qt绘制甘特图

重写paintEvent事件，代码如下

void xx::paintEvent(QPaintEvent *event){
  QPainter painter(this);
  
  //绘制x，y轴，_maxWidth为y轴边距
  painter.drawLine(QPoint(_maxWidth,20),QPoint(width(),20));
  painter.drawLine(QPoint(_maxWidth, 20), QPoint(_maxWidth,height()));
  //绘制刻度，_maxMinutes为x轴最大刻度
  int num = (_maxMinutes - _minMinutes) / 5;
  int interval = (width() - _maxWidth) / num;
  
  for (int index = 0; index != num;++index){
    painter.drawLine(QPoint(_maxWidth + index * interval, 20), QPoint(_maxWidth + index * interval, 15));
    painter.drawText(QPoint(_maxWidth + index * interval, 10), QString::number(_minMinutes + index*5));
  }

  num = _dataMap.size();
  interval = (height() - 20) / (num + 2);
  //绘制数据_dataMap，QString（y轴坐标名称：起始时间-结束时间& 起始时间-结束时间）
  QMap<int, QString>::iterator it = _dataMap.begin();
  int index = 1;
  for (; it != _dataMap.end(); ++it){
    QStringList list = it.value().split(":");
    if (list.size() != 2) continue;
 
    painter.drawText(QPoint(0, 20 + interval * index), list[0]);
    painter.drawLine(QPoint(_maxWidth, 20 + interval * index), QPoint(_maxWidth  + 5, 20 + interval * index));

    for each (QString var in list[1].split("&")){
      if (var.isEmpty()) continue;
      QStringList interalList = var.split("-");
      if (interalList.size() != 2) continue;
      int x = (interalList[0].toDouble() / _maxMinutes) * (width() - _maxWidth);
      int x1 = (interalList[1].toDouble() / _maxMinutes) * (width() - _maxWidth);
      painter.drawLine(QPoint(_maxWidth + x, 20 + interval * index), QPoint(_maxWidth + x1, 20 + interval * index));
    }

    ++index;
  }
}

效果如下

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