Qt C++错误--没有调用'QString::QString(KeySequence)‘的匹配函数

Question

在用C++编写的GUI项目中，我使用了QT4.8.4。现在，我合并到QT5.7版本。经过长时间的代码调整之后，我终于打开了GUI。但是，当我运行我的计算代码时，我仍然会得到以下错误：

调用'QString::QString(KeySequence)'的无匹配函数

在以下几行：

  action = popup->addAction(EnhTableWidget::tr("&Copy") + QLatin1Char('\t') + QString(QKeySequence(QKeySequence::Copy)));
  ...
  action = popup->addAction(EnhTableWidget::tr("Delete") + QLatin1Char('\t') + QString(QKeySequence(QKeySequence::Delete)));
  ...
  action = popup->addAction(EnhTableWidget::tr("Select All") + QLatin1Char('\t') + QString(QKeySequence(QKeySequence::SelectAll)));

QKeySequence的使用似乎是错误的。从Qt站点我看不出问题所在。

怎么啦？

这是我代码的一部分：

 #include "EnhTableWidget.h"
 #include <QKeyEvent>
 #include <QApplication>
 #include <QClipboard>
 #include <QHeaderView>
 #include <QKeySequence>
 #include <QAction>

 EnhTableWidget::EnhTableWidget(QWidget *parent) :
  QTableWidget(parent)
 {}


 void EnhTableWidget::keyPressEvent(QKeyEvent *event)
 {
       if ( event->matches(QKeySequence::Copy) )
        copy();
       else if ( event->matches(QKeySequence::Delete) || event->key() == Qt::Key_Backspace )
        deleteSelected();
       else if ( event->matches(QKeySequence::SelectAll) )
        selectAll();
       else
        QTableWidget::keyPressEvent(event);
 }


QMenu *EnhTableWidget::createStandardContextMenu()
  {
    QMenu *popup = new QMenu(this);
    popup->setObjectName(QLatin1String("qt_edit_menu"));
    QAction *action = 0;

  #ifndef QT_NO_CLIPBOARD

    action = popup->addAction(EnhTableWidget::tr("&Copy") + QLatin1Char('\t') + QString(QKeySequence(QKeySequence::Copy)));
    action->setEnabled(!selectionModel()->selectedIndexes().isEmpty());
    connect(action, SIGNAL(triggered()), SLOT(copy()));

  #endif

    action = popup->addAction(EnhTableWidget::tr("Delete") + QLatin1Char('\t') + QString(QKeySequence(QKeySequence::Delete)));
    action->setEnabled(isEnabled() && !selectionModel()->selectedIndexes().isEmpty());
    connect(action, SIGNAL(triggered()), this, SLOT(deleteSelected()));

        if (!popup->isEmpty())
              popup->addSeparator();

    action = popup->addAction(EnhTableWidget::tr("Select All") + QLatin1Char('\t') + QString(QKeySequence(QKeySequence::SelectAll)));
    action->setEnabled(isEnabled());
    connect(action, SIGNAL(triggered()), SLOT(selectAll()));

  return popup;
 }

Answer 1

QString没有一个以QKeySequence作为参数的构造函数。你必须使用QKeySequence::toString。

action = popup->addAction(tr("&Copy") + QLatin1Char('\t') + QKeySequence(QKeySequence::Copy).toString());