src/kitemviews/kitemlistgroupheader.cpp

   1 /*
   2  * SPDX-FileCopyrightText: 2011 Peter Penz <peter.penz19@gmail.com>
   3  *
   4  * Based on the Itemviews NG project from Trolltech Labs
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8
   9 #include "kstandarditemlistgroupheader.h"
  10
  11 #include "kitemlistview.h"
  12
  13 #include <QGraphicsSceneResizeEvent>
  14 #include <QPainter>
  15 #include <QStyleOptionGraphicsItem>
  16
  17 KItemListGroupHeader::KItemListGroupHeader(QGraphicsWidget* parent) :
  18     QGraphicsWidget(parent),
  19     m_dirtyCache(true),
  20     m_role(),
  21     m_data(),
  22     m_styleOption(),
  23     m_scrollOrientation(Qt::Vertical),
  24     m_itemIndex(-1),
  25     m_separatorColor(),
  26     m_roleColor(),
  27     m_roleBounds()
  28 {
  29 }
  30
  31 KItemListGroupHeader::~KItemListGroupHeader()
  32 {
  33 }
  34
  35 void KItemListGroupHeader::setRole(const QByteArray& role)
  36 {
  37     if (m_role != role) {
  38         const QByteArray previous = m_role;
  39         m_role = role;
  40         update();
  41         roleChanged(role, previous);
  42     }
  43 }
  44
  45 QByteArray KItemListGroupHeader::role() const
  46 {
  47     return m_role;
  48 }
  49
  50 void KItemListGroupHeader::setData(const QVariant& data)
  51 {
  52     if (m_data != data) {
  53         const QVariant previous = m_data;
  54         m_data = data;
  55         update();
  56         dataChanged(data, previous);
  57     }
  58 }
  59
  60 QVariant KItemListGroupHeader::data() const
  61 {
  62     return m_data;
  63 }
  64
  65 void KItemListGroupHeader::setStyleOption(const KItemListStyleOption& option)
  66 {
  67     if (m_styleOption == option) {
  68         return;
  69     }
  70
  71     const KItemListStyleOption previous = m_styleOption;
  72     m_styleOption = option;
  73     m_dirtyCache = true;
  74     styleOptionChanged(option, previous);
  75 }
  76
  77 const KItemListStyleOption& KItemListGroupHeader::styleOption() const
  78 {
  79     return m_styleOption;
  80 }
  81
  82 void KItemListGroupHeader::setScrollOrientation(Qt::Orientation orientation)
  83 {
  84     if (m_scrollOrientation != orientation) {
  85         const Qt::Orientation previous = m_scrollOrientation;
  86         m_scrollOrientation = orientation;
  87         if (orientation == Qt::Vertical) {
  88             m_dirtyCache = true;
  89         }
  90         scrollOrientationChanged(orientation, previous);
  91     }
  92 }
  93
  94 void KItemListGroupHeader::setItemIndex(int index)
  95 {
  96     if (m_itemIndex != index) {
  97         const int previous = m_itemIndex;
  98         m_itemIndex = index;
  99         m_dirtyCache = true;
 100         itemIndexChanged(m_itemIndex, previous);
 101     }
 102 }
 103
 104 int KItemListGroupHeader::itemIndex() const
 105 {
 106     return m_itemIndex;
 107 }
 108
 109 Qt::Orientation KItemListGroupHeader::scrollOrientation() const
 110 {
 111     return m_scrollOrientation;
 112 }
 113
 114 void KItemListGroupHeader::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
 115 {
 116     Q_UNUSED(painter)
 117     Q_UNUSED(option)
 118     Q_UNUSED(widget)
 119
 120     if (m_dirtyCache) {
 121         updateCache();
 122     }
 123
 124     paintSeparator(painter, m_separatorColor);
 125     paintRole(painter, m_roleBounds, m_roleColor);
 126 }
 127
 128 void KItemListGroupHeader::roleChanged(const QByteArray& current, const QByteArray& previous)
 129 {
 130     Q_UNUSED(current)
 131     Q_UNUSED(previous)
 132 }
 133
 134 void KItemListGroupHeader::dataChanged(const QVariant& current, const QVariant& previous)
 135 {
 136     Q_UNUSED(current)
 137     Q_UNUSED(previous)
 138 }
 139
 140 void KItemListGroupHeader::styleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 141 {
 142     Q_UNUSED(current)
 143     Q_UNUSED(previous)
 144 }
 145
 146 void KItemListGroupHeader::scrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 147 {
 148     Q_UNUSED(current)
 149     Q_UNUSED(previous)
 150 }
 151
 152 void KItemListGroupHeader::itemIndexChanged(int current, int previous)
 153 {
 154     Q_UNUSED(current)
 155     Q_UNUSED(previous)
 156 }
 157
 158 void KItemListGroupHeader::resizeEvent(QGraphicsSceneResizeEvent* event)
 159 {
 160     QGraphicsWidget::resizeEvent(event);
 161     if (event->oldSize().height() != event->newSize().height()) {
 162         m_dirtyCache = true;
 163     }
 164 }
 165
 166 void KItemListGroupHeader::updateCache()
 167 {
 168     Q_ASSERT(m_dirtyCache);
 169
 170     // Calculate the role- and line-color. No alphablending is used for
 171     // performance reasons.
 172     const QColor c1 = textColor();
 173     const QColor c2 = baseColor();
 174     m_separatorColor = mixedColor(c1, c2, 10);
 175     m_roleColor = mixedColor(c1, c2, 60);
 176
 177     const int padding = qMax(1, m_styleOption.padding);
 178     const int horizontalMargin = qMax(2, m_styleOption.horizontalMargin);
 179
 180     const QFontMetrics fontMetrics(m_styleOption.font);
 181     const qreal roleHeight = fontMetrics.height();
 182
 183     const int y = (m_scrollOrientation == Qt::Vertical) ? padding : horizontalMargin;
 184
 185     m_roleBounds = QRectF(horizontalMargin + padding,
 186                           y,
 187                           size().width() - 2 * padding - horizontalMargin,
 188                           roleHeight);
 189
 190     m_dirtyCache = false;
 191 }
 192
 193 QColor KItemListGroupHeader::mixedColor(const QColor& c1, const QColor& c2, int c1Percent)
 194 {
 195     Q_ASSERT(c1Percent >= 0 && c1Percent <= 100);
 196
 197     const int c2Percent = 100 - c1Percent;
 198     return QColor((c1.red()   * c1Percent + c2.red()   * c2Percent) / 100,
 199                   (c1.green() * c1Percent + c2.green() * c2Percent) / 100,
 200                   (c1.blue()  * c1Percent + c2.blue()  * c2Percent) / 100);
 201 }
 202
 203 QPalette::ColorRole KItemListGroupHeader::normalTextColorRole() const
 204 {
 205     return QPalette::Text;
 206 }
 207
 208 QPalette::ColorRole KItemListGroupHeader::normalBaseColorRole() const
 209 {
 210     return QPalette::Window;
 211 }
 212
 213 QColor KItemListGroupHeader::textColor() const
 214 {
 215     const QPalette::ColorGroup group = isActiveWindow() ? QPalette::Active : QPalette::Inactive;
 216     return styleOption().palette.color(group, normalTextColorRole());
 217 }
 218
 219 QColor KItemListGroupHeader::baseColor() const
 220 {
 221     const QPalette::ColorGroup group = isActiveWindow() ? QPalette::Active : QPalette::Inactive;
 222     return styleOption().palette.color(group, normalBaseColorRole());
 223 }
 224