用自定义的QSortFilterProxyModel实现条件过滤，使qtableview中只显示满足条件的行信息

条件过滤，使qtableview中只显示满足条件的行信息"/>

用自定义的QSortFilterProxyModel实现条件过滤，使qtableview中只显示满足条件的行信息

在实际开发中，qtableview是qt客户端页面中最常用的控件之一。运用qtableview的同时，也会存在着先对初始数据进行过滤，然后在qtableview上展示的只有满足条件的那些信息。或者在不同的条件下要展示出不同的满足条件的行信息。

第一种方法，就是我们在将数据设置在qtableview的model之前，将满足条件的信息筛选出来，然后直接填入model.

第二种方法，就是先不对数据进行处理，直接将数据塞入qtableview的model，然后再给qtableview设置一个筛选代理proxymodel(QSortFilterProxyModel)对model中数据进行刷选，然后展示出来的就是能满足条件的model.

1、先看项目目录结构

2、添加数据model文件， studentmodel.h，studentmodel.cpp

studentmodel.h#include <QAbstractItemModel>
class Student
{
public:QString name;  //姓名int age;       //年龄int height;    //身高int weight;    //体重
};
Q_DECLARE_METATYPE(Student);class StudentModel : public QAbstractItemModel
{Q_OBJECT
public:enum {column_name = 0,column_age,column_height,column_weight};explicit StudentModel(QObject *parent = nullptr);void setInfo(QList<Student>& studentList);void clear();QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override;QModelIndex parent(const QModelIndex &index) const override;int rowCount(const QModelIndex &parent = QModelIndex()) const override;int columnCount(const QModelIndex &parent = QModelIndex()) const override;QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;private:QList<Student> m_studentList;};

studentmodel.cpp#include "studentmodel.h"StudentModel::StudentModel(QObject *parent): QAbstractItemModel{parent}
{}void StudentModel::setInfo(QList<Student>& studentList)
{m_studentList = studentList;beginInsertRows(QModelIndex(), 0, m_studentList.size() -1);endInsertRows();
}void StudentModel::clear()
{m_studentList.clear();beginResetModel();endResetModel();
}QModelIndex StudentModel::index(int row, int column, const QModelIndex &parent) const
{return createIndex(row, column, nullptr);
}QModelIndex StudentModel::parent(const QModelIndex &index) const
{return QModelIndex();
}int StudentModel::rowCount(const QModelIndex &parent) const
{return m_studentList.size();
}int StudentModel::columnCount(const QModelIndex &parent) const
{return 4;
}QVariant StudentModel::headerData(int section, Qt::Orientation orientation, int role) const
{if (orientation == Qt::Vertical){return QVariant();}if (role == Qt::DisplayRole){switch (section){case column_name:return tr("name");break;case column_age:return tr("age");break;case column_height:return tr("height");break;case column_weight:return tr("weight");break;}}return QVariant();
}QVariant StudentModel::data(const QModelIndex &index, int role) const
{int row = index.row();int col = index.column();auto info = m_studentList.at(row);if (role == Qt::DisplayRole){switch (col){case column_name:return info.name;break;case column_age:return QString::number(info.age);break;case column_height:return QString::number(info.height);break;case column_weight:return QString::number(info.weight);break;}}else if (role == Qt::UserRole){return QVariant::fromValue<Student>(m_studentList[row]);}return QVariant();
}

3、添加筛选过滤model文件， studentproxymodel.h，studentproxymodel.cpp

studentproxymodel.h#include <QSortFilterProxyModel>
#include "studentmodel.h"class StudentProxyModel : public QSortFilterProxyModel
{Q_OBJECT
public:explicit StudentProxyModel(QObject *parent = nullptr);protected:// 返回true表示source的资源包含在代理model中virtual bool filterAcceptsRow(int source_row, const QModelIndex &source_parent) const;};

#include "studentproxymodel.h"StudentProxyModel::StudentProxyModel(QObject *parent): QSortFilterProxyModel{parent}
{}bool StudentProxyModel::filterAcceptsRow(int source_row, const QModelIndex &source_parent) const
{QModelIndex source = sourceModel()->index(source_row, 0, source_parent);// 资源Enttiy节点进行过滤Student student = source.data(Qt::UserRole).value<Student>();//过滤条件：如果年龄小于20，或身高小于170，或体重小于50，则不显示，返回falseif(student.age < 20){return false;}if(student.height < 170){return false;}if(student.weight < 50){return false;}return true;
}

4、在widget.cpp中添加测试代码

widget.cpp#include "widget.h"
#include "ui_widget.h"
#include <QTableView>
#include <QBoxLayout>
#include "studentmodel.h"
#include "studentproxymodel.h"Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);QHBoxLayout* layout = new QHBoxLayout(this);this->setLayout(layout);QTableView* tableView = new QTableView(this);layout->addWidget(tableView);Student stu1;stu1.age = 18;stu1.name = "sandy";stu1.height = 170;stu1.weight = 50;Student stu2;stu1.age = 23;stu1.name = "alice";stu1.height = 168;stu1.weight = 55;Student stu3;stu1.age = 20;stu1.name = "make";stu1.height = 178;stu1.weight = 60;Student stu4;stu1.age = 22;stu1.name = "jason";stu1.height = 180;stu1.weight = 70;QList<Student> studentList;studentList.clear();studentList.append(stu1);studentList.append(stu2);studentList.append(stu3);studentList.append(stu4);StudentModel* model = new StudentModel(this);StudentProxyModel* proxyModel = new StudentProxyModel(this);proxyModel->setSourceModel(model);tableView->setModel(proxyModel);model->setInfo(studentList);
}Widget::~Widget()
{delete ui;
}

5、结果显示满足过滤条件（只有make和jason满足过滤条件）