src/tooltips/ktooltipwindow.cpp

   1 /*******************************************************************************
   2  *   Copyright (C) 2008 by Fredrik Höglund <fredrik@kde.org>                   *
   3  *   Copyright (C) 2008 by Konstantin Heil <konst.heil@stud.uni-heidelberg.de> *
   4  *   Copyright (C) 2009 by Peter Penz <peter.penz@gmx.at>                      *
   5  *                                                                             *
   6  *   This program is free software; you can redistribute it and/or modify      *
   7  *   it under the terms of the GNU General Public License as published by      *
   8  *   the Free Software Foundation; either version 2 of the License, or         *
   9  *   (at your option) any later version.                                       *
  10  *                                                                             *
  11  *   This program is distributed in the hope that it will be useful,           *
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             *
  14  *   GNU General Public License for more details.                              *
  15  *                                                                             *
  16  *   You should have received a copy of the GNU General Public License         *
  17  *   along with this program; if not, write to the                             *
  18  *   Free Software Foundation, Inc.,                                           *
  19  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA                *
  20  *******************************************************************************/
  21
  22 #include "ktooltipwindow_p.h"
  23
  24 #include <kcolorscheme.h>
  25
  26 #include <QPainter>
  27 #include <QVBoxLayout>
  28
  29 #ifdef Q_WS_X11
  30     #include <QX11Info>
  31 #endif
  32
  33 KToolTipWindow::KToolTipWindow(QWidget* content) :
  34     QWidget(0)
  35 {
  36     setAttribute(Qt::WA_TranslucentBackground);
  37     setWindowFlags(Qt::ToolTip | Qt::FramelessWindowHint);
  38
  39     QVBoxLayout* layout = new QVBoxLayout(this);
  40     layout->addWidget(content);
  41 }
  42
  43 KToolTipWindow::~KToolTipWindow()
  44 {
  45 }
  46
  47 void KToolTipWindow::paintEvent(QPaintEvent* event)
  48 {
  49     Q_UNUSED(event);
  50
  51     QPainter painter(this);
  52
  53     QColor toColor = palette().brush(QPalette::ToolTipBase).color();
  54     QColor fromColor = KColorScheme::shade(toColor, KColorScheme::LightShade, 0.2);
  55
  56 #ifdef Q_WS_X11
  57     const bool haveAlphaChannel = QX11Info::isCompositingManagerRunning();
  58 #else
  59     const bool haveAlphaChannel = false;
  60 #endif
  61     if (haveAlphaChannel) {
  62         painter.setRenderHint(QPainter::Antialiasing);
  63         painter.translate(0.5, 0.5);
  64         toColor.setAlpha(220);
  65         fromColor.setAlpha(220);
  66     }
  67
  68     QLinearGradient gradient(QPointF(0.0, 0.0), QPointF(0.0, height()));
  69     gradient.setColorAt(0.0, fromColor);
  70     gradient.setColorAt(1.0, toColor);
  71     painter.setPen(Qt::NoPen);
  72     painter.setBrush(gradient);
  73
  74     const QRect rect(0, 0, width(), height());
  75     if (haveAlphaChannel) {
  76         const qreal radius = 5.0;
  77
  78         QPainterPath path;
  79         path.moveTo(rect.left(), rect.top() + radius);
  80         arc(path, rect.left()  + radius, rect.top()    + radius, radius, 180, -90);
  81         arc(path, rect.right() - radius, rect.top()    + radius, radius,  90, -90);
  82         arc(path, rect.right() - radius, rect.bottom() - radius, radius,   0, -90);
  83         arc(path, rect.left()  + radius, rect.bottom() - radius, radius, 270, -90);
  84         path.closeSubpath();
  85
  86         painter.drawPath(path);
  87     } else {
  88         painter.drawRect(rect);
  89     }
  90 }
  91
  92 void KToolTipWindow::arc(QPainterPath& path, qreal cx, qreal cy, qreal radius, qreal angle, qreal sweeplength)
  93 {
  94     path.arcTo(cx-radius, cy-radius, radius * 2, radius * 2, angle, sweeplength);
  95 }
  96
  97 #include "ktooltipwindow_p.moc"