kget/plasma/applet/piechartwidget.cpp

   1 /***************************************************************************
   2  *                                                                         *
   3  *   This program is free software; you can redistribute it and/or modify  *
   4  *   it under the terms of the GNU General Public License as published by  *
   5  *   the Free Software Foundation; either version 2 of the License, or     *
   6  *   (at your option) any later version.                                   *
   7  *
   8  *   Copyright (C) 2007 by Javier Goday <jgoday@gmail.com>
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA .        *
  19  ***************************************************************************/
  20
  21 #include "piechartwidget.h"
  22
  23 #include <math.h>
  24
  25 #include <QPainter>
  26 #include <QFontMetrics>
  27 #include <QStyleOptionGraphicsItem>
  28
  29 #include <KDebug>
  30 #include <KLocale>
  31 #include <KGlobal>
  32 #include <KColorCollection>
  33
  34 #define TOP_MARGIN 10
  35 #define LEFT_MARGIN 15
  36 #define PIE_SIZE 140
  37
  38 class PieChartWidget::PrivateData
  39 {
  40 public:
  41     PrivateData()
  42     {}
  43
  44     QString name;
  45     bool isActive;
  46     int length;
  47     int activeLength;
  48 };
  49
  50 class PieChartWidget::Private : public Plasma::Widget
  51 {
  52 public:
  53     Private(Plasma::Widget *parent) : Plasma::Widget(parent),
  54                 m_colors("Oxygen.colors"),
  55                 size(QSize(300, 200)),
  56                 bottomMargin(10),
  57                 totalSize(0),
  58                 emitUpdateGeometrySignal(false)
  59     {
  60         setGeometry(QRect((size.width()/2 - PIE_SIZE/2), TOP_MARGIN, PIE_SIZE + 2, PIE_SIZE + 2));
  61     }
  62
  63     // returns the size of the private inner widget
  64     QSizeF sizeHint() const
  65     {
  66         return QSizeF(PIE_SIZE + 2, PIE_SIZE + 2);
  67     }
  68
  69     // Paint the private widget, who cares to draw only the line items representing the data
  70     void paintWidget(QPainter *p, const QStyleOptionGraphicsItem *option,
  71                         QWidget *widget)
  72     {
  73         Q_UNUSED(option)
  74         Q_UNUSED(widget)
  75
  76         if(totalSize > 0) {
  77             kDebug() << "About to repaint the inner widget" << endl;
  78
  79             p->save();
  80             p->setRenderHint(QPainter::Antialiasing);
  81
  82             QRect rect(2, 2, PIE_SIZE -2, PIE_SIZE - 2);
  83             int angle = 90 * 16; // 0
  84
  85             QPen totalPen;
  86             QPen activePen;
  87
  88             // total pen
  89             totalPen.setWidth(2);
  90             totalPen.setColor(Qt::darkGray);
  91             totalPen.setStyle(Qt::SolidLine);
  92
  93             activePen.setWidth(2);
  94             activePen.setColor(Qt::white);
  95             activePen.setStyle(Qt::SolidLine);
  96
  97             for(int i = 0; i < data.size(); i++) {
  98                 QBrush brush(m_colors.color(i*6 + 4));
  99
 100                 PrivateData portion = data [data.keys().at(i)];
 101
 102                 float pieOpacity = 0.67;
 103                 float activePieOpacity = 0.84;
 104                 int current_angle = angle;
 105
 106                 p->save();
 107
 108                 if (portion.isActive) {
 109                     p->setPen(activePen);
 110                 }
 111                 else {
 112                     p->setPen(totalPen);
 113                 }
 114
 115                 p->setOpacity(pieOpacity);
 116
 117                 int totalPercent = (int) portion.length * 100/ totalSize;
 118                 angle = drawPie(p, rect, angle, totalPercent, brush);
 119                 p->restore();
 120
 121                 p->save();
 122                 // draw the active length
 123                 p->setOpacity(activePieOpacity);
 124                 p->setPen(Qt::NoPen);
 125                 int activePercent = (int) portion.activeLength * 100/ totalSize;
 126                 drawPie(p, QRect(rect.x() + 15, rect.y() + 15, rect.width() - 30, rect.height() - 30),
 127                                 current_angle, activePercent, brush);
 128
 129                 p->restore();
 130             }
 131
 132             p->restore();
 133         }
 134         else {
 135             p->setPen(Qt::white);
 136             p->drawText(QRect(2, 2, PIE_SIZE -2, PIE_SIZE - 2), Qt::AlignCenter, i18n("n/a"));
 137         }
 138     }
 139
 140     int drawPie(QPainter *p, const QRect &rect, int angle, int percent, const QBrush &brush)
 141     {
 142         int end_angle = -1 * percent * 36/10 * 16;
 143
 144         p->setBrush(brush);
 145         p->drawPie(rect, angle, end_angle);
 146
 147         return end_angle + angle;
 148     }
 149
 150     // Draw the graph legend with the names of the data
 151     void drawLegend(const QString &name, QPainter *p, const QColor &color, int count)
 152     {
 153         p->save();
 154         p->setPen(Qt::NoPen);
 155         p->setBrush(QBrush(color));
 156         p->drawRoundRect(QRect(LEFT_MARGIN, count * 20 + size.height() - bottomMargin + TOP_MARGIN, 10, 10));
 157         p->setPen(Qt::SolidLine);
 158         p->setPen(Qt::white);
 159
 160         // the data name
 161         p->drawText(QRect(LEFT_MARGIN + 14, count * 20 + size.height () - bottomMargin + TOP_MARGIN - 5, 200, 20), Qt::AlignLeft, p->fontMetrics().elidedText(name, Qt::ElideLeft, 200));
 162         // the data percent
 163         p->drawText(QRect(LEFT_MARGIN + 236, count * 20 + size.height () - bottomMargin + TOP_MARGIN - 5, 70, 20), Qt::AlignLeft,
 164         KGlobal::locale()->formatByteSize(data [name].length));
 165
 166         p->restore();
 167     }
 168
 169     KColorCollection m_colors;
 170     QSize size;
 171     QMap <QString, PrivateData> data;
 172     int bottomMargin;
 173     int totalSize;
 174     bool emitUpdateGeometrySignal;
 175 };
 176
 177 PieChartWidget::PieChartWidget(Widget *parent)
 178     : Plasma::Widget(parent),
 179     d(new Private(this))
 180 {
 181 }
 182
 183 PieChartWidget::~PieChartWidget()
 184 {
 185     delete d;
 186 }
 187
 188 void PieChartWidget::addData(QString name, int length)
 189 {
 190     addData(name, length, 0, false);
 191 }
 192
 193 void PieChartWidget::addData(QString name, int length, int activeLength)
 194 {
 195     addData(name, length, activeLength, false);
 196 }
 197
 198 void PieChartWidget::addData(QString name, int length, int activeLength, bool active)
 199 {
 200     if (!d->data.contains(name)) {
 201         d->data [name] = PrivateData ();
 202
 203         // update the widget size
 204         d->bottomMargin += 20;
 205         d->size.setHeight (d->size.height() + 20);
 206
 207         d->emitUpdateGeometrySignal = true;
 208     }
 209
 210     d->data [name].name = name;
 211     d->data [name].length = length;
 212     d->data [name].activeLength = activeLength;
 213     d->data [name].isActive = active;
 214
 215     d->totalSize += length;
 216 }
 217
 218 void PieChartWidget::removeData(const QString &key)
 219 {
 220     d->data.remove(key);
 221     emit geometryChanged();
 222 }
 223
 224 void PieChartWidget::clear()
 225 {
 226     d->totalSize = 0;
 227     d->emitUpdateGeometrySignal = false;
 228 }
 229
 230 void PieChartWidget::updateView()
 231 {
 232     // ensure that only the data points are repainted, called after the setData methods
 233     if (d->emitUpdateGeometrySignal) {
 234        d->emitUpdateGeometrySignal = false;
 235        emit geometryChanged();
 236     }
 237     d->updateGeometry();
 238 }
 239
 240 QSizeF PieChartWidget::sizeHint() const
 241 {
 242     return d->size;
 243 }
 244
 245 void PieChartWidget::paintWidget(QPainter *p, const QStyleOptionGraphicsItem *option, QWidget *widget)
 246 {
 247     Q_UNUSED(option)
 248     Q_UNUSED(widget)
 249
 250     kDebug() << "About to draw the parent widget" ;
 251
 252     for(int i = 0; i < d->data.size(); i++) {
 253         d->drawLegend(d->data.keys().at(i), p, d->m_colors.color(i*6 + 4), i);
 254     }
 255 }