src/tooltips/ktooltipdelegate.h

   1 /***************************************************************************
   2  *   Copyright (C) 2008 by Fredrik Höglund <fredrik@kde.org>               *
   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 #ifndef KTOOLTIPDELEGATE_H
  21 #define KTOOLTIPDELEGATE_H
  22
  23 #include <QFontMetrics>
  24 #include <QFont>
  25 #include <QObject>
  26 #include <QPalette>
  27 #include <QRect>
  28 #include <QStyle>
  29 #include <QSize>
  30
  31 class KStyleOptionToolTip;
  32 class KToolTipItem;
  33 class QPainter;
  34 class QRegion;
  35
  36 class KStyleOptionToolTip
  37 {
  38 public:
  39     KStyleOptionToolTip();
  40     enum Corner { TopLeftCorner, TopRightCorner, BottomLeftCorner, BottomRightCorner, NoCorner };
  41
  42     Qt::LayoutDirection direction;
  43     QFontMetrics fontMetrics;
  44     QPalette palette;
  45     QRect rect;
  46     QStyle::State state;
  47     QFont font;
  48     QSize decorationSize;
  49     Corner activeCorner;
  50 };
  51
  52 /**
  53  * KToolTipDelegate is responsible for providing the size hint and
  54  * painting the tooltips.
  55  */
  56 class KToolTipDelegate : public QObject
  57 {
  58     Q_OBJECT
  59 public:
  60      KToolTipDelegate();
  61      virtual ~KToolTipDelegate();
  62
  63      virtual QSize sizeHint(const KStyleOptionToolTip &option, const KToolTipItem &item) const;
  64
  65      /**
  66       * If haveAlphaChannel() returns true, the paint device will be filled with
  67       * Qt::transparent when this function is called, otherwise the content is
  68       * undefined.
  69       */
  70      virtual void paint(QPainter *painter,
  71                         const KStyleOptionToolTip &option,
  72                         const KToolTipItem &item) const;
  73
  74      /**
  75       * Reimplement this function to specify the region of the tooltip
  76       * that accepts input. Any mouse events that occur outside this
  77       * region will be sent to the widget below the tooltip.
  78       *
  79       * The default implementation returns a region containing the
  80       * bounding rect of the tooltip.
  81       *
  82       * This function will only be called if haveAlphaChannel()
  83       * returns true.
  84       */
  85      virtual QRegion inputShape(const KStyleOptionToolTip &option) const;
  86
  87      /**
  88       * Reimplement this function to specify a shape mask for the tooltip.
  89       *
  90       * The default implementation returns a region containing the
  91       * bounding rect of the tooltip.
  92       *
  93       * This function will only be called if haveAlphaChannel()
  94       * returns false.
  95       */
  96      virtual QRegion shapeMask(const KStyleOptionToolTip &option) const;
  97
  98 protected:
  99      /**
 100       * Returns true if the tooltip has an alpha channel, and false
 101       * otherwise.
 102       *
 103       * Implementors should assume that this condition may change at
 104       * any time during the runtime of the application, as compositing
 105       * can be enabled or disabled in the window manager.
 106       */
 107      bool haveAlphaChannel() const;
 108 };
 109
 110 #endif