src/gui/string_pair_drag.cpp

   1 /*
   2  * string_pair_drag.cpp - class stringPairDrag which provides general support
   3  *                        for drag'n'drop of string-pairs and which is the base
   4  *                        for all drag'n'drop-actions within LMMS
   5  *
   6  * Copyright (c) 2005-2008 Tobias Doerffel <tobydox/at/users.sourceforge.net>
   7  *
   8  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2 of the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public
  21  * License along with this program (see COPYING); if not, write to the
  22  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23  * Boston, MA 02110-1301 USA.
  24  *
  25  */
  26
  27
  28 #include <QtCore/QMimeData>
  29 #include <QtGui/QDragEnterEvent>
  30 #include <QtGui/QDropEvent>
  31
  32
  33 #include "string_pair_drag.h"
  34 #include "engine.h"
  35 #include "MainWindow.h"
  36
  37
  38 stringPairDrag::stringPairDrag( const QString & _key, const QString & _value,
  39                                         const QPixmap & _icon, QWidget * _w ) :
  40         QDrag( _w )
  41 {
  42         if( _icon.isNull() && _w )
  43         {
  44                 setPixmap( QPixmap::grabWidget( _w ).scaled(
  45                                                 64, 64,
  46                                                 Qt::KeepAspectRatio,
  47                                                 Qt::SmoothTransformation ) );
  48         }
  49         else
  50         {
  51                 setPixmap( _icon );
  52         }
  53         QString txt = _key + ":" + _value;
  54         QMimeData * m = new QMimeData();
  55         m->setData( mimeType(), txt.toAscii() );
  56         setMimeData( m );
  57         start( Qt::IgnoreAction );
  58 }
  59
  60
  61
  62
  63 stringPairDrag::~stringPairDrag()
  64 {
  65         // during a drag, we might have lost key-press-events, so reset
  66         // modifiers of main-win
  67         if( engine::mainWindow() )
  68         {
  69                 engine::mainWindow()->clearKeyModifiers();
  70         }
  71 }
  72
  73
  74
  75
  76 bool stringPairDrag::processDragEnterEvent( QDragEnterEvent * _dee,
  77                                                 const QString & _allowed_keys )
  78 {
  79         if( !_dee->mimeData()->hasFormat( mimeType() ) )
  80         {
  81                 return( FALSE );
  82         }
  83         QString txt = _dee->mimeData()->data( mimeType() );
  84         if( _allowed_keys.split( ',' ).contains( txt.section( ':', 0, 0 ) ) )
  85         {
  86                 _dee->acceptProposedAction();
  87                 return( TRUE );
  88         }
  89         _dee->ignore();
  90         return( FALSE );
  91 }
  92
  93
  94
  95
  96 QString stringPairDrag::decodeKey( QDropEvent * _de )
  97 {
  98         return( QString( _de->mimeData()->data( mimeType()
  99                                                 ) ).section( ':', 0, 0 ) );
 100 }
 101
 102
 103
 104
 105 QString stringPairDrag::decodeValue( QDropEvent * _de )
 106 {
 107         return( QString( _de->mimeData()->data( mimeType()
 108                                                 ) ).section( ':', 1, -1 ) );
 109 }
 110
 111