Qt实现多行表头

• 设计思路
  利用两个表格，一个表格作为表头，一个作为表格内容，表头表格高度设置为对应行数高度之和，两表采用竖向布局，竖向滚动条放置于两表右侧

• 滚动条
  内容表格横向滚动条保持不变，竖向滚动条禁用，自定义滚动条并绑定内容表格，滚动条的显示与隐藏通过其范围变化动态设置

  connect(table_content->horizontalScrollBar(), &QScrollBar::valueChanged, table_header->horizontalScrollBar(), &QScrollBar::setSliderPosition);
  connect(table_header->horizontalScrollBar(), &QScrollBar::valueChanged, table_content->horizontalScrollBar(), &QScrollBar::setSliderPosition);
  connect(verticalScrollBar, &QScrollBar::rangeChanged, this, &Widget::verticalScrollBarHideOrShow);
  

• 滚动条设置代码

  void Widget::verticalScrollBarHideOrShow(int min, int max)
  {
      if(min == max)
      {
          verticalScrollBar->setHidden(true);
      }
      else
      {
          verticalScrollBar->setHidden(false);
      }
  }
  

• 完整代码

  table_header = new QTableWidget(this);
  table_content = new QTableWidget(this);
  table_header->setObjectName("table_header");
  table_content->setObjectName("table_content");
  
  table_header->horizontalHeader()->setVisible(false);
  table_header->verticalHeader()->setVisible(false);
  table_header->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
  table_header->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
  table_header->setFrameShape(QFrame::NoFrame);
  table_header->setFocusPolicy(Qt::NoFocus);
  table_header->setEditTriggers(QAbstractItemView::NoEditTriggers);
  table_header->setSelectionMode(QAbstractItemView::NoSelection);
  
  table_header->setRowCount(2);
  table_header->setColumnCount(5);
  table_header->setFixedHeight(table_header->rowHeight(0) + table_header->rowHeight(1));
  
  table_header->setSpan(0, 0, 2, 1);
  table_header->setItem(0, 0, new QTableWidgetItem("header1"));
  table_header->item(0, 0)->setTextAlignment(Qt::AlignCenter);
  
  table_header->setSpan(0, 1, 1, 2);
  table_header->setItem(0, 1, new QTableWidgetItem("header2"));
  table_header->item(0, 1)->setTextAlignment(Qt::AlignCenter);
  table_header->setItem(1, 1, new QTableWidgetItem("header21"));
  table_header->item(1, 1)->setTextAlignment(Qt::AlignCenter);
  table_header->setItem(1, 2, new QTableWidgetItem("header22"));
  table_header->item(1, 2)->setTextAlignment(Qt::AlignCenter);
  
  table_header->setSpan(0, 3, 1, 2);
  table_header->setItem(0, 3, new QTableWidgetItem("header3"));
  table_header->item(0, 3)->setTextAlignment(Qt::AlignCenter);
  table_header->setItem(1, 3, new QTableWidgetItem("header31"));
  table_header->item(1, 3)->setTextAlignment(Qt::AlignCenter);
  table_header->setItem(1, 4, new QTableWidgetItem("header32"));
  table_header->item(1, 4)->setTextAlignment(Qt::AlignCenter);
  
  table_content->horizontalHeader()->setVisible(false);
  table_content->verticalHeader()->setVisible(false);
  table_content->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
  table_content->setFrameShape(QFrame::NoFrame);
  table_content->setFocusPolicy(Qt::NoFocus);
  table_content->setSelectionBehavior(QAbstractItemView::SelectRows);
  table_content->setSelectionMode(QAbstractItemView::SingleSelection);
  table_content->setAlternatingRowColors(true);
  table_content->setEditTriggers(QAbstractItemView::NoEditTriggers);
  
  table_content->setColumnCount(5);
  table_content->setRowCount(10);
  for(int i=0; i<15; i++)
  {
      table_content->setItem(i/5, i%5, new QTableWidgetItem("item"+QString::number(i/5)+QString::number(i%5)));
  }
  
  verticalScrollBar = new QScrollBar(Qt::Vertical, this);
  table_content->setVerticalScrollBar(verticalScrollBar);
  
  connect(table_content->horizontalScrollBar(), &QScrollBar::valueChanged, table_header->horizontalScrollBar(), &QScrollBar::setSliderPosition);
  connect(table_header->horizontalScrollBar(), &QScrollBar::valueChanged, table_content->horizontalScrollBar(), &QScrollBar::setSliderPosition);
  connect(verticalScrollBar, &QScrollBar::rangeChanged, this, &Widget::verticalScrollBarHideOrShow);
  
  QVBoxLayout *vb_no_vertical_scrollbar = new QVBoxLayout();
  vb_no_vertical_scrollbar->addWidget(table_header);
  vb_no_vertical_scrollbar->addWidget(table_content);
  vb_no_vertical_scrollbar->setSpacing(0);
  
  QHBoxLayout *hb_tables = new QHBoxLayout(this);
  hb_tables->addLayout(vb_no_vertical_scrollbar);
  hb_tables->addWidget(verticalScrollBar);
  
  this->setStyleSheet("QTableWidget#table_header::item{background-color:lightgray;} QTableWidget#table_header{gridline-color:gray;} QTableWidget#table_content::item::selected{background-color:lightgreen;color:white;}");
  

• 运行结果