(C++) QTableViewExample5

 

 

QTableView example 5: simple custom data is a QTableView example.

 

• View a screenshot of 'QTableViewExample5' (png)
• Download the Qt Creator project 'QTableViewExample5' (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: ./CppQTableViewExample5/CppQTableViewExample5.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 HEADERS  += qtdialog.h FORMS    += qtdialog.ui

 

 

 

 

 

./CppQTableViewExample5/qtdialog.h

 

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

 

 

 

 

 

./CppQTableViewExample5/qtdialog.cpp

 

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#include "qtdialog.h" #include <cassert> #include <iostream> #include <stdexcept> #include <boost/numeric/conversion/cast.hpp> #include <QHeaderView> #include <QStandardItemModel> #include "ui_qtdialog.h" ///A simple custom data type ///For now, its just contains a std::vector<std::string> struct MyDataTable {   MyDataTable() : data(CreateTable())  {}   std::vector<std::string> data;   static const std::vector<std::string> CreateTable()   {     return     {       "Black",       "Blue",       "Cyan",       "Green",       "Magenta"       "Red",       "White",       "Yellow",     };   } }; struct MyModel : public QStandardItemModel {   MyModel(QObject *parent = 0)     : QStandardItemModel(         0, //rows, will become 8         1, //columns, only 1 for now         parent       ),       m_data(MyDataTable())   {     setColumnCount(1); //Only 1 for now     setHeaderData(0,Qt::Horizontal,"Color");     const int n_rows = boost::numeric_cast<int>(m_data.data.size());     for (int i=0; i!=n_rows; ++i)     {       QList<QStandardItem*> items;       //Add text       {         QStandardItem * const item = new QStandardItem;         item->setCheckable(false); //NO CHECKBOX!         items.push_back(item);       }       //Only have one column for now       assert(this->columnCount() == items.size());       this->appendRow(items);     }     assert(this->rowCount() == boost::numeric_cast<int>(m_data.data.size()));   }   ///Implement virtual member function   QVariant 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());     assert(index.row() < boost::numeric_cast<int>(m_data.data.size()));     assert(index.column() < 1);     const std::string& row = m_data.data[ index.row() ];     switch (index.column())     {       case 0:         //Only 1 column for now         return QString(row.c_str());       default:         assert(!"Should not get here");         throw std::logic_error("MyModel::data");     }   }   ///Implement virtual member function   bool setData(const QModelIndex &index, const QVariant &value, int /*role = Qt::EditRole*/)   {     assert(index.isValid());     assert(index.row() < boost::numeric_cast<int>(m_data.data.size()));     assert(index.column() < 1);     std::string& row = m_data.data[ index.row() ];     switch (index.column())     {       case 0:         //Only 1 column for now         row = value.toString().toStdString(); break;       default:         assert(!"Should not get here");         throw std::logic_error("MyModel::setData");     }     //Allows other views to synchronize on this model update     emit dataChanged(index,index); //From C++ GUI programming with Qt 4, 2nd edition     return false;   }   private:   ///My custom data type   MyDataTable m_data; }; QtDialog::QtDialog(QWidget *parent) :   QDialog(parent),   ui(new Ui::QtDialog),   m_model(new MyModel(this)) {   ui->setupUi(this);   ui->table->setModel(m_model);   assert(ui->table->model());   assert(m_model);   assert(ui->table->model() == m_model);   //Only one column for now   ui->table->setColumnWidth(0,175); } QtDialog::~QtDialog() {   delete ui; }

 

 

 

 

 

./CppQTableViewExample5/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(); }