Fix segfault when moving channels

This commit addresses a lot of issues, namely:

1. When the "Move left/right" action was selected on a mixer channel
menu sometimes it would segfault due to the fxline object being
deleted before it returned to a method inside itself

2. The Fader was declaring a new variable for the model whereas it
should used the inherited model from FloatModelView < AutomatableModelView

3. Some methods were doing more things than they should be and
performing unnecessary actions. A little cleanup/refactor was made

Please notice that a bug of the same class as the one referred at point 1
still exists: clicking on "Remove channel". This commit does not
addresses this issue.

Fixes #1584

include/Fader.h

@@ -100,14 +100,12 @@ private:
 
 	int knobPosY() const
 	{
-		float fRange = m_model->maxValue() - m_model->minValue();
-		float realVal = m_model->value() - m_model->minValue();
+		float fRange = model()->maxValue() - model()->minValue();
+		float realVal = model()->value() - model()->minValue();
 
 		return height() - ( ( height() - m_knob->height() ) * ( realVal / fRange ) );
 	}
 
-	FloatModel * m_model;
-
 	void setPeak( float fPeak, float &targetPeak, float &persistentPeak, QTime &lastPeakTime );
 	int calculateDisplayPeak( float fPeak );
 

include/FxMixerView.h

@@ -53,6 +53,8 @@ public:
 	public:
 		FxChannelView(QWidget * _parent, FxMixerView * _mv, int _chIndex );
 
+		void setChannelIndex( int index );
+
 		FxLine * m_fxLine;
 		PixmapButton * m_muteBtn;
 		PixmapButton * m_soloBtn;
@@ -97,6 +99,7 @@ public:
 
 	// move the channel to the left or right
 	void moveChannelLeft(int index);
+	void moveChannelLeft(int index, int focusIndex);
 	void moveChannelRight(int index);
 
 	// make sure the display syncs up with the fx mixer.

src/core/FxMixer.cpp

@@ -327,6 +327,19 @@ void FxMixer::deleteChannel( int index )
 	for( int i = index; i < m_fxChannels.size(); ++i )
 	{
 		validateChannelName( i, i + 1 );
+
+		// set correct channel index
+		m_fxChannels[i]->m_channelIndex = i;
+
+		// now check all routes and update names of the send models
+		foreach( FxRoute * r, m_fxChannels[i]->m_sends )
+		{
+			r->updateName();
+		}
+		foreach( FxRoute * r, m_fxChannels[i]->m_receives )
+		{
+			r->updateName();
+		}
 	}
 }
 
@@ -364,18 +377,9 @@ void FxMixer::moveChannelLeft( int index )
 				{
 					inst->effectChannelModel()->setValue(a);
 				}
-
 			}
 		}
 	}
-
-	// actually do the swap
-	FxChannel * tmpChannel = m_fxChannels[a];
-	m_fxChannels[a] = m_fxChannels[b];
-	m_fxChannels[b] = tmpChannel;
-
-	validateChannelName( a, b );
-	validateChannelName( b, a );
 }
 
 
@@ -758,22 +762,9 @@ void FxMixer::loadSettings( const QDomElement & _this )
 
 void FxMixer::validateChannelName( int index, int oldIndex )
 {
-	FxChannel * fxc = m_fxChannels[ index ];
-	if( fxc->m_name == tr( "FX %1" ).arg( oldIndex ) )
+	if( m_fxChannels[index]->m_name == tr( "FX %1" ).arg( oldIndex ) )
 	{
-		fxc->m_name = tr( "FX %1" ).arg( index );
-	}
-	// set correct channel index
-	fxc->m_channelIndex = index;
-
-	// now check all routes and update names of the send models
-	foreach( FxRoute * r, fxc->m_sends )
-	{
-		r->updateName();
-	}
-	foreach( FxRoute * r, fxc->m_receives )
-	{
-		r->updateName();
+		m_fxChannels[index]->m_name = tr( "FX %1" ).arg( index );
 	}
 }
 

src/gui/FxMixerView.cpp

@@ -267,19 +267,20 @@ void FxMixerView::loadSettings( const QDomElement & _this )
 
 
 FxMixerView::FxChannelView::FxChannelView(QWidget * _parent, FxMixerView * _mv,
-										  int _chIndex )
+										  int channelIndex )
 {
-	m_fxLine = new FxLine(_parent, _mv, _chIndex);
+	m_fxLine = new FxLine(_parent, _mv, channelIndex);
 
-	FxMixer * m = Engine::fxMixer();
-	m_fader = new Fader( &m->effectChannel(_chIndex)->m_volumeModel,
-					tr( "FX Fader %1" ).arg( _chIndex ), m_fxLine );
+	FxChannel *fxChannel = Engine::fxMixer()->effectChannel(channelIndex);
+
+	m_fader = new Fader( &fxChannel->m_volumeModel,
+					tr( "FX Fader %1" ).arg( channelIndex ), m_fxLine );
 	m_fader->move( 16-m_fader->width()/2,
 					m_fxLine->height()-
 					m_fader->height()-5 );
 
 	m_muteBtn = new PixmapButton( m_fxLine, tr( "Mute" ) );
-	m_muteBtn->setModel( &m->effectChannel(_chIndex)->m_muteModel );
+	m_muteBtn->setModel( &fxChannel->m_muteModel );
 	m_muteBtn->setActiveGraphic(
 				embed::getIconPixmap( "led_off" ) );
 	m_muteBtn->setInactiveGraphic(
@@ -289,23 +290,34 @@ FxMixerView::FxChannelView::FxChannelView(QWidget * _parent, FxMixerView * _mv,
 	ToolTip::add( m_muteBtn, tr( "Mute this FX channel" ) );
 
 	m_soloBtn = new PixmapButton( m_fxLine, tr( "Solo" ) );
-	m_soloBtn->setModel( &m->effectChannel(_chIndex)->m_soloModel );
+	m_soloBtn->setModel( &fxChannel->m_soloModel );
 	m_soloBtn->setActiveGraphic(
 				embed::getIconPixmap( "led_red" ) );
 	m_soloBtn->setInactiveGraphic(
 				embed::getIconPixmap( "led_off" ) );
 	m_soloBtn->setCheckable( true );
 	m_soloBtn->move( 9,  m_fader->y()-21);
-	connect(&m->effectChannel(_chIndex)->m_soloModel, SIGNAL( dataChanged() ),
+	connect(&fxChannel->m_soloModel, SIGNAL( dataChanged() ),
 			_mv, SLOT ( toggledSolo() ) );
 	ToolTip::add( m_soloBtn, tr( "Solo FX channel" ) );
 	
 	// Create EffectRack for the channel
-	m_rackView = new EffectRackView( &m->effectChannel(_chIndex)->m_fxChain, _mv->m_racksWidget );
+	m_rackView = new EffectRackView( &fxChannel->m_fxChain, _mv->m_racksWidget );
 	m_rackView->setFixedSize( 245, FxLine::FxLineHeight );
 }
 
 
+void FxMixerView::FxChannelView::setChannelIndex( int index )
+{
+	FxChannel* fxChannel = Engine::fxMixer()->effectChannel( index );
+
+	m_fader->setModel( &fxChannel->m_volumeModel );
+	m_muteBtn->setModel( &fxChannel->m_muteModel );
+	m_soloBtn->setModel( &fxChannel->m_soloModel );
+	m_rackView->setModel( &fxChannel->m_fxChain );
+}
+
+
 void FxMixerView::toggledSolo()
 {
 	Engine::fxMixer()->toggledSolo();
@@ -432,53 +444,39 @@ void FxMixerView::deleteUnusedChannels()
 
 
 
-void FxMixerView::moveChannelLeft(int index)
+void FxMixerView::moveChannelLeft(int index, int focusIndex)
 {
 	// can't move master or first channel left or last channel right
 	if( index <= 1 || index >= m_fxChannelViews.size() ) return;
 
-	int selIndex = m_currentFxLine->channelIndex();
+	FxMixer *m = Engine::fxMixer();
 
-	FxMixer * mix = Engine::fxMixer();
-	mix->moveChannelLeft(index);
+	// Move instruments channels
+	m->moveChannelLeft( index );
 
-	// refresh the two mixer views
-	for( int i = index-1; i <= index; ++i )
-	{
-		// delete the mixer view
-		int replaceIndex = chLayout->indexOf(m_fxChannelViews[i]->m_fxLine);
+	// Update widgets models
+	m_fxChannelViews[index]->setChannelIndex( index - 1 );
+	m_fxChannelViews[index - 1]->setChannelIndex( index );
 
-		chLayout->removeWidget(m_fxChannelViews[i]->m_fxLine);
-		m_racksLayout->removeWidget( m_fxChannelViews[i]->m_rackView );
-		delete m_fxChannelViews[i]->m_fader;
-		delete m_fxChannelViews[i]->m_muteBtn;
-		delete m_fxChannelViews[i]->m_soloBtn;
-		delete m_fxChannelViews[i]->m_fxLine;
-		delete m_fxChannelViews[i];
+	// Swap positions in array
+	qSwap(m->m_fxChannels[index], m->m_fxChannels[index - 1]);
 
-		// add it again
-		m_fxChannelViews[i] = new FxChannelView( m_channelAreaWidget, this, i );
-		chLayout->insertWidget( replaceIndex, m_fxChannelViews[i]->m_fxLine );
-		m_racksLayout->insertWidget( replaceIndex, m_fxChannelViews[i]->m_rackView );
-	}
+	// Focus on new position
+	setCurrentFxLine( focusIndex );
+}
 
-	// keep selected channel
-	if( selIndex == index )
-	{
-		selIndex = index-1;
-	}
-	else if( selIndex == index - 1 )
-	{
-		selIndex = index;
-	}
-	setCurrentFxLine(selIndex);
+
+
+void FxMixerView::moveChannelLeft(int index)
+{
+	moveChannelLeft( index, index - 1 );
 }
 
 
 
 void FxMixerView::moveChannelRight(int index)
 {
-	moveChannelLeft(index+1);
+	moveChannelLeft( index + 1, index + 1 );
 }
 
 

src/gui/widgets/Fader.cpp

@@ -67,7 +67,6 @@ QPixmap * Fader::s_knob = NULL;
 Fader::Fader( FloatModel * _model, const QString & _name, QWidget * _parent ) :
 	QWidget( _parent ),
 	FloatModelView( _model, this ),
-	m_model( _model ),
 	m_fPeakValue_L( 0.0 ),
 	m_fPeakValue_R( 0.0 ),
 	m_persistentPeak_L( 0.0 ),
@@ -114,7 +113,6 @@ Fader::Fader( FloatModel * _model, const QString & _name, QWidget * _parent ) :
 Fader::Fader( FloatModel * model, const QString & name, QWidget * parent, QPixmap * back, QPixmap * leds, QPixmap * knob ) :
 	QWidget( parent ),
 	FloatModelView( model, this ),
-	m_model( model ),
 	m_fPeakValue_L( 0.0 ),
 	m_fPeakValue_R( 0.0 ),
 	m_persistentPeak_L( 0.0 ),
@@ -170,7 +168,7 @@ void Fader::mouseMoveEvent( QMouseEvent *mouseEvent )
 	{
 		int dy = m_moveStartPoint - mouseEvent->globalY();
 
-		float delta = dy * ( m_model->maxValue() - m_model->minValue() ) / (float) ( height() - ( *m_knob ).height() );
+		float delta = dy * ( model()->maxValue() - model()->minValue() ) / (float) ( height() - ( *m_knob ).height() );
 
 		model()->setValue( m_startValue + delta );
 
@@ -256,11 +254,11 @@ void Fader::wheelEvent ( QWheelEvent *ev )
 
 	if ( ev->delta() > 0 )
 	{
-		m_model->incValue( 1 );
+		model()->incValue( 1 );
 	}
 	else
 	{
-		m_model->incValue( -1 );
+		model()->incValue( -1 );
 	}
 	updateTextFloat();
 	s_textFloat->setVisibilityTimeOut( 1000 );
@@ -326,7 +324,7 @@ void Fader::updateTextFloat()
 	}
 	else
 	{
-		s_textFloat->setText( m_description + " " + QString("%1 ").arg( m_displayConversion ? m_model->value() * 100 : m_model->value() ) + " " + m_unit );
+		s_textFloat->setText( m_description + " " + QString("%1 ").arg( m_displayConversion ? model()->value() * 100 : model()->value() ) + " " + m_unit );
 	}
 	s_textFloat->moveGlobal( this, QPoint( width() - ( *m_knob ).width() - 5, knobPosY() - 46 ) );
 }