Qt5入门学习——模型/视图结构

简介: Qt5入门学习——模型/视图结构

文章目录

概述

基本概念

简单文件目录浏览器【简单示例】

模型(Model)

自定义模型【示例】

视图(View)

表格数据显示【示例】

代理(Delegate)

利用Delegate设计表格控件【示例】


Qt的模型/视图结构分为三部分:模型(Model)、视图(View)和代理(Delegate)。其中,模型与数据源通信,并为其他部件提供接口;而视图从模型中获得用来引用数据条目的模型索引(Model Index)。在视图中,代理负责绘制数据条目,当编辑条目时,代理和模型直接进行通信。模型/视图/代理之间通过信号和槽进行通信,

20200319155111579.png

概述

基本概念

  • 模型(model)

InterView框架中的所有模型都基于抽象基类QAbstractItemModel类,此类由QProxyModel、 QAbstractListModel、 QAbstractTableModel、QAbstractProxyModel、 QDirModel、 QFileSystemModel、QHelpContentModel 和 QStandardItemModel类继承。其中, QAbstractListModel

类和QAbstractTableModel类是列表和表格模型的抽象基类,如果需要实现列表或表格模型,则应从这两个类继承。完成QStringList存储的QStringListModel继承自QAbstractListModel类,而与数据库有关的QSqlQueryModel类继承自QAbstractTableModel类; QAbstractProxyModel类是代理模型的抽象类;QDirModel类是文件和目录的存储模型。


  • 视图(view)

InterView框架中的所有视图都基于抽象基类QAbstractItemView类,此类由QColumnView、 QHeaderView、 QListView、 QTableView和QTreeView类继承。其中, QListView类由QUndoView类和QListWidget类继承; QTableView类由QTableWidget类继承; QTreeView类由QTreeWidget类继承。而QListWidget类、QTableWidget类和QTreeWidget类实际上已经包含了数据,是模型/视图集成在一起的类。


  • 代理(delegate)

InterView框架中的所有代理都基于抽象基类QAbstractItemDelegate类,此类由QItemDelegate 和 QStyledItemDelegate类继承。其中, QItemDelegate类由表示数据库中关系代理的QSqlRelationalDelegate类继承。


简单文件目录浏览器【简单示例】

简单实现一个文件目录浏览器。只需要编辑main.cpp文件在项目文件中即可。


  • main.cpp
#include "mainwindow.h"
#include <QApplication>
#include <QAbstractItemModel>
#include <QAbstractItemView>
#include <QItemSelectionModel>
#include <QDirModel>
#include <QTreeView>
#include <QListView>
#include <QTableView>
#include <QSplitter>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    //新建一个QDirModel对象,为数据访问做准备,此外还可以设置过滤器。
    //QDirmodel为访问本地文件系统提供数据模型,提供了新建、删除、创建目录等一系列与文件操作相关的函数。
    QDirModel model;
    /* 新建三种不同的View对象,以便文件目录可以以三种不同的方式显示 */
    QTreeView tree;
    QListView list;
    QTableView table;
    //调用setModel函数设置View对象的model为QDirmodel。
    tree.setModel(&model);
    list.setModel(&model);
    table.setModel(&model);
    //设置QTreeView对象的选择方式为多选方式。
    tree.setSelectionMode(QAbstractItemView::MultiSelection);
    //设置QListView对象与QTreeView对象使用相同的选择模型。
    list.setSelectionModel(tree.selectionModel());
    //设置QTableView对象与QTreeView对象使用相同的选择模型。
    table.setSelectionModel(tree.selectionModel());
    QObject::connect(&tree,SIGNAL(doubleClicked(QModelIndex)),&list,
                           SLOT(setRootIndex(QModelIndex)));
    //实现双机对象中某一目录时显示此目录下的所以文件和目录,需要连接QTreeView对象的doubleClicked信号
    //与QListView对象和QTableView对象的setRootIndex槽函数。
    QObject::connect(&tree,SIGNAL(doubleClicked(QModelIndex)),&table,
                           SLOT(setRootIndex(QModelIndex)));
    QSplitter *splitter = new QSplitter;
    splitter->addWidget(&tree);
    splitter->addWidget(&list);
    splitter->addWidget(&table);
    splitter->setWindowTitle(QObject::tr("Model/View"));
    splitter->show();
    //MainWindow w;
    //w.show();
    return a.exec();
}


  • 执行结果

20200319162027115.gif

模型(Model)

通过实现将数值代码转换为文字的模型来介绍使用自定义模型。此模型中保存了不同军中的各种武器。

在model中会用到以下item主要的角色:


常量 描述

Qt::DisplayRole 显示文字

Qt::DecorationRole 绘制装饰数据(通常是图标)

Qt::EditRole 在编辑器中编辑的数据

Qt::ToolTipRole 工具提示

Qt::StatusTipRole 状态栏提示

Qt::WhatsThisRole What’s This文字

Qt::SizeHintRole 尺寸提示

Qt::FontRole 默认代理的绘制使用的字体

Qt::TextAlignmentRole 默认代理的对齐方式

Qt::BackgroundRole 默认代理的背景画刷

Qt::ForegroundRole 默认代理的前景画刷

Qt::CheckStateRole 默认代理的检查框状态

Qt::UserRole 用户自定义的数据的起始位置

自定义模型【示例】

  • 项目结构

20200319163305829.png


  • main.cpp


#include "mainwindow.h"
#include <QApplication>
#include "modelex.h"
#include <QTableView>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    ModelEx modelEx;
    QTableView view;
    view.setModel(&modelEx);
    view.setWindowTitle(QObject::tr("modelEx"));
    view.resize(400,400);
    view.show();
    //MainWindow w;
    //w.show();
    return a.exec();
}


  • modelex.h
#ifndef MODELEX_H
#define MODELEX_H
#include <QAbstractTableModel>
#include <QVector>
#include <QMap>
#include <QStringList>
class ModelEx : public QAbstractTableModel
{
public:
    explicit ModelEx(QObject *parent=0);
    //虚函数声明          //(a)
    virtual int rowCount(const QModelIndex &parent=QModelIndex()) const;
    virtual int columnCount(const QModelIndex &parent=QModelIndex()) const;
    QVariant data(const QModelIndex &index, int role) const;
    QVariant headerData(int section, Qt::Orientation orientation, int role) const;
signals:
public slots:
private:
    QVector<short> army;
    QVector<short> weaponType;
    QMap<short,QString> armyMap;  //使用QMap数据结构保存“数值—文字”的映射
    QMap<short,QString> weaponTypeMap;
    QStringList  weapon;
    QStringList  header;
    void populateModel();   //完成表格数据的初始化填充
};
#endif // MODELEX_H


  • modelex.cpp
#include "modelex.h"
ModelEx::ModelEx(QObject *parent):QAbstractTableModel(parent)
{
    armyMap[1]=tr("空军");
    armyMap[2]=tr("海军");
    armyMap[3]=tr("陆军");
    armyMap[4]=tr("海军陆战队");
    weaponTypeMap[1]=tr("轰炸机");
    weaponTypeMap[2]=tr("战斗机");
    weaponTypeMap[3]=tr("航空母舰");
    weaponTypeMap[4]=tr("驱逐舰");
    weaponTypeMap[5]=tr("直升机");
    weaponTypeMap[6]=tr("坦克");
    weaponTypeMap[7]=tr("两栖攻击舰");
    weaponTypeMap[8]=tr("两栖战车");
    populateModel();
}
void ModelEx::populateModel()
{
    header<<tr("军种")<<tr("种类")<<tr("武器");
    army<<1<<2<<3<<4<<2<<4<<3<<1;
    weaponType<<1<<3<<5<<7<<4<<8<<6<<2;
    weapon<<tr("B-2")<<tr("尼米兹级")<<tr("阿帕奇")<<tr("黄蜂级")
            <<tr("阿利伯克级")<<tr("AAAV")<<tr("M1A1")<<tr("F-22");
}
int ModelEx::columnCount(const QModelIndex &parent) const
{  return 3;    }
int ModelEx::rowCount(const QModelIndex &parent) const
{
    return army.size();
}
QVariant ModelEx::data(const QModelIndex &index, int role) const
{
    if(!index.isValid())
        return QVariant();
    if(role==Qt::DisplayRole)    //(a)
    {
        switch(index.column())
        {
        case 0:
            return armyMap[army[index.row()]];
            break;
        case 1:
            return weaponTypeMap[weaponType[index.row()]];
            break;
        case 2:
            return weapon[index.row()];
        default:
            return QVariant();
        }
    }
    return QVariant();
}
QVariant ModelEx::headerData(int section, Qt::Orientation orientation, int role) const
{
    if(role==Qt::DisplayRole&&orientation==Qt::Horizontal)
           return header[section];
    return QAbstractTableModel::headerData(section,orientation,role);
}


  • 执行结果

20200319163305829.png

视图(View)

通过自定义的view实现一个对TableModel的表格数据进行显示的柱状图统计图示例。


表格数据显示【示例】

  • 项目结构


20200319164614181.png

  • main.cpp


#include "mainwindow.h"
#include <QApplication>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    return a.exec();
}


  • mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QStandardItemModel>
#include <QTableView>
#include <QMenuBar>
#include <QMenu>
#include <QAction>
#include <QSplitter>
#include "histogramview.h"
class MainWindow : public QMainWindow
{
    Q_OBJECT
public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();
    void createAction();
    void createMenu();
    void setupModel();
    void setupView();
    void openFile(QString);
public slots:
    void slotOpen();
private:
    QMenu *fileMenu;
    QAction *openAct;
    QStandardItemModel *model;
    QTableView *table;
    QSplitter *splitter;
    HistogramView *histogram;
};
#endif // MAINWINDOW_H


  • mainwindow.cpp
#include "mainwindow.h"
#include <QItemSelectionModel>
#include <QFileDialog>
#include <QFile>
#include <QTextStream>
#include <QStringList>
MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    createAction();
    createMenu();
    setupModel();
    setupView();
    setWindowTitle(tr("View Example"));
    resize(600,600);
}
MainWindow::~MainWindow()
{
}
void MainWindow::createAction()
{
    openAct = new QAction(tr("打开"),this);
    connect(openAct,SIGNAL(triggered()),this,SLOT(slotOpen()));
}
void MainWindow::createMenu()
{
    fileMenu = new QMenu(tr("文件"),this);
    fileMenu->addAction(openAct);
    menuBar()->addMenu(fileMenu);
}
void MainWindow::setupModel()
{
    model = new QStandardItemModel(4,4,this);
    model->setHeaderData(0,Qt::Horizontal,tr("部门"));
    model->setHeaderData(1,Qt::Horizontal,tr("男"));
    model->setHeaderData(2,Qt::Horizontal,tr("女"));
    model->setHeaderData(3,Qt::Horizontal,tr("退休"));
}
void MainWindow::setupView()
{
    /*
    table = new QTableView;   //新建一个QTableView对象
    table->setModel(model);   //为QTableView对象设置相同的Model
    QItemSelectionModel *selectionModel=new QItemSelectionModel(model);
                                    //(a)
    table->setSelectionModel(selectionModel);
    connect(selectionModel,SIGNAL(selectionChanged(QItemSelection, ItemSelection)),table,SLOT(selectionChanged(QItemSelection,QItemSelection)));          //(b)
    splitter = new QSplitter;
    splitter->setOrientation(Qt::Vertical);
    splitter->addWidget(table);
    setCentralWidget(splitter);
    */
    splitter = new QSplitter;
    splitter->setOrientation(Qt::Vertical);
    histogram = new HistogramView(splitter);        //新建一个HistogramView对象
    histogram->setModel(model);                     //为HistogramView对象设置相同的Model
    table = new QTableView;
    table->setModel(model);
    QItemSelectionModel *selectionModel=new QItemSelectionModel (model);
    table->setSelectionModel(selectionModel);
    histogram->setSelectionModel(selectionModel); //(a)
    splitter->addWidget(table);
    splitter->addWidget(histogram);
    setCentralWidget(splitter);
    connect(selectionModel,SIGNAL(selectionChanged(QItemSelection,QItemSelection)),table,SLOT(selectionChanged(QItemSelection,QItemSelection)));
    connect(selectionModel,SIGNAL(selectionChanged(QItemSelection,QItemSelection)),histogram,SLOT(selectionChanged(QItemSelection,QItemSelection)));        //(b)
}
void MainWindow::slotOpen()
{
    QString name;
    name = QFileDialog::getOpenFileName(this,"打开",".","histogram files (*.txt)");
    if (!name.isEmpty())
          openFile(name);
}
void MainWindow::openFile(QString path)
{
    if (!path.isEmpty())
    {
        QFile file(path);
         if (file.open(QFile::ReadOnly | QFile::Text))
         {
             QTextStream stream(&file);
             QString line;
             model->removeRows(0,model->rowCount(QModelIndex()),
                   QModelIndex());
             int row = 0;
             do
             {
                 line = stream.readLine();
                 if (!line.isEmpty())
                 {
                        model->insertRows(row, 1, QModelIndex());
                        QStringList pieces = line.split(",", QString
                            ::SkipEmptyParts);
                        model->setData(model->index(row, 0, QModelIndex()),
                            pieces.value(0));
                        model->setData(model->index(row, 1, QModelIndex()),
                            pieces.value(1));
                        model->setData(model->index(row, 2, QModelIndex()),
                            pieces.value(2));
                        model->setData(model->index(row,3, QModelIndex()),
                            pieces.value(3));
                        row++;
                 }
             } while (!line.isEmpty());
           file.close();
         }
    }
}


  • histogramview.h
#ifndef HISTOGRAMVIEW_H
#define HISTOGRAMVIEW_H
#include <QAbstractItemView>
#include <QItemSelectionModel>
#include <QRegion>
#include <QMouseEvent>
class HistogramView : public QAbstractItemView
{
    Q_OBJECT
public:
    HistogramView(QWidget *parent=0);
    //虚函数声明
    QRect visualRect(const QModelIndex &index)const;
    void scrollTo(const QModelIndex &index,ScrollHint hint= EnsureVisible);
    QModelIndex indexAt(const QPoint &point)const;
    //为selections赋初值
    void setSelectionModel(QItemSelectionModel *selectionModel);
    QRegion itemRegion(QModelIndex index);
    void paintEvent(QPaintEvent *);
    void mousePressEvent(QMouseEvent *event);
protected slots:
    void selectionChanged(const QItemSelection &selected,
          const QItemSelection &deselected);
    void dataChanged(const QModelIndex &topLeft,
          const QModelIndex &bottomRight);
protected:
    //虚函数声明
    QModelIndex moveCursor(QAbstractItemView::CursorAction cursorAction,
          Qt::KeyboardModifiers modifiers);
    int horizontalOffset()const;
    int verticalOffset()const;
    bool isIndexHidden(const QModelIndex &index)const;
    void setSelection(const QRect &rect,QItemSelectionModel:: SelectionFlags flags);//(f)
    QRegion visualRegionForSelection(const QItemSelection &selection) const;
private:
    QItemSelectionModel *selections;      //(g)
    QList<QRegion> MRegionList;       //(h)
    QList<QRegion> FRegionList;
    QList<QRegion> SRegionList;
};
#endif // HISTOGRAMVIEW_H


  • histogramview.cpp
#include "histogramview.h"
#include <QPainter>
HistogramView::HistogramView(QWidget *parent):QAbstractItemView(parent)
{
}
// paintEvent()函数具体完成柱状统计图绘制的工作
void HistogramView::paintEvent(QPaintEvent *)
{
    QPainter painter(viewport());     //(a)
    painter.setPen(Qt::black);
    int x0=40;
    int y0=250;
    /* 完成了x、y坐标轴的绘制,并标注坐标轴的变量 */
    //y坐标轴
    painter.drawLine(x0,y0,40,30);
    painter.drawLine(38,32,40,30);
    painter.drawLine(40,30,42,32);
    painter.drawText(20,30,tr("人数"));
    for(int i=1;i<5;i++)
    {
        painter.drawLine(-1,-i*50,1,-i*50);
        painter.drawText(-20,-i*50,tr("%1").arg(i*5));
    }
    //x 坐标轴
    painter.drawLine(x0,y0,540,250);
    painter.drawLine(538,248,540,250);
    painter.drawLine(540,250,538,252);
    painter.drawText(545,250,tr("部门"));
    int posD=x0+20;
    int row;
    for(row=0;row<model()->rowCount(rootIndex());row++)
    {
        QModelIndex index=model()->index(row,0,rootIndex());
        QString dep=model()->data(index).toString();
        painter.drawText(posD,y0+20,dep);
        posD+=50;
    }
    /* 完成了表格第1列数据的柱状统计图的绘制 */
    //男
    int posM=x0+20;
    MRegionList.clear();
    for(row=0;row<model()->rowCount(rootIndex());row++)
    {
        QModelIndex index=model()->index(row,1,rootIndex());
        int male=model()->data(index).toDouble();
        int width=10;
        if(selections->isSelected(index))   //(b)
            painter.setBrush(QBrush(Qt::blue,Qt::Dense3Pattern));
        else
            painter.setBrush(Qt::blue);
        painter.drawRect(QRect(posM,y0-male*10,width,male*10));//(c)
        QRegion regionM(posM,y0-male*10,width,male*10);
        MRegionList.insert(row,regionM);            //(d)
        posM+=50;
    }
    /* 完成了表格第2列数据的柱状统计图的绘制 */   //(e)
    //女
    int posF=x0+30;
    FRegionList.clear();
    for(row=0;row<model()->rowCount(rootIndex());row++)
    {
        QModelIndex index=model()->index(row,2,rootIndex());
        int female=model()->data(index).toDouble();
        int width=10;
        if(selections->isSelected(index))
            painter.setBrush(QBrush(Qt::red,Qt::Dense3Pattern));
        else
            painter.setBrush(Qt::red);
        painter.drawRect(QRect(posF,y0-female*10,width,female*10));
        QRegion regionF(posF,y0-female*10,width,female*10);
        FRegionList.insert(row,regionF);
        posF+=50;
    }
    /* 完成了表格第3列数据的柱状统计图的绘制 */   //(f)
    //退休
    int posS=x0+40;
    SRegionList.clear();
    for(row=0;row<model()->rowCount(rootIndex());row++)
    {
        QModelIndex index=model()->index(row,3,rootIndex());
        int retire=model()->data(index).toDouble();
        int width=10;
        if(selections->isSelected(index))
            painter.setBrush(QBrush(Qt::green,Qt::Dense3Pattern));
        else
            painter.setBrush(Qt::green);
        painter.drawRect(QRect(posS,y0-retire*10,width,retire*10));
        QRegion regionS(posS,y0-retire*10,width,retire*10);
        SRegionList.insert(row,regionS);
        posS+=50;
    }
}
void HistogramView::dataChanged(const QModelIndex &topLeft,
       const QModelIndex &bottomRight)
{
    QAbstractItemView::dataChanged(topLeft,bottomRight);
    viewport()->update();
}
void HistogramView::setSelectionModel(QItemSelectionModel *selectionModel)
{
    selections=selectionModel;
}
void HistogramView::selectionChanged(const QItemSelection &selected,
      const QItemSelection &deselected)
{
    viewport()->update();
}
void HistogramView::mousePressEvent(QMouseEvent *event)
{
    QAbstractItemView::mousePressEvent(event);
    setSelection(QRect(event->pos().x(),event->pos().y(),1,1),QItemSelectionModel::SelectCurrent);
}
void HistogramView::setSelection(const QRect &rect,QItemSelectionModel::SelectionFlags flags)
{
    int rows = model()->rowCount(rootIndex());    //获取总行数
    int columns = model()->columnCount(rootIndex());  //获取总列数
    QModelIndex selectedIndex;
    for (int row=0; row<rows; ++row)
    {
        for (int column=1; column<columns; ++column)
        {
            QModelIndex index=model()->index(row,column,rootIndex());
            QRegion region=itemRegion(index);
            if (!region.intersected(rect).isEmpty())
                selectedIndex = index;
        }
    }
    if(selectedIndex.isValid())
        selections->select(selectedIndex,flags);
    else
    {
        QModelIndex noIndex;
        selections->select(noIndex,flags);
    }
}
QModelIndex HistogramView::indexAt(const QPoint &point)const
{
    QPoint newPoint(point.x(),point.y());
    QRegion region;
    // 男 列
    foreach(region,MRegionList)
    {
        if (region.contains(newPoint))
        {
            int row = MRegionList.indexOf(region);
            QModelIndex index = model()->index(row,1,rootIndex());
            return index;
        }
    }
    // 女 列
    foreach(region,FRegionList)
    {
        if (region.contains(newPoint))
        {
            int row = FRegionList.indexOf(region);
            QModelIndex index = model()->index(row,2,rootIndex());
            return index;
        }
    }
    // 合计 列
    foreach(region,SRegionList)
    {
        if (region.contains(newPoint))
        {
            int row = SRegionList.indexOf(region);
            QModelIndex index = model()->index(row,3,rootIndex());
            return index;
        }
    }
    return QModelIndex();
}
QRect HistogramView::visualRect(const QModelIndex &index)const{}
void HistogramView::scrollTo(const QModelIndex &index,ScrollHint){}
QModelIndex HistogramView::moveCursor(QAbstractItemView::CursorAction cursorAction, Qt::KeyboardModifiers modifiers){}
int HistogramView::horizontalOffset()const{}
int HistogramView::verticalOffset()const{}
bool HistogramView::isIndexHidden(const QModelIndex &index)const{}
QRegion HistogramView::visualRegionForSelection(const QItemSelection & selection)const{}
QRegion HistogramView::itemRegion(QModelIndex index)
{
    QRegion region;
    if (index.column() == 1)  //男
        region = MRegionList[index.row()];
    if (index.column() == 2)  //女
        region = FRegionList[index.row()];
    if (index.column() == 3)  //退休
        region = SRegionList[index.row()];
    return region;
}


  • 执行结果

20200319164520436.gif

代理(Delegate)

利用Delegate设计表格控件。


利用Delegate设计表格控件【示例】

  • 项目结构

2020031916575199.png

  • main.cpp
#include "mainwindow.h"
#include <QApplication>
#include <QStandardItemModel>
#include <QTableView>
#include <QFile>
#include <QTextStream>
#include "datedelegate.h"
#include "combodelegate.h"
#include "spindelegate.h"
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QStandardItemModel model(4,4);
    QTableView tableView;
    tableView.setModel(&model);
    DateDelegate dateDelegate;
    tableView.setItemDelegateForColumn(1,&dateDelegate);
    ComboDelegate comboDelegate;
    tableView.setItemDelegateForColumn(2,&comboDelegate);
    SpinDelegate spinDelegate;
    tableView.setItemDelegateForColumn(3,&spinDelegate);
    model.setHeaderData(0,Qt::Horizontal,QObject::tr("姓名"));
    model.setHeaderData(1,Qt::Horizontal,QObject::tr("生日"));
    model.setHeaderData(2,Qt::Horizontal,QObject::tr("职业"));
    model.setHeaderData(3,Qt::Horizontal,QObject::tr("收入"));
    QFile file("test.txt");
    if(file.open(QFile::ReadOnly|QFile::Text))
    {
        QTextStream stream(&file);
        QString line;
        model.removeRows(0,model.rowCount(QModelIndex()),QModelIndex());
        int row =0;
        do{
               line = stream.readLine();
               if(!line.isEmpty())
               {
                   model.insertRows(row,1,QModelIndex());
                   QStringList pieces = line.split(",",QString::SkipEmptyParts);
                   model.setData(model.index(row,0,QModelIndex()), pieces
                         .value(0));
                   model.setData(model.index(row,1,QModelIndex()), pieces
                         .value(1));
                   model.setData(model.index(row,2,QModelIndex()), pieces
                         .value(2));
                   model.setData(model.index(row,3,QModelIndex()), pieces
                         .value(3));
                   row++;
               }
        }while(!line.isEmpty());
        file.close();
    }
    tableView.setWindowTitle(QObject::tr("Delegate"));
    tableView.show();
    //MainWindow w;
    //w.show();
    return a.exec();
}


  • spindelegate.h
#ifndef SPINDELEGATE_H
#define SPINDELEGATE_H
#include <QItemDelegate>
class SpinDelegate : public QItemDelegate
{
    Q_OBJECT
public:
    SpinDelegate(QObject *parent = 0);
    QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex  &index) const;
    void setEditorData(QWidget *editor, const QModelIndex &index) const;
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const;
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const;
};
#endif // SPINDELEGATE_H


  • spindelegate.cpp
#include "spindelegate.h"
#include <QSpinBox>
SpinDelegate::SpinDelegate(QObject *parent):QItemDelegate(parent)
{
}
QWidget *SpinDelegate::createEditor(QWidget *parent,const QStyleOptionViewItem &/*option*/,const QModelIndex &/*index*/) const
{
    QSpinBox *editor = new QSpinBox(parent);
    editor->setRange(0,10000);
    editor->installEventFilter(const_cast<SpinDelegate*>(this));
    return editor;
}
void SpinDelegate::setEditorData(QWidget *editor,const QModelIndex &index) const
{
    int value =index.model()->data(index).toInt();
    QSpinBox *box = static_cast<QSpinBox*>(editor);
    box->setValue(value);
}
void SpinDelegate::setModelData(QWidget *editor, QAbstractItemModel *model,const QModelIndex &index) const
{
    QSpinBox *box = static_cast<QSpinBox*>(editor);
    int value = box->value();
    model->setData(index,value);
}
void SpinDelegate::updateEditorGeometry(QWidget *editor,
const QStyleOptionViewItem &option, const QModelIndex &/*index*/) const
{
    editor->setGeometry(option.rect);
}


  • datedelegate.h
#ifndef DATEDELEGATE_H
#define DATEDELEGATE_H
#include <QItemDelegate>
class DateDelegate : public QItemDelegate
{
    Q_OBJECT
public:
    DateDelegate(QObject *parent = 0);
    QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem & option, const QModelIndex &index) const;    //(a)
    void setEditorData(QWidget *editor, const QModelIndex &index) const;              //(b)
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const;  //将Delegate中对数据的改变更新至Model中
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem & option, const QModelIndex &index) const;  //更新控件区的显示
};
#endif // DATEDELEGATE_H
  • datedelegate.cpp
#include "datedelegate.h"
#include <QDateTimeEdit>
DateDelegate::DateDelegate(QObject *parent):QItemDelegate(parent)
{
}
QWidget *DateDelegate::createEditor(QWidget *parent,const QStyleOptionViewItem &/*option*/,const QModelIndex &/*index*/) const
{
    QDateTimeEdit *editor = new QDateTimeEdit(parent);  //(a)
    editor->setDisplayFormat("yyyy-MM-dd");     //(b)
    editor->setCalendarPopup(true);       //(c)
    editor->installEventFilter(const_cast<DateDelegate*>(this));
                                                            //(d)
    return editor;
}
void DateDelegate::setEditorData(QWidget *editor,const QModelIndex &index) const
{
   QString dateStr= index.model()->data(index).toString();  //(a)
   QDate date = QDate::fromString(dateStr,Qt::ISODate);  //(b)
   QDateTimeEdit *edit=static_cast<QDateTimeEdit*>(editor); //(c)
   edit->setDate(date);                                     //设置控件的显示数据
}
void DateDelegate::setModelData(QWidget *editor,QAbstractItemModel *model, const QModelIndex &index) const
{
    QDateTimeEdit *edit=static_cast<QDateTimeEdit*>(editor);//(a)
    QDate date = edit->date();        //(b)
    model->setData(index,QVariant(date.toString(Qt::ISODate)));//(c)
}
void DateDelegate::updateEditorGeometry(QWidget *editor,const QStyleOptionViewItem &option,const QModelIndex &index) const
{
    editor->setGeometry(option.rect);
}


  • combodelegate.h
#ifndef COMBODELEGATE_H
#define COMBODELEGATE_H
#include <QItemDelegate>
class ComboDelegate : public QItemDelegate
{
    Q_OBJECT
public:
    ComboDelegate(QObject *parent = 0);
    QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const;
    void setEditorData(QWidget *editor, const QModelIndex &index) const;
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const;
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const;
};
#endif // COMBODELEGATE_H


  • combodelegate.cpp
#include "combodelegate.h"
#include <QComboBox>
ComboDelegate::ComboDelegate(QObject *parent):QItemDelegate(parent)
{
}
QWidget *ComboDelegate::createEditor(QWidget *parent,const QStyleOptionViewItem &/*option*/,const QModelIndex &/*index*/) const
{
    QComboBox *editor = new QComboBox(parent);
    editor->addItem("工人");
    editor->addItem("农民");
    editor->addItem("医生");
    editor->addItem("律师");
    editor->addItem("军人");
    editor->installEventFilter(const_cast<ComboDelegate*>(this));
    return editor;
}
void ComboDelegate::setEditorData(QWidget *editor,const QModelIndex &index) const
{
    QString str =index.model()->data(index).toString();
    QComboBox *box = static_cast<QComboBox*>(editor);
    int i=box->findText(str);
    box->setCurrentIndex(i);
}
void ComboDelegate::setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const
{
    QComboBox *box = static_cast<QComboBox*>(editor);
    QString str = box->currentText();
    model->setData(index,str);
}
void ComboDelegate::updateEditorGeometry(QWidget *editor,
const QStyleOptionViewItem &option, const QModelIndex &/*index*/) const
{
    editor->setGeometry(option.rect);
}


  • 执行结果

20200319165725516.gif

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