Question

我正在学习如何使用Qt进行C ++ GUI编程，由于一个奇怪的错误，我无法编译项目。

我收到以下错误消息：

error: out-of-line definition of 'FindDialog' does not match any declaration in 'FindDialog'

但我不明白为什么它说FindDialog类的定义和实现完全匹配。这是.h和.cpp文件的代码。我希望有人能告诉我错误在哪里以及如何解决。

.h文件：

#ifndef FINDDIALOG_H
#define FINDDIALOG_H

#include <QDialog>

class QCheckBox;
class QLabel;
class QLineEdit;
class QPushButton;

class FindDialog : public QDialog
{
    Q_OBJECT

public:
    FindDialog(QWidget *parent = 0);

signals:
    void findNext (const QString &str, Qt::CaseSensitivity cs);
    void findPrevious (const QString &str, Qt::CaseSensitivity cs);

private slots:
    void findClicked ();
    void enableFindButton (const QString &text);

private:
    QLabel *label;
    QLineEdit *lineEdit;
    QCheckBox *caseCheckBox;
    QCheckBox *backwardCheckBox;
    QPushButton *findButton;
    QPushButton *closeButton;
};

#endif // FINDDIALOG_H

.cpp文件：

#include "finddialog.h"

#include <QDialog>
#include <QLabel>
#include <QPushButton>
#include <QLineEdit>
#include <QCheckBox>
#include <QHBoxLayout>
#include <QVBoxLayout>

FindDialog::FindDialog (QDialog *parent) : QDialog(parent)
{
    label = new QLabel(tr("Find &what:"));
    lineEdit = new QLineEdit;
    label->setBuddy(lineEdit);

    caseCheckBox = new QCheckBox(tr("Match &case"));
    backwardCheckBox = new QCheckBox(tr("Search &backward"));

    findButton = new QPushButton(tr("&Find:"));
    findButton->setDefault(true);
    findButton->setEnabled(false);

    closeButton = new QPushButton(tr("Close"));

    connect(lineEdit, SIGNAL(textChanged(const QString &)),
            this, SLOT(enableFindButton(const QString &)));
    connect(findButton, SIGNAL(clicked()),
            this, SLOT(findClicked()));
    connect(closeButton, SIGNAL(clicked()),
            this, SLOT(close()));

    QHBoxLayout *topLeftLayout = new QHBoxLayout;
    topLeftLayout->addWidget(label);
    topLeftLayout->addWidget(lineEdit);

    QVBoxLayout *leftLayout = new QVBoxLayout;
    leftLayout->addLayout(topLeftLayout);
    leftLayout->addWidget(caseCheckBox);
    leftLayout->addWidget(backwardCheckBox);

    QVBoxLayout *rightLayout = new QVBoxLayout;
    rightLayout->addWidget(findButton);
    rightLayout->addWidget(closeButton);
    rightLayout->addStretch();

    QHBoxLayout *mainLayout = new QHBoxLayout;
    mainLayout->addLayout(leftLayout);
    mainLayout->addLayout(rightLayout);
    setLayout(mainLayout);

    setWindowTitle(tr("Find"));
    setFixedHeight(sizeHint().height());
}

void FindDialog::findClicked ()
{
    QString text = lineEdit->text();
    Qt::CaseSensitivity cs =
            caseCheckBox->isChecked() ? Qt::CaseSensitive : Qt::CaseInsensitive;

    if (backwardCheckBox->isChecked())
        emit findPrevious(text, cs);
    else
        emit findNext(text, cs);
}

void FindDialog::enableFindButton (const QString &text)
{
    findButton->setEnabled(!text.isEmpty());
}

Answer 1

您的构造函数声明为FindDialog(QWidget *parent = 0); 然而，您将其定义为FindDialog::FindDialog (QDialog *parent)。在两种情况下都使用QDialog或QWidget作为父类型（在这两种情况下，您可能都需要QWidget）。

因此将构造函数定义为： FindDialog::FindDialog (QWidget *parent)

构造函数使用Qt的问题

1 个答案: