painter.fillPath(path, palette().base());
 301
 302     painter.restore();
 303
 304     QFontMetrics metrics(painter.font());
 305     int textHeight = metrics.height();
 306
 307     for (int i = 0; i < count(); i++) {
 308         QRect rect = tabRect(i).adjusted(TAB_CONTENTS_MARGIN, TAB_CONTENTS_MARGIN,
 309                                          -TAB_CONTENTS_MARGIN, -TAB_CONTENTS_MARGIN);
 310         // draw tab icon
 311         QRect iconRect = rect;
 312         iconRect.setBottom(iconRect.bottom() - textHeight);
 313         iconRect.adjust(0, (isVertical() ? 1 : 0) * TAB_CONTENTS_MARGIN + 3, 0, 0);
 314         tabIcon(i).paint(&painter, iconRect);
 315
 316         // draw tab text
 317         if (i != currentTab || m_animProgress < 0.9) {
 318             //painter.setPen(QPen(KColorScheme(QPalette::Active).foreground(KColorScheme::InactiveText), 0));
 319             painter.setPen(Plasma::Theme::defaultTheme()->color(Plasma::Theme::TextColor));
 320         } else {
 321             painter.setPen(QPen(KColorScheme(QPalette::Active).foreground(KColorScheme::NormalText), 0));
 322         }
 323         QRect textRect = rect;
 324         textRect.setTop(textRect.bottom() - textHeight);
 325         painter.drawText(textRect, Qt::AlignCenter | Qt::TextHideMnemonic, tabText(i));
 326     }
 327 }
 328
 329 void TabBar::leaveEvent(QEvent *event)
 330 {
 331     Q_UNUSED(event)
 332     m_hoveredTabIndex = -1;
 333 }
 334
 335 void TabBar::mouseMoveEvent(QMouseEvent *event)
 336 {
 337     m_hoveredTabIndex = tabAt(event->pos());
 338     if (m_switchOnHover && m_hoveredTabIndex > -1 && m_hoveredTabIndex != currentIndex()) {
 339         m_tabSwitchTimer.stop();
 340         m_tabSwitchTimer.start(50);
 341     }
 342 }
 343
 344 void TabBar::resizeEvent(QResizeEvent* event)
 345 {
 346     QTabBar::resizeEvent(event);
 347     m_currentAnimRect = tabRect(currentIndex());
 348
 349     background->resizeFrame(event->size());
 350
 351     update();
 352 }
 353
 354 void TabBar::switchToHoveredTab()
 355 {
 356     if (m_hoveredTabIndex < 0 || m_hoveredTabIndex == currentIndex()) {
 357         return;
 358     }
 359
 360     if (m_animateSwitch) {
 361         setCurrentIndex(m_hoveredTabIndex);
 362     } else {
 363         setCurrentIndexWithoutAnimation(m_hoveredTabIndex);
 364     }
 365 }
 366
 367 void TabBar::startAnimation()
 368 {
 369     storeLastIndex();
 370     Plasma::Animator::self()->customAnimation(10, 150, Plasma::Animator::EaseInOutCurve, this, "onValueChanged");
 371
 372 }
 373
 374 void TabBar::onValueChanged(qreal value)
 375 {
 376     if ((m_animProgress = value) == 1.0) {
 377         animationFinished();
 378         return;
 379     }
 380
 381     // animation rect
 382     QRect rect = tabRect(currentIndex());
 383     QRect lastRect = tabRect(lastIndex());
 384     int x = isHorizontal() ? (int)(lastRect.x() - value * (lastRect.x() - rect.x())) : rect.x();
 385     int y = isHorizontal() ? rect.y() : (int)(lastRect.y() - value * (lastRect.y() - rect.y()));
 386     QSizeF sz = lastRect.size() - value * (lastRect.size() - rect.size());
 387     m_currentAnimRect = QRect(x, y, (int)(sz.width()), (int)(sz.height()));
 388     update();
 389 }
 390
 391 void TabBar::animationFinished()
 392 {
 393     m_currentAnimRect = QRect();
 394     update();
 395 }
 396
 397 bool TabBar::isVertical() const
 398 {
 399     Shape s = shape();
 400     if (s == RoundedWest ||
 401             s == RoundedEast ||
 402             s == TriangularWest ||
 403             s == TriangularEast) {
 404         return true;
 405     }
 406     return false;
 407 }
 408
 409 bool TabBar::isHorizontal() const
 410 {
 411     return !isVertical();
 412 }
 413
 414 #include "tabbar.moc"