(C++) QTableViewExample7

 

 

QTableView example 7: two views on one model with a custom data type is a QTableView example.

 

• View a screenshot of 'QTableViewExample7' (png)
• Download the Qt Creator project 'QTableViewExample7' (zip)

Technical facts

 

Application type(s)

• Desktop application

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• GUI application

C++ standard:

• C++11

Compiler(s):

• G++ 4.9.2

Libraries used:

• Qt: version 5.4.1 (32 bit)
• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppQTableViewExample7/CppQTableViewExample7.pro

 

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QT       += core gui greaterThan(QT_MAJOR_VERSION, 4): QT += widgets QMAKE_CXXFLAGS += -Wall -Wextra -Werror TEMPLATE = app QMAKE_CXXFLAGS += -std=c++11 SOURCES += \     qtdialog.cpp \     qtmain.cpp \     mydata.cpp \     mymodel.cpp HEADERS  += qtdialog.h \     mydata.h \     mymodel.h FORMS    += qtdialog.ui

 

 

 

 

 

./CppQTableViewExample7/mydata.h

 

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#ifndef MYDATA_H #define MYDATA_H #include <boost/numeric/ublas/matrix.hpp> ///Plain interface to a matrix struct MyData {   MyData(const int n_rows = 4, const int n_cols = 3);   double Get(const int row, const int col) const;   int GetColCount() const;   int GetRowCount() const;   void Set(const int row, const int col, const double value);   private:   boost::numeric::ublas::matrix<double> m_v; }; #endif // MYDATA_H

 

 

 

 

 

./CppQTableViewExample7/mydata.cpp

 

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#include "mydata.h" #include <cassert> #include <boost/numeric/conversion/cast.hpp> MyData::MyData(const int n_rows, const int n_cols)   : m_v(n_rows,n_cols) {   for (int row = 0; row!=n_rows; ++row)   {     const double denominator = boost::numeric_cast<double>(row + 1);     for (int col = 0; col!=n_cols; ++col)     {       const double numerator = boost::numeric_cast<double>(col + 1);       m_v(row,col) = numerator / denominator;     }   } } double MyData::Get(const int row, const int col) const {   assert(row < boost::numeric_cast<int>(m_v.size1()));   assert(col < boost::numeric_cast<int>(m_v.size2()));   return m_v(row,col); } int MyData::GetColCount() const {   return boost::numeric_cast<int>(m_v.size2()); } int MyData::GetRowCount() const {   return boost::numeric_cast<int>(m_v.size1()); } void MyData::Set(const int row, const int col, const double value) {   assert(row < boost::numeric_cast<int>(m_v.size1()));   assert(col < boost::numeric_cast<int>(m_v.size2()));   m_v(row,col) = value; }

 

 

 

 

 

./CppQTableViewExample7/mymodel.h

 

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#ifndef MYMODEL_H #define MYMODEL_H #include <QAbstractTableModel> #include "mydata.h" //I did not use QStandardItemModel because I did not work with QStandardItem struct MyModel : public QAbstractTableModel {   MyModel(QObject *parent = 0);   //Must be defined from ABC   QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const;   ///These flags are needed to allow editing   Qt::ItemFlags flags(const QModelIndex &index) const;   ///Working with the raw data   MyData& GetData() { return m_data; }   const MyData& GetData() const { return m_data; }   ///Needed for editable data   bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole);   ///Must be defined from ABC   int rowCount(const QModelIndex &parent = QModelIndex()) const;   ///Must be defined from ABC   int columnCount(const QModelIndex &parent = QModelIndex()) const;   private:   ///The raw data   MyData m_data; }; #endif // MYMODEL_H

 

 

 

 

 

./CppQTableViewExample7/mymodel.cpp

 

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#include "mymodel.h" #include <cassert> #include <boost/lexical_cast.hpp> MyModel::MyModel(QObject *parent)   : QAbstractTableModel(parent) { } QVariant MyModel::data(const QModelIndex &index, int role) const {   //Removing this line will cause checkboxes to appear   if (role != Qt::EditRole &&  role != Qt::DisplayRole) return QVariant();   assert(index.isValid());   return m_data.Get(index.row(),index.column()); } Qt::ItemFlags MyModel::flags(const QModelIndex &) const {   return     Qt::ItemIsSelectable   | Qt::ItemIsEditable   | Qt::ItemIsDragEnabled   | Qt::ItemIsDropEnabled   | Qt::ItemIsEnabled; } int MyModel::rowCount(const QModelIndex &) const {   return m_data.GetRowCount(); } int MyModel::columnCount(const QModelIndex &) const {   return m_data.GetColCount(); } bool MyModel::setData(const QModelIndex &index, const QVariant &value, int /* role */) {   m_data.Set(index.row(),index.column(),value.toDouble());   ///This line below is needed to let the two views synchronize   emit dataChanged(index,index);   //Editing succeeded!   return true; }

 

 

 

 

 

./CppQTableViewExample7/qtdialog.h

 

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#ifndef QTDIALOG_H #define QTDIALOG_H #include <QDialog> namespace Ui {   class QtDialog; } class QtDialog : public QDialog {   Q_OBJECT    public:   explicit QtDialog(QWidget *parent = 0);   ~QtDialog();    private slots: private:   Ui::QtDialog *ui; }; #endif // QTDIALOG_H

 

 

 

 

 

./CppQTableViewExample7/qtdialog.cpp

 

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#include "qtdialog.h" #include <cassert> #include "mymodel.h" #include "ui_qtdialog.h" QtDialog::QtDialog(QWidget *parent) :   QDialog(parent),   ui(new Ui::QtDialog) {   ui->setupUi(this);   MyModel * const model = new MyModel(this);   assert(model);   ui->table_left->setModel(model);   ui->table_right->setModel(model);   assert(ui->table_left->model());   assert(ui->table_right->model());   assert(ui->table_left->model() == model);   assert(ui->table_right->model() == model); } QtDialog::~QtDialog() {   delete ui; }

 

 

 

 

 

./CppQTableViewExample7/qtmain.cpp

 

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