init();connect(ui->treeWidget,SIGNAL(itemChanged(QTreeWidgetItem*, int)),this,SLOT(treeItemChanged(QTreeWidgetItem*,int)));

void Widget::init()
{ui->treeWidget->setHeaderLabels(QStringList()<<"123"<<"234");//设置列名ui->treeWidget->clear();QTreeWidgetItem* group1=new QTreeWidgetItem(ui->treeWidget);group1->setText(0,"group1");group1->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);group1->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem11=new QTreeWidgetItem(group1);subItem11->setText(0,"subItem11");subItem11->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem11->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem12=new QTreeWidgetItem(group1);subItem12->setText(0,"subItem12");subItem12->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem12->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem13=new QTreeWidgetItem(group1);subItem13->setText(0,"subItem13");subItem13->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem13->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem14=new QTreeWidgetItem(group1);subItem14->setText(0,"subItem14");subItem14->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem14->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* group2=new QTreeWidgetItem(ui->treeWidget);group2->setText(0,"group2");group2->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);group2->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem21=new QTreeWidgetItem(group2);subItem21->setText(0,"subItem21");subItem21->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem21->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem22=new QTreeWidgetItem(group2);subItem22->setText(0,"subItem22");subItem22->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem22->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem23=new QTreeWidgetItem(group2);subItem23->setText(0,"subItem23");subItem23->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem23->setCheckState(0,Qt::Unchecked);QTreeWidgetItem* subItem24=new QTreeWidgetItem(group2);subItem24->setText(0,"subItem24");subItem24->setFlags(Qt::ItemIsUserCheckable|Qt::ItemIsEnabled|Qt::ItemIsSelectable);subItem24->setCheckState(0,Qt::Unchecked);}void Widget::updateParentItem(QTreeWidgetItem *item)
{QTreeWidgetItem* parent=item->parent();if(parent==NULL){return;}int selectedCount=0;int childCount=parent->childCount();for(int i=0;i<childCount;i++){QTreeWidgetItem* childItem=parent->child(i);if(childItem->checkState(0)==Qt::Checked){selectedCount++;}}if(selectedCount<=0){parent->setCheckState(0,Qt::Unchecked);}else if(selectedCount>0&&selectedCount<childCount){parent->setCheckState(0,Qt::PartiallyChecked);}else if(selectedCount==childCount){parent->setCheckState(0,Qt::Checked);}
}void Widget::treeItemChanged(QTreeWidgetItem *item, int column)
{//QString itemText=item->text(0);if(Qt::Checked==item->checkState(0)){//QTreeWidgetItem* parent=item->parent();int count=item->childCount();if(count>0){for(int i=0;i<count;i++){item->child(i)->setCheckState(0,Qt::Checked);}}else{updateParentItem(item);}}else if(Qt::Unchecked==item->checkState(0)){int count=item->childCount();if(count>0){for(int i=0;i<count;i++){item->child(i)->setCheckState(0,Qt::Unchecked);}}else{updateParentItem(item);}}
}