implement MPRIS SetVolume

backend/mpris.go

@@ -59,6 +59,11 @@ func NewMPRISHandler(playerName string, p *player.Player, pm *PlaybackManager) *
 			m.evt.Player.OnTitle()
 		}
 	})
+	m.pm.OnVolumeChange(func(vol int) {
+		if m.connErr == nil {
+			m.evt.Player.OnVolume()
+		}
+	})
 	emitPlayStatus := func() {
 		if m.connErr == nil {
 			m.evt.Player.OnPlayPause()
@@ -253,8 +258,8 @@ func (m *MPRISHandler) Volume() (float64, error) {
 	return float64(m.p.GetVolume()) / 100, nil
 }
 
-func (m *MPRISHandler) SetVolume(float64) error {
-	return errNotImplemented
+func (m *MPRISHandler) SetVolume(v float64) error {
+	return m.pm.SetVolume(int(v * 100))
 }
 
 func (m *MPRISHandler) Position() (int64, error) {

backend/playbackmanager.go

@@ -49,6 +49,7 @@ type PlaybackManager struct {
 	onSongChange     []func(nowPlaying, justScrobbledIfAny *mediaprovider.Track)
 	onPlayTimeUpdate []func(float64, float64)
 	onLoopModeChange []func(LoopMode)
+	onVolumeChange   []func(int)
 }
 
 func NewPlaybackManager(
@@ -142,6 +143,11 @@ func (p *PlaybackManager) OnLoopModeChange(cb func(LoopMode)) {
 	p.onLoopModeChange = append(p.onLoopModeChange, cb)
 }
 
+// Registers a callback that is notified whenever the volume changes.
+func (p *PlaybackManager) OnVolumeChange(cb func(int)) {
+	p.onVolumeChange = append(p.onVolumeChange, cb)
+}
+
 // Loads the specified album into the play queue.
 func (p *PlaybackManager) LoadAlbum(albumID string, appendToQueue bool, shuffle bool) error {
 	album, err := p.sm.Server.GetAlbum(albumID)
@@ -335,6 +341,21 @@ func (p *PlaybackManager) LoopMode() LoopMode {
 	return LoopMode(p.player.GetLoopMode())
 }
 
+func (p *PlaybackManager) SetVolume(vol int) error {
+	vol = clamp(vol, 0, 100)
+	if err := p.player.SetVolume(vol); err != nil {
+		return err
+	}
+	for _, cb := range p.onVolumeChange {
+		cb(vol)
+	}
+	return nil
+}
+
+func (p *PlaybackManager) Volume() int {
+	return p.player.GetVolume()
+}
+
 // call BEFORE updating p.nowPlayingIdx
 func (p *PlaybackManager) checkScrobble() {
 	if !p.scrobbleCfg.Enabled || len(p.playQueue) == 0 || p.nowPlayingIdx < 0 {

ui/bottompanel.go

@@ -54,9 +54,7 @@ func NewBottomPanel(p *player.Player, pm *backend.PlaybackManager, contr *contro
 	p.OnStopped(func() {
 		bp.Controls.SetPlaying(false)
 	})
-	pm.OnLoopModeChange(func(mode backend.LoopMode) {
-		bp.AuxControls.SetLoopMode(mode)
-	})
+	pm.OnLoopModeChange(bp.AuxControls.SetLoopMode)
 
 	bp.NowPlaying = widgets.NewNowPlayingCard()
 	bp.NowPlaying.OnShowCoverImage = func() {
@@ -100,8 +98,9 @@ func NewBottomPanel(p *player.Player, pm *backend.PlaybackManager, contr *contro
 	})
 
 	bp.AuxControls = widgets.NewAuxControls(p.GetVolume())
-	bp.AuxControls.VolumeControl.OnVolumeChanged = func(v int) {
-		_ = p.SetVolume(v)
+	pm.OnVolumeChange(bp.AuxControls.VolumeControl.SetVolume)
+	bp.AuxControls.VolumeControl.OnSetVolume = func(v int) {
+		_ = bp.playbackManager.SetVolume(v)
 	}
 	bp.AuxControls.OnChangeLoopMode(func() {
 		bp.playbackManager.SetNextLoopMode()

ui/mainwindow.go

@@ -163,15 +163,15 @@ func (m *MainWindow) SetupSystemTrayMenu(appName string, fyneApp fyne.App) {
 			}),
 			fyne.NewMenuItemSeparator(),
 			fyne.NewMenuItem("Volume +10%", func() {
-				vol := m.App.Player.GetVolume()
+				vol := m.App.PlaybackManager.Volume()
 				vol = vol + int(float64(vol)*0.1)
 				// will clamp to range for us
-				m.BottomPanel.AuxControls.VolumeControl.SetVolume(vol)
+				m.App.PlaybackManager.SetVolume(vol)
 			}),
 			fyne.NewMenuItem("Volume -10%", func() {
-				vol := m.App.Player.GetVolume()
+				vol := m.App.PlaybackManager.Volume()
 				vol = vol - int(float64(vol)*0.1)
-				m.BottomPanel.AuxControls.VolumeControl.SetVolume(vol)
+				m.App.PlaybackManager.SetVolume(vol)
 			}),
 			fyne.NewMenuItemSeparator(),
 			fyne.NewMenuItem("Show", m.Window.Show),

ui/widgets/auxcontrols.go

@@ -162,7 +162,7 @@ type VolumeControl struct {
 	icon   *TappableIcon
 	slider *volumeSlider
 
-	OnVolumeChanged func(int)
+	OnSetVolume func(int)
 
 	muted   bool
 	lastVol int
@@ -185,24 +185,35 @@ func NewVolumeControl(initialVol int) *VolumeControl {
 	return v
 }
 
+// Sets the volume that is displayed in the slider.
+// Does not invoke OnSetVolume callback.
+func (v *VolumeControl) SetVolume(vol int) {
+	if (vol == v.lastVol && !v.muted) || (v.muted && vol == 0) {
+		return
+	}
+	v.lastVol = vol
+	v.muted = false
+	v.setDisplayedVolume(vol)
+}
+
 func (v *VolumeControl) onChanged(volume float64) {
 	vol := int(volume)
 	v.lastVol = vol
 	v.muted = false
 	v.updateIconForVolume(vol)
-	if v.OnVolumeChanged != nil {
-		v.OnVolumeChanged(vol)
-	}
+	v.invokeOnVolumeChange(vol)
 }
 
 func (v *VolumeControl) toggleMute() {
 	if !v.muted {
 		v.muted = true
 		v.lastVol = int(v.slider.Value)
-		v.SetVolume(0)
+		v.setDisplayedVolume(0)
+		v.invokeOnVolumeChange(0)
 	} else {
 		v.muted = false
-		v.SetVolume(v.lastVol)
+		v.setDisplayedVolume(v.lastVol)
+		v.invokeOnVolumeChange(v.lastVol)
 	}
 }
 
@@ -211,12 +222,15 @@ func (v *VolumeControl) CreateRenderer() fyne.WidgetRenderer {
 	return widget.NewSimpleRenderer(v.container)
 }
 
-func (v *VolumeControl) SetVolume(vol int) {
+func (v *VolumeControl) setDisplayedVolume(vol int) {
 	v.slider.Value = float64(vol)
 	v.slider.Refresh()
 	v.updateIconForVolume(vol)
-	if v.OnVolumeChanged != nil {
-		v.OnVolumeChanged(vol)
+}
+
+func (v *VolumeControl) invokeOnVolumeChange(vol int) {
+	if v.OnSetVolume != nil {
+		v.OnSetVolume(vol)
 	}
 }