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我想封裝表視圖行爲，並開始將表視圖標題信號連接到子類中定義的表視圖插槽。我可以在沒有繼承的情況下獲得我正在尋找的行爲，但是這會破壞目的。當我嘗試子類化時，會遇到可怕的「沒有匹配的函數調用來連接，所有組件最終都是QObject，所以我認爲這不是問題（但是，那麼也許這就是問題所在）。我連接到'hideColumn（）'，但我最終想連接到我自己的插槽（例如'my_sectionClicked（int）'。Qt子類化和「沒有匹配函數的調用連接」
下面的代碼是從「C++ GUI Programming with Qt的4" ，由茉莉布蘭切特和Mark Summerfield的不同之處了 「MyTableView」 另外，我做。
MyTableView.h
#ifndef MYTABLEVIEW_HPP
#define MYTABLEVIEW_HPP
#include <QTableView>
class MyTableView : public QTableView
{
Q_OBJECT
public:
explicit MyTableView(QWidget *parent = 0);
public slots:
void my_sectionClicked(int logicalIndex);
private slots:
public:
private:
QHeaderView *m_rowHeader;
};
#endif // MYTABLEVIEW_HPP
MyTableV iew.cpp
// Qt Includes
#include <QDebug>
#include <QMenu>
// Local Includes
#include "MyTableView.h"
MyTableView::MyTableView(QWidget *parent) : QTableView(parent)
{
m_rowHeader = horizontalHeader();
connect(m_rowHeader, SIGNAL(sectionClicked(int)), this, SLOT(hideColumn(int)));
}
void MyTableView::my_sectionClicked(int logicalIndex)
{
qDebug().nospace() << "Column " << logicalIndex << " selected." << "\n";
}
currencymodel.h
#ifndef CURRENCYMODEL_H
#define CURRENCYMODEL_H
#include <QAbstractTableModel>
#include <QMap>
class CurrencyModel : public QAbstractTableModel
{
public:
CurrencyModel(QObject *parent = 0);
void setCurrencyMap(const QMap<QString, double> &map);
int rowCount(const QModelIndex &parent) const;
int columnCount(const QModelIndex &parent) const;
QVariant data(const QModelIndex &index, int role) const;
QVariant headerData(int section, Qt::Orientation orientation,
int role) const;
private:
QString currencyAt(int offset) const;
QMap<QString, double> currencyMap;
};
#endif
currencymodel.cpp
#include <QtCore>
#include "currencymodel.h"
CurrencyModel::CurrencyModel(QObject *parent)
: QAbstractTableModel(parent)
{
}
void CurrencyModel::setCurrencyMap(const QMap<QString, double> &map)
{
currencyMap = map;
reset(); // Forces views to refresh data
}
int CurrencyModel::rowCount(const QModelIndex & /* parent */) const
{
return currencyMap.count();
}
int CurrencyModel::columnCount(const QModelIndex & /* parent */) const
{
return currencyMap.count();
}
QVariant CurrencyModel::data(const QModelIndex &index, int role) const
{
if (!index.isValid())
return QVariant();
if (role == Qt::TextAlignmentRole)
{
return int(Qt::AlignRight | Qt::AlignVCenter);
}
else if (role == Qt::DisplayRole)
{
QString rowCurrency = currencyAt(index.row());
QString columnCurrency = currencyAt(index.column());
if (currencyMap.value(rowCurrency) == 0.0)
return "####";
double amount = currencyMap.value(columnCurrency)
/currencyMap.value(rowCurrency);
return QString("%1").arg(amount, 0, 'f', 4);
}
return QVariant();
}
QVariant CurrencyModel::headerData(int section,
Qt::Orientation /* orientation */,
int role) const
{
if (role != Qt::DisplayRole)
return QVariant();
return currencyAt(section);
}
QString CurrencyModel::currencyAt(int offset) const
{
return (currencyMap.begin() + offset).key();
}
mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QtGui>
#include "MyTableView.h"
#include "currencymodel.h"
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow();
protected:
private slots:
void on_sectionClicked(int locicalIndex);
private:
QMap<QString, double> currencyMap;
CurrencyModel currencyModel;
QTableView tableView;
QHeaderView *m_rowHeader;
};
#endif
mainwindow.cpp
#include <iostream>
#include "mainwindow.h"
MainWindow::MainWindow()
{
currencyMap.insert("AUD", 1.3259);
currencyMap.insert("CHF", 1.2970);
currencyMap.insert("CZK", 24.510);
currencyMap.insert("DKK", 6.2168);
currencyMap.insert("EUR", 0.8333);
currencyMap.insert("GBP", 0.5661);
currencyMap.insert("HKD", 7.7562);
currencyMap.insert("JPY", 112.92);
currencyMap.insert("NOK", 6.5200);
currencyMap.insert("NZD", 1.4697);
currencyMap.insert("SEK", 7.8180);
currencyMap.insert("SGD", 1.6901);
currencyMap.insert("USD", 1.0000);
currencyModel.setCurrencyMap(currencyMap);
/*
THIS WORKS!!!
m_rowHeader = tableView.horizontalHeader();
connect(m_rowHeader, SIGNAL(sectionClicked(int)),
&(tableView), SLOT(hideColumn(int)));
*/
tableView.setModel(¤cyModel);
tableView.setAlternatingRowColors(true);
tableView.setWindowTitle(QObject::tr("Currencies"));
tableView.show();
}
void MainWindow::on_sectionClicked(int logicalIndex)
{
qDebug().nospace() << "Column " << logicalIndex << " selected." << "\n";
}
的main.cpp
#include "mainwindow.h"
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
MainWindow mainWin;
return app.exec();
}
我得到的錯誤是：
g++ -c -pipe -O2 -Wall -W -D_REENTRANT -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -DQT_SHARED -I/opt/QtSDK/Desktop/Qt/4.8.1/gcc/mkspecs/default -I. -I/opt/QtSDK/Desktop/Qt/4.8.1/gcc/include/QtCore -I/opt/QtSDK/Desktop/Qt/4.8.1/gcc/include/QtGui -I/opt/QtSDK/Desktop/Qt/4.8.1/gcc/include -I. -I. -o MyTableView.o MyTableView.cpp
MyTableView.cpp: In constructor ‘MyTableView::MyTableView(QWidget*)’:
MyTableView.cpp:11: error: no matching function for call to ‘MyTableView::connect(QHeaderView*&, const char [21], MyTableView* const, const char [17])’
/opt/QtSDK/Desktop/Qt/4.8.1/gcc/include/QtCore/qobject.h:204: note: candidates are: static bool QObject::connect(const QObject*, const char*, const QObject*, const char*, Qt::ConnectionType)
/opt/QtSDK/Desktop/Qt/4.8.1/gcc/include/QtCore/qobject.h:217: note: static bool QObject::connect(const QObject*, const QMetaMethod&, const QObject*, const QMetaMethod&, Qt::ConnectionType)
/opt/QtSDK/Desktop/Qt/4.8.1/gcc/include/QtCore/qobject.h:337: note: bool QObject::connect(const QObject*, const char*, const char*, Qt::ConnectionType) const
make: *** [MyTableView.o] Error 1
my_sectionClicked在哪裏使用？ –
tl; dr。只發布相關的代碼。 – cmannett85
@VaibhavDesai有一次，與'hideColumn（int）'的連接是到'my_sectionClicked（int）'的連接。我將它改爲現有的Qt插槽，作爲排除故障時的一個過程。 –