Viadeo Twitter Google Bookmarks ! Facebook Digg del.icio.us MySpace Yahoo MyWeb Blinklist Netvouz Reddit Simpy StumbleUpon Bookmarks Windows Live Favorites 
Logo Documentation Qt ·  Page d'accueil  ·  Toutes les classes  ·  Classes principales  ·  Annotées  ·  Classes groupées  ·  Fonctions  · 

A Directory Browser

This example program demonstrates how to use a listview and listview items to build a multi-column hierarchical, memory- and CPU-efficient directory browser. It also demonstrates how to use Drag&Drop in a listview.


Header file:

/****************************************************************************
** $Id: $
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of an example program for Qt.  This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/

#ifndef DIRVIEW_H
#define DIRVIEW_H

#include <qlistview.h>
#include <qstring.h>
#include <qfile.h>
#include <qfileinfo.h>
#include <qtimer.h>

class QWidget;
class QDragEnterEvent;
class QDragMoveEvent;
class QDragLeaveEvent;
class QDropEvent;

class FileItem : public QListViewItem
{
public:
    FileItem( QListViewItem *parent, const QString &s1, const QString &s2 )
        : QListViewItem( parent, s1, s2 ), pix( 0 ) {}

    const QPixmap *pixmap( int i ) const;
#if !defined(Q_NO_USING_KEYWORD)
    using QListViewItem::setPixmap;
#endif
    void setPixmap( QPixmap *p );

private:
    QPixmap *pix;

};

class Directory : public QListViewItem
{
public:
    Directory( QListView * parent, const QString& filename );
    Directory( Directory * parent, const QString& filename, const QString &col2 )
        : QListViewItem( parent, filename, col2 ), pix( 0 ) {}
    Directory( Directory * parent, const QString& filename );

    QString text( int column ) const;

    QString fullName();

    void setOpen( bool );
    void setup();

    const QPixmap *pixmap( int i ) const;
#if !defined(Q_NO_USING_KEYWORD)
    using QListViewItem::setPixmap;
#endif
    void setPixmap( QPixmap *p );

private:
    QFile f;
    Directory * p;
    bool readable;
    bool showDirsOnly;
    QPixmap *pix;

};

class DirectoryView : public QListView
{
    Q_OBJECT

public:
    DirectoryView( QWidget *parent = 0, const char *name = 0, bool sdo = FALSE );
    bool showDirsOnly() { return dirsOnly; }

public slots:
    void setDir( const QString & );

signals:
    void folderSelected( const QString & );

protected slots:
    void slotFolderSelected( QListViewItem * );
    void openFolder();

protected:
    void contentsDragEnterEvent( QDragEnterEvent *e );
    void contentsDragMoveEvent( QDragMoveEvent *e );
    void contentsDragLeaveEvent( QDragLeaveEvent *e );
    void contentsDropEvent( QDropEvent *e );
    void contentsMouseMoveEvent( QMouseEvent *e );
    void contentsMousePressEvent( QMouseEvent *e );
    void contentsMouseReleaseEvent( QMouseEvent *e );

private:
    QString fullPath(QListViewItem* item);
    bool dirsOnly;
    QListViewItem *oldCurrent;
    QListViewItem *dropItem;
    QTimer* autoopen_timer;
    QPoint presspos;
    bool mousePressed;

};

#endif


And here is the main implementation file. Note the way the program scans subdirectories only when it has to. This allows the program to handle very large file systems efficiently. The same technique can be used in any other trees.

/****************************************************************************
** $Id: $
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of an example program for Qt.  This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/

#include "dirview.h"

#include <qdir.h>
#include <qfile.h>
#include <qfileinfo.h>
#include <qpixmap.h>
#include <qevent.h>
#include <qpoint.h>
#include <qmessagebox.h>
#include <qdragobject.h>
#include <qmime.h>
#include <qstrlist.h>
#include <qstringlist.h>
#include <qapplication.h>
#include <qheader.h>

static const char* folder_closed_xpm[]={
    "16 16 9 1",
    "g c #808080",
    "b c #c0c000",
    "e c #c0c0c0",
    "# c #000000",
    "c c #ffff00",
    ". c None",
    "a c #585858",
    "f c #a0a0a4",
    "d c #ffffff",
    "..###...........",
    ".#abc##.........",
    ".#daabc#####....",
    ".#ddeaabbccc#...",
    ".#dedeeabbbba...",
    ".#edeeeeaaaab#..",
    ".#deeeeeeefe#ba.",
    ".#eeeeeeefef#ba.",
    ".#eeeeeefeff#ba.",
    ".#eeeeefefff#ba.",
    ".##geefeffff#ba.",
    "...##gefffff#ba.",
    ".....##fffff#ba.",
    ".......##fff#b##",
    ".........##f#b##",
    "...........####."};

static const char* folder_open_xpm[]={
    "16 16 11 1",
    "# c #000000",
    "g c #c0c0c0",
    "e c #303030",
    "a c #ffa858",
    "b c #808080",
    "d c #a0a0a4",
    "f c #585858",
    "c c #ffdca8",
    "h c #dcdcdc",
    "i c #ffffff",
    ". c None",
    "....###.........",
    "....#ab##.......",
    "....#acab####...",
    "###.#acccccca#..",
    "#ddefaaaccccca#.",
    "#bdddbaaaacccab#",
    ".eddddbbaaaacab#",
    ".#bddggdbbaaaab#",
    "..edgdggggbbaab#",
    "..#bgggghghdaab#",
    "...ebhggghicfab#",
    "....#edhhiiidab#",
    "......#egiiicfb#",
    "........#egiibb#",
    "..........#egib#",
    "............#ee#"};

static const char * folder_locked[]={
    "16 16 10 1",
    "h c #808080",
    "b c #ffa858",
    "f c #c0c0c0",
    "e c #c05800",
    "# c #000000",
    "c c #ffdca8",
    ". c None",
    "a c #585858",
    "g c #a0a0a4",
    "d c #ffffff",
    "..#a#...........",
    ".#abc####.......",
    ".#daa#eee#......",
    ".#ddf#e##b#.....",
    ".#dfd#e#bcb##...",
    ".#fdccc#daaab#..",
    ".#dfbbbccgfg#ba.",
    ".#ffb#ebbfgg#ba.",
    ".#ffbbe#bggg#ba.",
    ".#fffbbebggg#ba.",
    ".##hf#ebbggg#ba.",
    "...###e#gggg#ba.",
    ".....#e#gggg#ba.",
    "......###ggg#b##",
    ".........##g#b##",
    "...........####."};

static const char * pix_file []={
    "16 16 7 1",
    "# c #000000",
    "b c #ffffff",
    "e c #000000",
    "d c #404000",
    "c c #c0c000",
    "a c #ffffc0",
    ". c None",
    "................",
    ".........#......",
    "......#.#a##....",
    ".....#b#bbba##..",
    "....#b#bbbabbb#.",
    "...#b#bba##bb#..",
    "..#b#abb#bb##...",
    ".#a#aab#bbbab##.",
    "#a#aaa#bcbbbbbb#",
    "#ccdc#bcbbcbbb#.",
    ".##c#bcbbcabb#..",
    "...#acbacbbbe...",
    "..#aaaacaba#....",
    "...##aaaaa#.....",
    ".....##aa#......",
    ".......##......."};

QPixmap *folderLocked = 0;
QPixmap *folderClosed = 0;
QPixmap *folderOpen = 0;
QPixmap *fileNormal = 0;

/*****************************************************************************
 *
 * Class Directory
 *
 *****************************************************************************/

Directory::Directory( Directory * parent, const QString& filename )
    : QListViewItem( parent ), f(filename),
      showDirsOnly( parent->showDirsOnly ),
      pix( 0 )
{
    p = parent;
    readable = QDir( fullName() ).isReadable();

    if ( !readable )
        setPixmap( folderLocked );
    else
        setPixmap( folderClosed );
}


Directory::Directory( QListView * parent, const QString& filename )
    : QListViewItem( parent ), f(filename),
      showDirsOnly( ( (DirectoryView*)parent )->showDirsOnly() ),
      pix( 0 )
{
    p = 0;
    readable = QDir( fullName() ).isReadable();
}


void Directory::setPixmap( QPixmap *px )
{
    pix = px;
    setup();
    widthChanged( 0 );
    invalidateHeight();
    repaint();
}


const QPixmap *Directory::pixmap( int i ) const
{
    if ( i )
        return 0;
    return pix;
}

void Directory::setOpen( bool o )
{
    if ( o )
        setPixmap( folderOpen );
    else
        setPixmap( folderClosed );

    if ( o && !childCount() ) {
        QString s( fullName() );
        QDir thisDir( s );
        if ( !thisDir.isReadable() ) {
            readable = FALSE;
            setExpandable( FALSE );
            return;
        }

        listView()->setUpdatesEnabled( FALSE );
        const QFileInfoList * files = thisDir.entryInfoList();
        if ( files ) {
            QFileInfoListIterator it( *files );
            QFileInfo * fi;
            while( (fi=it.current()) != 0 ) {
                ++it;
                if ( fi->fileName() == "." || fi->fileName() == ".." )
                    ; // nothing
                else if ( fi->isSymLink() && !showDirsOnly ) {
                    FileItem *item = new FileItem( this, fi->fileName(),
                                                     "Symbolic Link" );
                    item->setPixmap( fileNormal );
                }
                else if ( fi->isDir() )
                    (void)new Directory( this, fi->fileName() );
                else if ( !showDirsOnly ) {
                    FileItem *item
                        = new FileItem( this, fi->fileName(),
                                             fi->isFile()?"File":"Special" );
                    item->setPixmap( fileNormal );
                }
            }
        }
        listView()->setUpdatesEnabled( TRUE );
    }
    QListViewItem::setOpen( o );
}


void Directory::setup()
{
    setExpandable( TRUE );
    QListViewItem::setup();
}


QString Directory::fullName()
{
    QString s;
    if ( p ) {
        s = p->fullName();
        s.append( f.name() );
        s.append( "/" );
    } else {
        s = f.name();
    }
    return s;
}


QString Directory::text( int column ) const
{
    if ( column == 0 )
        return f.name();
    else if ( readable )
        return "Directory";
    else
        return "Unreadable Directory";
}

/*****************************************************************************
 *
 * Class DirectoryView
 *
 *****************************************************************************/

DirectoryView::DirectoryView( QWidget *parent, const char *name, bool sdo )
    : QListView( parent, name ), dirsOnly( sdo ), oldCurrent( 0 ),
      dropItem( 0 ), mousePressed( FALSE )
{
    autoopen_timer = new QTimer( this );
    if ( !folderLocked ) {
        folderLocked = new QPixmap( folder_locked );
        folderClosed = new QPixmap( folder_closed_xpm );
        folderOpen = new QPixmap( folder_open_xpm );
        fileNormal = new QPixmap( pix_file );
    }

    connect( this, SIGNAL( doubleClicked( QListViewItem * ) ),
             this, SLOT( slotFolderSelected( QListViewItem * ) ) );
    connect( this, SIGNAL( returnPressed( QListViewItem * ) ),
             this, SLOT( slotFolderSelected( QListViewItem * ) ) );

    setAcceptDrops( TRUE );
    viewport()->setAcceptDrops( TRUE );

    connect( autoopen_timer, SIGNAL( timeout() ),
             this, SLOT( openFolder() ) );
}

void DirectoryView::slotFolderSelected( QListViewItem *i )
{
    if ( !i || !showDirsOnly() )
        return;

    Directory *dir = (Directory*)i;
    emit folderSelected( dir->fullName() );
}

void DirectoryView::openFolder()
{
    autoopen_timer->stop();
    if ( dropItem && !dropItem->isOpen() ) {
        dropItem->setOpen( TRUE );
        dropItem->repaint();
    }
}

static const int autoopenTime = 750;


void DirectoryView::contentsDragEnterEvent( QDragEnterEvent *e )
{
    if ( !QUriDrag::canDecode(e) ) {
        e->ignore();
        return;
    }

    oldCurrent = currentItem();

    QListViewItem *i = itemAt( contentsToViewport(e->pos()) );
    if ( i ) {
        dropItem = i;
        autoopen_timer->start( autoopenTime );
    }
}


void DirectoryView::contentsDragMoveEvent( QDragMoveEvent *e )
{
    if ( !QUriDrag::canDecode(e) ) {
        e->ignore();
        return;
    }

    QPoint vp = contentsToViewport( ( (QDragMoveEvent*)e )->pos() );
    QListViewItem *i = itemAt( vp );
    if ( i ) {
        setSelected( i, TRUE );
        e->accept();
        if ( i != dropItem ) {
            autoopen_timer->stop();
            dropItem = i;
            autoopen_timer->start( autoopenTime );
        }
        switch ( e->action() ) {
        case QDropEvent::Copy:
            break;
        case QDropEvent::Move:
            e->acceptAction();
            break;
        case QDropEvent::Link:
            e->acceptAction();
            break;
        default:
            ;
        }
    } else {
        e->ignore();
        autoopen_timer->stop();
        dropItem = 0;
    }
}

void DirectoryView::contentsDragLeaveEvent( QDragLeaveEvent * )
{
    autoopen_timer->stop();
    dropItem = 0;

    setCurrentItem( oldCurrent );
    setSelected( oldCurrent, TRUE );
}

void DirectoryView::contentsDropEvent( QDropEvent *e )
{
    autoopen_timer->stop();

    if ( !QUriDrag::canDecode(e) ) {
        e->ignore();
        return;
    }

    QListViewItem *item = itemAt( contentsToViewport(e->pos()) );
    if ( item ) {

        QStrList lst;

        QUriDrag::decode( e, lst );

        QString str;

        switch ( e->action() ) {
            case QDropEvent::Copy:
            str = "Copy";
            break;
            case QDropEvent::Move:
            str = "Move";
            e->acceptAction();
            break;
            case QDropEvent::Link:
            str = "Link";
            e->acceptAction();
            break;
            default:
            str = "Unknown";
        }

        str += "\n\n";

        e->accept();

        for ( uint i = 0; i < lst.count(); ++i ) {
            QString filename = QDir::convertSeparators(QUriDrag::uriToLocalFile(lst.at(i)));
            str += filename + "\n";
        }
        str += QString( "\nTo\n\n   %1" )
            .arg( QDir::convertSeparators(fullPath(item)) );

        QMessageBox::information( this, "Drop target", str, "Not implemented" );
    } else
        e->ignore();

}


QString DirectoryView::fullPath(QListViewItem* item)
{
    QString fullpath = item->text(0);
    while ( (item=item->parent()) ) {
        if ( item->parent() )
            fullpath = item->text(0) + "/" + fullpath;
        else
            fullpath = item->text(0) + fullpath;
    }
#ifdef Q_WS_WIN
        if (fullpath.length() > 2 && fullpath[1] != ':') {
                QDir dir(fullpath);
                fullpath = dir.currentDirPath().left(2) + fullpath;
        }
#endif

    return fullpath;
}

void DirectoryView::contentsMousePressEvent( QMouseEvent* e )
{
    QListView::contentsMousePressEvent(e);
    QPoint p( contentsToViewport( e->pos() ) );
    QListViewItem *i = itemAt( p );
    if ( i ) {
        // if the user clicked into the root decoration of the item, don't try to start a drag!
        if ( p.x() > header()->cellPos( header()->mapToActual( 0 ) ) +
             treeStepSize() * ( i->depth() + ( rootIsDecorated() ? 1 : 0) ) + itemMargin() ||
             p.x() < header()->cellPos( header()->mapToActual( 0 ) ) ) {
            presspos = e->pos();
            mousePressed = TRUE;
        }
    }
}

void DirectoryView::contentsMouseMoveEvent( QMouseEvent* e )
{
    if ( mousePressed && ( presspos - e->pos() ).manhattanLength() > QApplication::startDragDistance() ) {
        mousePressed = FALSE;
        QListViewItem *item = itemAt( contentsToViewport(presspos) );
        if ( item ) {
            QString source = fullPath(item);
            if ( QFile::exists(source) ) {
                QUriDrag* ud = new QUriDrag(viewport());
                ud->setFileNames( source );
                if ( ud->drag() )
                    QMessageBox::information( this, "Drag source",
                    QString("Delete ") + QDir::convertSeparators(source), "Not implemented" );
            }
        }
    }
}

void DirectoryView::contentsMouseReleaseEvent( QMouseEvent * )
{
    mousePressed = FALSE;
}

void DirectoryView::setDir( const QString &s )
{
    QListViewItemIterator it( this );
    ++it;
    for ( ; it.current(); ++it ) {
        it.current()->setOpen( FALSE );
    }

    QStringList lst( QStringList::split( "/", s ) );
    QListViewItem *item = firstChild();
    QStringList::Iterator it2 = lst.begin();
    for ( ; it2 != lst.end(); ++it2 ) {
        while ( item ) {
            if ( item->text( 0 ) == *it2 ) {
                item->setOpen( TRUE );
                break;
            }
            item = item->itemBelow();
        }
    }

    if ( item )
        setCurrentItem( item );
}

void FileItem::setPixmap( QPixmap *p )
{
    pix = p;
    setup();
    widthChanged( 0 );
    invalidateHeight();
    repaint();
}


const QPixmap *FileItem::pixmap( int i ) const
{
    if ( i )
        return 0;
    return pix;
}


Main:

/****************************************************************************
** $Id: $
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of an example program for Qt.  This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/

#include <qapplication.h>
#include <qfileinfo.h>
#include <qdir.h>
#include "dirview.h"

int main( int argc, char ** argv )
{
    QApplication a( argc, argv );

    DirectoryView mw;

    mw.addColumn( "Name" );
    mw.addColumn( "Type" );
    mw.setTreeStepSize( 20 );

    const QFileInfoList* roots = QDir::drives();
    QPtrListIterator<QFileInfo> i(*roots);
    QFileInfo* fi;
    while ( (fi = *i) ) {
        ++i;
        Directory * root = new Directory( &mw, fi->filePath() );
        if ( roots->count() <= 1 )
            root->setOpen( TRUE ); // be interesting
    }

    mw.resize( 400, 400 );
    mw.setCaption( "Qt Example - Directory Browser" );
    mw.setAllColumnsShowFocus( TRUE );
    a.setMainWidget( &mw );
    mw.show();

    return a.exec();
}

See also Examples.

Publicité

Best Of

Actualités les plus lues

Semaine
Mois
Année
  1. « Quelque chose ne va vraiment pas avec les développeurs "modernes" », un développeur à "l'ancienne" critique la multiplication des bibliothèques 94
  2. Apercevoir la troisième dimension ou l'utilisation multithreadée d'OpenGL dans Qt, un article des Qt Quarterly traduit par Guillaume Belz 0
  3. Les développeurs ignorent-ils trop les failles découvertes dans leur code ? Prenez-vous en compte les remarques des autres ? 17
  4. Pourquoi les programmeurs sont-ils moins payés que les gestionnaires de programmes ? Manquent-ils de pouvoir de négociation ? 42
  5. Quelles nouveautés de C++11 Visual C++ doit-il rapidement intégrer ? Donnez-nous votre avis 10
  6. Adieu qmake, bienvenue qbs : Qt Building Suite, un outil déclaratif et extensible pour la compilation de projets Qt 17
  7. 2017 : un quinquennat pour une nouvelle version du C++ ? Possible, selon Herb Sutter 6
Page suivante

Le Qt Quarterly au hasard

Logo

Requête de données génériques avec QtXmlPatterns et XQuery

Qt Quarterly est la revue trimestrielle proposée par Nokia et à destination des développeurs Qt. Ces articles d'une grande qualité technique sont rédigés par des experts Qt. Lire l'article.

Communauté

Ressources

Liens utiles

Contact

  • Vous souhaitez rejoindre la rédaction ou proposer un tutoriel, une traduction, une question... ? Postez dans le forum Contribuez ou contactez-nous par MP ou par email (voir en bas de page).

Qt dans le magazine

Cette page est une traduction d'une page de la documentation de Qt, écrite par Nokia Corporation and/or its subsidiary(-ies). Les éventuels problèmes résultant d'une mauvaise traduction ne sont pas imputables à Nokia. Qt 3.2
Copyright © 2012 Developpez LLC. Tous droits réservés Developpez LLC. Aucune reproduction, même partielle, ne peut être faite de ce site et de l'ensemble de son contenu : textes, documents et images sans l'autorisation expresse de Developpez LLC. Sinon, vous encourez selon la loi jusqu'à 3 ans de prison et jusqu'à 300 000 E de dommages et intérêts. Cette page est déposée à la SACD.
Vous avez déniché une erreur ? Un bug ? Une redirection cassée ? Ou tout autre problème, quel qu'il soit ? Ou bien vous désirez participer à ce projet de traduction ? N'hésitez pas à nous contacter ou par MP !
 
 
 
 
Partenaires

Hébergement Web