Add Audio-device listing support for alsa-pcm

Added a AlsaDeviceListModel, will do the same for other devices as well

data/themes/default/style.css

@@ -107,7 +107,7 @@ trackWidget {
 /*	border-bottom: 1px solid rgb(0, 0, 0);*/
 	background-color: rgb(0, 0, 0);
 }
-nameLabel, effectLabel, sf2InstrumentView > QLabel {
+nameLabel, effectLabel, sf2InstrumentView > QLabel, QComboBox {
 	font-size:10px;
 }
 

include/AudioAlsa.h

@@ -35,10 +35,11 @@
 #include <alsa/asoundlib.h>
 
 #include "AudioDevice.h"
+#include "QAbstractListModel"
 
 
 class lcdSpinBox;
-class QLineEdit;
+class QComboBox;
 
 
 class AudioAlsa : public AudioDevice, public QThread
@@ -54,6 +55,23 @@ public:
 	}
 
 	static QString probeDevice();
+	
+
+	class DeviceListModel : public QAbstractListModel
+	{
+	public:
+		// iface = {"pcm", "rawmidi", "timer", "seq"}
+		// stream =  {SND_PCM_STREAM_CAPTURE, SND_PCM_STREAM_PLAYBACK}
+		DeviceListModel( const char * _iface, snd_pcm_stream_t stream );
+
+		int rowCount( const QModelIndex & parent = QModelIndex() ) const;
+		QVariant data( const QModelIndex & index,
+		               int role = Qt::DisplayRole ) const;
+	private:
+		typedef QPair<QString,QString> StringPair;
+		typedef QList<StringPair> DeviceList;
+		DeviceList m_devices;
+	};
 
 
 	class setupWidget : public AudioDevice::setupWidget
@@ -65,9 +83,14 @@ public:
 		virtual void saveSettings();
 
 	private:
-		QLineEdit * m_device;
+		QComboBox * m_device;
 		lcdSpinBox * m_channels;
 
+		void poo(const QString & s)
+		{
+			printf("Got %s\n", qPrintable( s ) );
+		}
+
 	} ;
 
 

src/core/audio/AudioAlsa.cpp

@@ -22,7 +22,7 @@
  *
  */
 
-#include <QtGui/QLineEdit>
+#include <QtGui/QComboBox>
 #include <QtGui/QLabel>
 
 #include "AudioAlsa.h"
@@ -491,16 +491,87 @@ int AudioAlsa::setSWParams()
 
 
 
+AudioAlsa::DeviceListModel::DeviceListModel(
+		const char * _iface, snd_pcm_stream_t _stream )
+{
+	void **hints, **n;
+	char *name, *descr, *io;
+	const char *filter;
+
+	if (snd_device_name_hint(-1, _iface, &hints) < 0)
+		return;
+	n = hints;
+	filter = _stream == SND_PCM_STREAM_CAPTURE ? "Input" : "Output";
+	while (*n != NULL) {
+		name = snd_device_name_get_hint(*n, "NAME");
+		descr = snd_device_name_get_hint(*n, "DESC");
+		io = snd_device_name_get_hint(*n, "IOID");
+		
+		// Filter out non-null or filtered items
+		if (io != NULL && strcmp(io, filter) != 0)
+			continue;
+
+		m_devices.append(StringPair(name, descr));
+		if (name != NULL)
+			free(name);
+		if (descr != NULL)
+			free(descr);
+		if (io != NULL)
+			free(io);
+		n++;
+	}
+	snd_device_name_free_hint(hints);
+}
+
+
+
+int AudioAlsa::DeviceListModel::rowCount(
+		const QModelIndex & parent ) const
+{
+	return m_devices.count();
+}
+
+
+
+QVariant AudioAlsa::DeviceListModel::data(
+		const QModelIndex & index,
+		int role ) const
+{
+	switch( role )
+	{
+	case Qt::DisplayRole:
+		return m_devices.at(index.row()).first;
+	case Qt::ToolTipRole:
+	case Qt::StatusTipRole:
+		return m_devices.at(index.row()).second;
+	default:
+		return QVariant();
+	};
+}
+
+
+
 
 AudioAlsa::setupWidget::setupWidget( QWidget * _parent ) :
 	AudioDevice::setupWidget( AudioAlsa::name(), _parent )
 {
-	m_device = new QLineEdit( AudioAlsa::probeDevice(), this );
-	m_device->setGeometry( 10, 20, 160, 20 );
+
+	m_device = new QComboBox( this );
+	m_device->setGeometry( 10, 20, 180, 20 );
+	m_device->setModel(
+			new DeviceListModel( "pcm", SND_PCM_STREAM_PLAYBACK ) );
+	m_device->setEditable( true );
+	m_device->setInsertPolicy( QComboBox::NoInsert );
+	m_device->setEditText( AudioAlsa::probeDevice() );
+
+	// Why doesn't Qt already do this?
+	connect( m_device, SIGNAL(currentIndexChanged(const QString &)),
+			this, SLOT(poo(const QString &)) );
+
 
 	QLabel * dev_lbl = new QLabel( tr( "DEVICE" ), this );
 	dev_lbl->setFont( pointSize<6>( dev_lbl->font() ) );
-	dev_lbl->setGeometry( 10, 40, 160, 10 );
+	dev_lbl->setGeometry( 10, 40, 180, 10 );
 
 	lcdSpinBoxModel * m = new lcdSpinBoxModel( /* this */ );
 	m->setRange( DEFAULT_CHANNELS, SURROUND_CHANNELS );
@@ -511,7 +582,7 @@ AudioAlsa::setupWidget::setupWidget( QWidget * _parent ) :
 	m_channels = new lcdSpinBox( 1, this );
 	m_channels->setModel( m );
 	m_channels->setLabel( tr( "CHANNELS" ) );
-	m_channels->move( 180, 20 );
+	m_channels->move( 200, 20 );
 
 }
 
@@ -529,7 +600,7 @@ AudioAlsa::setupWidget::~setupWidget()
 void AudioAlsa::setupWidget::saveSettings()
 {
 	configManager::inst()->setValue( "audioalsa", "device",
-							m_device->text() );
+							m_device->currentText() );
 	configManager::inst()->setValue( "audioalsa", "channels",
 				QString::number( m_channels->value<int>() ) );
 }