workspace/ksysguard/gui/SensorDisplayLib/BarGraph.cc

   1 /*
   2     KSysGuard, the KDE System Guard
   3
   4     Copyright (c) 1999, 2000 Chris Schlaeger <cs@kde.org>
   5
   6     This program is free software; you can redistribute it and/or
   7     modify it under the terms of the GNU General Public
   8     License version 2 or at your option version 3 as published by
   9     the Free Software Foundation.
  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 Free Software
  18     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19
  20 */
  21
  22 #include <assert.h>
  23 #include <string.h>
  24
  25 #include <QPainter>
  26
  27 #include <kdebug.h>
  28 #include <kiconloader.h>
  29
  30 #include "StyleEngine.h"
  31
  32 #include "BarGraph.h"
  33
  34 BarGraph::BarGraph( QWidget *parent )
  35   : QWidget( parent )
  36 {
  37   bars = 0;
  38   minValue = 0.0;
  39   maxValue = 100.0;
  40   lowerLimit = upperLimit = 0.0;
  41   lowerLimitActive = upperLimitActive = false;
  42
  43   normalColor = KSGRD::Style->firstForegroundColor();
  44   alarmColor = KSGRD::Style->alarmColor();
  45   mBackgroundColor = KSGRD::Style->backgroundColor();
  46   fontSize = KSGRD::Style->fontSize();
  47
  48   // Anything smaller than this does not make sense.
  49   setMinimumSize( 16, 16 );
  50   setSizePolicy( QSizePolicy( QSizePolicy::Expanding,
  51                  QSizePolicy::Expanding ) );
  52 }
  53
  54 BarGraph::~BarGraph()
  55 {
  56 }
  57
  58 bool BarGraph::addBar( const QString &footer )
  59 {
  60   samples.resize( bars + 1 );
  61   samples[ bars++ ] = 0.0;
  62   footers.append( footer );
  63
  64   return true;
  65 }
  66
  67 bool BarGraph::removeBar( uint idx )
  68 {
  69   if ( idx >= bars ) {
  70     kDebug(1215) << "BarGraph::removeBar: idx " << idx << " out of range "
  71                   << bars << endl;
  72     return false;
  73   }
  74
  75   samples.resize( --bars );
  76   footers.removeAll( footers.at( idx ) );
  77   update();
  78
  79   return true;
  80 }
  81
  82 void BarGraph::updateSamples( const QVector<double> &newSamples )
  83 {
  84   samples = newSamples;
  85   update();
  86 }
  87
  88 void BarGraph::changeRange( double min, double max )
  89 {
  90   minValue = min;
  91   maxValue = max;
  92 }
  93
  94 void BarGraph::paintEvent( QPaintEvent* )
  95 {
  96   int w = width();
  97   int h = height();
  98
  99   QPainter p( this );
 100
 101   p.fillRect(0,0,w, h, mBackgroundColor);
 102
 103   p.setBrush( palette().color( QPalette::Light) );
 104   p.setFont( QFont( p.font().family(), fontSize ) );
 105   QFontMetrics fm( p.font() );
 106
 107   /* Draw white line along the bottom and the right side of the
 108    * widget to create a 3D like look. */
 109   p.drawLine( 0, h - 1, w - 1, h - 1 );
 110   p.drawLine( w - 1, 0, w - 1, h - 1 );
 111
 112   p.setClipRect( 1, 1, w - 2, h - 2 );
 113
 114   if ( bars > 0 ) {
 115     int barWidth = ( w - 2 ) / bars;
 116     uint b;
 117     /* Labels are only printed underneath the bars if the labels
 118      * for all bars are smaller than the bar width. If a single
 119      * label does not fit no label is shown. */
 120     bool showLabels = true;
 121     for ( b = 0; b < bars; b++ )
 122       if ( fm.width( footers[ b ] ) > barWidth )
 123         showLabels = false;
 124
 125     int barHeight;
 126     if ( showLabels )
 127       barHeight = h - 2 - ( 2 * fm.lineSpacing() ) - 2;
 128     else
 129       barHeight = h - 2;
 130
 131     for ( uint b = 0; b < bars; b++ ) {
 132       int topVal = (int) ( (float)barHeight / maxValue *
 133                            ( samples[ b ] - minValue ) );
 134       /* TODO: This widget does not handle negative values properly. */
 135       if ( topVal < 0 )
 136         topVal = 0;
 137
 138       for ( int i = 0; i < barHeight && i < topVal; i += 2 ) {
 139         if ( ( upperLimitActive && samples[ b ] > upperLimit ) ||
 140              ( lowerLimitActive && samples[ b ] < lowerLimit ) )
 141           p.setPen( alarmColor.light( static_cast<int>( 30 + ( 70.0 /
 142                                       ( barHeight + 1 ) * i ) ) ) );
 143         else
 144           p.setPen( normalColor.light( static_cast<int>( 30 + ( 70.0 /
 145                                       ( barHeight + 1 ) * i ) ) ) );
 146         p.drawLine( b * barWidth + 3, barHeight - i, ( b + 1 ) * barWidth - 3,
 147                     barHeight - i );
 148       }
 149
 150       if ( ( upperLimitActive && samples[ b ] > upperLimit ) ||
 151            ( lowerLimitActive && samples[ b ] < lowerLimit ) )
 152         p.setPen( alarmColor );
 153       else
 154         p.setPen( normalColor );
 155
 156       if ( showLabels ) {
 157         p.drawText( b * barWidth + 3, h - ( 2 * fm.lineSpacing() ) - 2,
 158                     barWidth - 2 * 3, fm.lineSpacing(), Qt::AlignCenter,
 159                     footers[ b ] );
 160         p.drawText( b * barWidth + 3, h - fm.lineSpacing() - 2,
 161                     barWidth - 2 * 3, fm.lineSpacing(), Qt::AlignCenter,
 162                     QString( "%1" ).arg( samples[ b ] ) );
 163       }
 164     }
 165   }
 166
 167   p.end();
 168 }
 169
 170 #include "BarGraph.moc"