error: incomplete type 'QFileDialog' used in nested name specifier

      在Qte下使用QFileDialog时，编译会出现如上问题。也就是说Qte不支持类QFileDialog。我在网上搜了一下解决方法，有网友提供自己编写的QFileDialog类：

filedialog.h文件

/************************************************************
Copyright (C), 2009, SEU
Author: hxfirefox
FileName: filedialog.h
Date: 12/09/2009
Description: 替代Qt中的QFileDialog
***********************************************************/
#ifndef FILEDLG_H
#define FILEDLG_H

#include <qdir.h>
#include <qdialog.h>

class QListBox;
class QLineEdit;
class QComboBox;
class QLabel;
class QPushButton;


class FileDialog : public QDialog
{
    Q_OBJECT
public:
    FileDialog(const char *dirName, const char *filter = 0, QWidget *parent=0, const char *name=0, bool modal=FALSE);
    FileDialog(QWidget *parent=0, const char *name=0, bool modal=FALSE);
   ~FileDialog();

    QString	selectedFile()	const;

    const char *dirPath() const;
    void	setDir(const char *);
    const QDir *dir() const;
    void	setDir(const QDir &);

    void	rereadDir();

    static QString getOpenFileName(const char *dir = 0, const char *filter = 0, QWidget *parent = 0, const char *name = 0);
    static QString getAllOpenFileNames(const char *dir = 0, const char *filter = 0, QWidget *parent = 0, const char *name = 0);
    static QString getSaveFileName(const char *dir = 0, const char *filter = 0, QWidget *parent = 0, const char *name = 0);

signals:
    void	fileHighlighted(const char *);
    void	fileSelected(const char *);
    void	dirEntered(const char *);

private slots:
    void	fileSelected(int);
    void	fileHighlighted(int);
    void	dirSelected(int);
    void	pathSelected(int);

    void	okClicked();
    void	filterClicked();
    void	cancelClicked();

protected:
    void	resizeEvent(QResizeEvent *);

private:
    void	init();
    void	updatePathBox(const char *);

    QDir	d;
    QString	fileName;

    QListBox   *files;
    QListBox   *dirs;
    QLineEdit  *filterEdit;
    QLineEdit  *nameEdit;
    QComboBox  *pathBox;
    QLabel     *filterL;
    QLabel     *nameL;
    QLabel     *dirL;
    QLabel     *fileL;
    QPushButton *okB;
    QPushButton *filterB;
    QPushButton *cancelB;
};

#endif // FILEDLG_H

 

 

filedialog.cpp文件

/************************************************************
Copyright (C), 2009, SEU
Author: hxfirefox
FileName: filedialog.cpp
Date: 12/09/2009
Description: 替代Qt中的QFileDialog
***********************************************************/
#include "filedialog.h"
#include "qlistbox.h"
#include "qlined.h"
#include "qcombo.h"
#include "qlabel.h"
#include "qpushbt.h"
#include "qmsgbox.h"
#include "qapplication.h"
#include "string.h"

/*************************************************
Function: FileDialog()
Description: 构造函数
Calls: init()
       rereadDir()
       resize()
Input: QWidget *parent
       const char *name
       bool modal
Output: 无
Return: 无
*************************************************/
FileDialog::FileDialog( QWidget *parent, const char *name, bool modal ) : QDialog( parent, name, modal )
{
    init();
    filterEdit->setText( "*" );
    d.convertToAbs();
    rereadDir();
    resize(300, 300);
}

/*************************************************
Function: FileDialog()
Description: 可预设路径与文件名的构造函数
Calls: init()
       rereadDir()
       resize()
Input: const char *dirName
       const char *filter
       QWidget *parent
       const char *name, bool modal
       const char *name
       bool modal
Output: 无
Return: 无
*************************************************/
FileDialog::FileDialog( const char *dirName, const char *filter, QWidget *parent, const char *name, bool modal ) : QDialog( parent, name, modal )
{
    init();
    if(filter)
    {
    	d.setNameFilter(filter);
    }
    filterEdit->setText(d.nameFilter());
    if(dirName)
    {
    	d.setPath(dirName);
    }
    d.convertToAbs();
    rereadDir();
    resize( 300, 300 );
}

/*************************************************
Function: init()
Description: 初始化文件对话框
Calls: connect()
       resize()
       setAutoResize()
       setMatchAllDirs()
Input: 无
Output: 无
Return: 无
*************************************************/
void FileDialog::init()
{
    filterEdit = new QLineEdit(this, "filterEdit");
    pathBox = new QComboBox(this, "pathBox");
    dirs = new QListBox(this, "dirList");
    files = new QListBox(this, "fileList");
    nameEdit = new QLineEdit(this, "nameEdit");
    filterL = new QLabel("Filter:", this, "filterLabel");
    nameL = new QLabel("Name:", this, "filterLabel");
    dirL = new QLabel("Directories:", this, "dirLabel");
    fileL = new QLabel("Files:", this, "fileLabel");
    okB = new QPushButton("OK", this, "okButton");
    filterB = new QPushButton("Filter", this, "filterButton");
    cancelB = new QPushButton("Cancel", this, "cancelButton");

    pathBox->setAutoResize(TRUE );
    filterL->setAutoResize( TRUE );
    nameL->setAutoResize( TRUE );
    dirL->setAutoResize( TRUE );
    fileL->setAutoResize( TRUE );

    okB->resize(50, 25);
    filterB->resize(50, 25);
    cancelB->resize(50, 25);

    connect(files, SIGNAL(selected(int)), SLOT(fileSelected(int)));
    connect(files, SIGNAL(highlighted(int)), SLOT(fileHighlighted(int)));
    connect(dirs, SIGNAL(selected(int)), SLOT(dirSelected(int)));
    connect(pathBox, SIGNAL(activated(int)), SLOT(pathSelected(int)));
    connect(okB,	SIGNAL(clicked()), SLOT(okClicked()));
    connect(nameEdit,	SIGNAL(returnPressed()), SLOT(okClicked()));
    connect(filterEdit, SIGNAL(returnPressed()), SLOT(filterClicked()));
    connect(filterB, SIGNAL(clicked()), SLOT(filterClicked()));
    connect(cancelB,	SIGNAL(clicked()), SLOT(cancelClicked()));
    d.setMatchAllDirs( TRUE );
    d.setSorting(d.sorting()|QDir::DirsFirst);
}


/*************************************************
Function: ~FileDialog()
Description: 析构函数
Calls: 
Input: 无
Output: 无
Return: 无
*************************************************/
FileDialog::~FileDialog()
{
    delete files;
    delete dirs;
    delete filterEdit;
    delete nameEdit;
    delete pathBox;
    delete filterL;
    delete nameL;
    delete dirL;
    delete fileL;
    delete okB;
    delete filterB;
    delete cancelB;
}

/*************************************************
Function: selectedFile()
Description: 返回选中文件名
Calls: text()
Input: 无
Output: 无
Return: 选中文件名
*************************************************/
QString FileDialog::selectedFile() const
{
    QString tmp;
    if (nameEdit->text() && strcmp(nameEdit->text(), "") != 0)
    {
    	tmp = d.absFilePath(nameEdit->text());
    }
    return tmp;
}

/*************************************************
Function: dirPath()
Description: 返回活动目录路径
Calls: path()
Input: 无
Output: 无
Return: 目录路径
*************************************************/
const char *FileDialog::dirPath() const
{
    return d.path();
}

/*************************************************
Function: setDir()
Description: 设置目录路径
Calls: path()
       converToAbs()
       rereadDir()
Input: 无
Output: 无
Return: 无
*************************************************/
void FileDialog::setDir(const char *pathstr)
{
    if (strcmp(d.path(), pathstr) == 0)
    {
    	return;
    }
    d.setPath(pathstr);
    d.convertToAbs();
    rereadDir();
}

/*************************************************
Function: dir()
Description: 返回目录
Calls: 
Input: 无
Output: 无
Return: 目录
*************************************************/
const QDir *FileDialog::dir() const
{
    return &d;
}

void FileDialog::setDir( const QDir &dir )
{
    d = dir;
    d.convertToAbs();
    d.setMatchAllDirs( TRUE );
    d.setSorting(d.sorting() | QDir::DirsFirst);
    rereadDir();
}

/*************************************************
Function: rereadDir()
Description: 刷新目录列表
Calls: setOverrideCursor
       setAutoUpdate()
       clear()
Input: 无
Output: 无
Return: 无
*************************************************/
void FileDialog::rereadDir()
{
    qApp ->setOverrideCursor( waitCursor );
    dirs ->setAutoUpdate( FALSE );
    files->setAutoUpdate( FALSE );
    dirs ->clear();
    files->clear();

    const QFileInfoList	 *filist = d.entryInfoList();
    if (filist)
    {
    	QFileInfoListIterator it(*filist);
    	QFileInfo *fi = it.current();
    	while (fi && fi->isDir())
    	{
    		dirs->insertItem(fi->fileName().data());
    		fi = ++it;
    	}
    	while (fi) 
    	{
    		files->insertItem(fi->fileName().data());
    		fi = ++it;
    	}
    } 
    else
    {
    	qApp->restoreOverrideCursor();
    	QMessageBox::message("Sorry", "Cannot open or read directory.");
    	qApp ->setOverrideCursor(waitCursor);
    }
    dirs ->setAutoUpdate( TRUE );
    files->setAutoUpdate( TRUE );
    dirs ->repaint();
    files->repaint();
    updatePathBox( d.path() );
    qApp->restoreOverrideCursor();
}


/*************************************************
Function: getOpenFileName()
Description: 返回打开文件名
Calls: selectedFile()
Input: 无
Output: 无
Return: 目录
*************************************************/
QString FileDialog::getOpenFileName( const char *dirName, const char *filter, QWidget *parent, const char *name )
{
    FileDialog *dlg = new FileDialog( dirName, filter, parent, name, TRUE );
    CHECK_PTR( dlg );
    dlg->setCaption( "Open" );
    QString result;
    if (dlg->exec() == QDialog::Accepted)
    {
    	result = dlg->selectedFile();
    }
    delete dlg;
    return result;
}

QString FileDialog::getAllOpenFileNames( const char *dirName, const char *filter, QWidget *parent, const char *name )
{
	return getOpenFileName( dirName, filter, parent, name );
}

/*************************************************
Function: getSaveFileName()
Description: 返回保存文件名
Calls: setCaption()
       selectedFile()
Input: const char *dirName
       const char *filter
       QWidget *parent
       const char *name
Output: 无
Return: 保存文件名
*************************************************/
QString FileDialog::getSaveFileName(const char *dirName, const char *filter, QWidget *parent, const char *name)
{
    FileDialog *dlg = new FileDialog( dirName, filter, parent, name, TRUE );
    CHECK_PTR( dlg );
    dlg->setCaption( "Save As" );
    QString result;
    if ( dlg->exec() == QDialog::Accepted)
    {
    	result = dlg->selectedFile();
    }
    delete dlg;
    return result;
}

/*************************************************
Function: fileSelected()
Description: 文件选中时激活
Calls: text()
       accept()
Input: int index
Output: 无
Return: 无
*************************************************/
void FileDialog::fileSelected( int index )
{
    nameEdit->setText( files->text(index) );
    emit fileSelected( d.filePath( nameEdit->text() ) );
    accept();
}

/*************************************************
Function: fileHighlighted()
Description: 文件高亮显示时激活
Calls: setText()
Input: int index
Output: 无
Return: 无
*************************************************/
void FileDialog::fileHighlighted(int index)
{
    nameEdit->setText(files->text(index));
    emit fileHighlighted(d.filePath(files->text(index)));
}

/*************************************************
Function: dirSelected()
Description: 目录选中时激活
Calls: text()
       isReadable()
       path()
       rereadDir()
Input: int index
Output: 无
Return: 无
*************************************************/
void FileDialog::dirSelected( int index )
{
    QDir tmp = d;
    if ( d.cd( dirs->text(index) ) && d.isReadable() )
    {
    	nameEdit->setText("");
    	emit dirEntered(d.path());
    	rereadDir();
    }
    else
    {
    	QMessageBox::message( "Sorry", "Cannot open or read directory." );
    	d = tmp;
    }
}

void FileDialog::pathSelected( int index )
{
    if ( index == 0 )				// current directory shown
    {
    	return;
    }
    QString newPath;
    QDir tmp = d;
    for( int i = pathBox->count() - 1 ; i >= index ; i-- )
    {
    	newPath += pathBox->text( i );
    }
    d.setPath( newPath );
    if (d.isReadable())
    {
    	rereadDir();
    } 
    else 
    {
    	d = tmp;
    }
}

/*************************************************
Function: onClicked()
Description: OK按钮响应
Calls: text()
Input: 无
Output: 无
Return: 无
*************************************************/
void FileDialog::okClicked()
{
    if ( strcmp( nameEdit->text(), "") != 0 )
    {
    	emit fileSelected(d.filePath(nameEdit->text()));
    	accept();
    }
}

/*************************************************
Function: filterClicked()
Description: filter按钮响应
Calls: text()
       rereadDir
Input: 无
Output: 无
Return: 无
*************************************************/
void FileDialog::filterClicked()
{
    if ( strcmp( filterEdit->text(), "" ) == 0 )
	filterEdit->setText( "*" );
    d.setNameFilter( filterEdit->text() );
    rereadDir();
}

/*************************************************
Function: cancelClicked()
Description: cancel按钮响应
Calls: reject()
Input: 无
Output: 无
Return: 无
*************************************************/
void FileDialog::cancelClicked()
{
    reject();
}

void FileDialog::resizeEvent( QResizeEvent * )
{
    int w = width();
    int h = height();
    int	  wTmp;
    QRect rTmp;

    filterL->move( 10, 10 );

    wTmp = filterL->width();
    filterEdit->setGeometry( wTmp + 15, 10, w - wTmp - 15 - 10, 20 );

    rTmp = filterL->geometry();
    wTmp = pathBox->width();
    pathBox->move( (w - wTmp)/2, rTmp.bottom() + 10 );

    rTmp = pathBox->geometry();
    dirL->move( 10, rTmp.bottom() + 5 );

    rTmp = dirL->geometry();
    fileL->move( w / 2 + 5, rTmp.y() );

    rTmp = dirL->geometry();
    dirs->setGeometry(10, rTmp.bottom() + 5,
		      w/2 - 15, h - rTmp.bottom() - 10 - 25 - 10 - 20 - 10 );

    rTmp = dirs->geometry();
    files->setGeometry( rTmp.right() + 10, rTmp.y(),
			rTmp.width(), rTmp.height() );

    rTmp = dirs->geometry();
    nameL->move( 10, rTmp.bottom() + 10 );

    wTmp = nameL->width();
    nameEdit->setGeometry( wTmp + 15, rTmp.bottom() + 10,
			     w - wTmp - 15 - 10, 20 );

    rTmp = nameEdit->geometry();
    okB->move( 10, rTmp.bottom() + 10 );

    rTmp = okB->geometry();
    wTmp = cancelB->width();
    cancelB->move( w - 10 - wTmp, rTmp.y() );

    wTmp = filterB->width();
    filterB->move( (w - wTmp)/2, rTmp.y() );
}

/*************************************************
Function: updatePathBox()
Description: 更新路径
Calls: strcpy()
       insert()
       strtok()
Input: const char *s
Output: 无
Return: 无
*************************************************/
void FileDialog::updatePathBox( const char *s )
{
    QStrList l;
    QString tmp;
    char* tmps = new char[100];
    strcpy(tmps, s);

    l.insert( 0, "/" );
    tmp = strtok(tmps, "/");
    while( TRUE ) 
    {
    	if (tmp.isNull())
    	{
    		break;
    	}
    	l.insert( 0, tmp + "/" );
    	tmp = strtok( 0, "/" );
    }
    pathBox->setUpdatesEnabled( FALSE );
    pathBox->clear();
    pathBox->insertStrList( &l );
    pathBox->setCurrentItem( 0 );
    pathBox->move((width() - pathBox->width()) / 2, pathBox->geometry().y());
    pathBox->setUpdatesEnabled( TRUE );
    pathBox->repaint();
}

把上面两个文件filedialog.h和filedialog.cpp放到qt2的include目录下。然后在你的程序上加上

#include <filedialog.h>即可。