Simplify TrackLabelButton

Remove the dependency to `Instrument` and `InstrumentTrack` from `TrackLabelButton`. The icon of an `InstrumentTrackView` is now determined in the class `InstrumentTrackView` itself using the new method `determinePixmap`. This enables the removal of the overridden `paintEvent` method from `TrackLabelButton`.

include/InstrumentTrackView.h

@@ -93,6 +93,8 @@ private slots:
 
 	void handleConfigChange(QString cls, QString attr, QString value);
 
+private:
+	QPixmap determinePixmap(InstrumentTrack * instrumentTrack);
 
 private:
 	InstrumentTrackWindow * m_window;

include/TrackLabelButton.h

@@ -55,7 +55,6 @@ protected:
 	void mousePressEvent( QMouseEvent * _me ) override;
 	void mouseDoubleClickEvent( QMouseEvent * _me ) override;
 	void mouseReleaseEvent( QMouseEvent * _me ) override;
-	void paintEvent( QPaintEvent * _pe ) override;
 	void resizeEvent( QResizeEvent * _re ) override;
 
 

src/gui/tracks/InstrumentTrackView.cpp

@@ -40,6 +40,7 @@
 #include "Mixer.h"
 #include "MixerView.h"
 #include "GuiApplication.h"
+#include "Instrument.h"
 #include "InstrumentTrack.h"
 #include "InstrumentTrackWindow.h"
 #include "MainWindow.h"
@@ -62,7 +63,7 @@ InstrumentTrackView::InstrumentTrackView( InstrumentTrack * _it, TrackContainerV
 
 	m_tlb = new TrackLabelButton( this, getTrackSettingsWidget() );
 	m_tlb->setCheckable( true );
-	m_tlb->setIcon( embed::getIconPixmap( "instrument_track" ) );
+	m_tlb->setIcon(determinePixmap(_it));
 	m_tlb->show();
 
 	connect( m_tlb, SIGNAL(toggled(bool)),
@@ -393,4 +394,27 @@ QMenu * InstrumentTrackView::createMixerMenu(QString title, QString newMixerLabe
 }
 
 
+QPixmap InstrumentTrackView::determinePixmap(InstrumentTrack * instrumentTrack)
+{
+	if (instrumentTrack)
+	{
+		Instrument * instrument = instrumentTrack->instrument();
+
+		if (instrument && instrument->descriptor())
+		{
+			const PixmapLoader * pl = instrument->key().isValid() ?
+				instrument->key().logo() :
+				instrument->descriptor()->logo;
+
+			if(pl)
+			{
+				return pl->pixmap();
+			}
+		}
+	}
+
+	return embed::getIconPixmap("instrument_track");
+}
+
+
 } // namespace lmms::gui

src/gui/tracks/TrackLabelButton.cpp

@@ -31,8 +31,6 @@
 #include "ConfigManager.h"
 #include "embed.h"
 #include "Engine.h"
-#include "Instrument.h"
-#include "InstrumentTrack.h"
 #include "RenameDialog.h"
 #include "Song.h"
 #include "TrackRenameLineEdit.h"
@@ -185,35 +183,6 @@ void TrackLabelButton::mouseReleaseEvent( QMouseEvent *_me )
 
 
 
-void TrackLabelButton::paintEvent( QPaintEvent * _pe )
-{
-	if( m_trackView->getTrack()->type() == Track::Type::Instrument )
-	{
-		auto it = dynamic_cast<InstrumentTrack*>(m_trackView->getTrack());
-		const PixmapLoader * pl;
-		auto get_logo = [](InstrumentTrack* it) -> const PixmapLoader*
-		{
-			return it->instrument()->key().isValid()
-				? it->instrument()->key().logo()
-				: it->instrument()->descriptor()->logo;
-		};
-		if( it && it->instrument() &&
-			it->instrument()->descriptor() &&
-			( pl = get_logo(it) ) )
-		{
-			if( pl->pixmapName() != m_iconName )
-			{
-				m_iconName = pl->pixmapName();
-				setIcon( pl->pixmap() );
-			}
-		}
-	}
-	QToolButton::paintEvent( _pe );
-}
-
-
-
-
 void TrackLabelButton::resizeEvent(QResizeEvent *_re)
 {
 	setText( elideName( m_trackView->getTrack()->displayName() ) );