Set "song modified" flag in core

Move setting the song to modified towards the core in the context of `SampleClip`. Previously the `SampleClipView` did this but it's none of it's business.

Introduce `SampleClip::changeLengthToSampleLength` which changes the length of the clip to the length of the sample. This was also previously done by the view which is again the wrong place to do the necessary calculations.

include/SampleClip.h

@@ -55,6 +55,7 @@ class SampleClip : public Clip
 	SampleClip& operator=( const SampleClip& that ) = delete;
 
 	void changeLength( const TimePos & _length ) override;
+	void changeLengthToSampleLength();
 	const QString& sampleFile() const;
 
 	void saveSettings( QDomDocument & _doc, QDomElement & _parent ) override;

src/core/SampleClip.cpp

@@ -112,6 +112,11 @@ void SampleClip::changeLength( const TimePos & _length )
 	Clip::changeLength(std::max(static_cast<int>(_length), 1));
 }
 
+void SampleClip::changeLengthToSampleLength()
+{
+	int length = static_cast<int>(m_sample.sampleSize() / Engine::framesPerTick());
+	changeLength(length);
+}
 
 
 
@@ -129,6 +134,8 @@ void SampleClip::setSampleBuffer(std::shared_ptr<const SampleBuffer> sb)
 	updateLength();
 
 	emit sampleChanged();
+
+	Engine::getSong()->setModified();
 }
 
 void SampleClip::setSampleFile(const QString& sf)
@@ -210,6 +217,8 @@ void SampleClip::setIsPlaying(bool isPlaying)
 void SampleClip::updateLength()
 {
 	emit sampleChanged();
+
+	Engine::getSong()->setModified();
 }
 
 

src/gui/clips/SampleClipView.cpp

@@ -128,7 +128,6 @@ void SampleClipView::dropEvent( QDropEvent * _de )
 		m_clip->updateLength();
 		update();
 		_de->accept();
-		Engine::getSong()->setModified();
 	}
 	else
 	{
@@ -190,8 +189,7 @@ void SampleClipView::mouseDoubleClickEvent( QMouseEvent * )
 	if (af == m_clip->m_sample.sampleFile())
 	{
 		// Don't reload the same file again. Just reset the size.
-		int length = static_cast<int>(m_clip->m_sample.sampleSize() / Engine::framesPerTick());
-		m_clip->changeLength(length);
+		m_clip->changeLengthToSampleLength();
 	}
 	else
 	{
@@ -200,9 +198,6 @@ void SampleClipView::mouseDoubleClickEvent( QMouseEvent * )
 		if (sampleBuffer != SampleBuffer::emptyBuffer())
 		{
 			m_clip->setSampleBuffer(sampleBuffer);
-
-			// TODO Why do we have to do this here? This should happen in the core...
-			Engine::getSong()->setModified();
 		}
 	}
 }