added shuffle button to UI + base data flow

backend/playbackengine.go

@@ -263,6 +263,15 @@ func (p *playbackEngine) GetLoopMode() LoopMode {
 	return p.loopMode
 }
 
+func (p *playbackEngine) SetShuffle(shuffle bool) {
+	p.shuffle = shuffle
+	//TODO: Implement functionality
+}
+
+func (p *playbackEngine) GetShuffle() bool {
+	return p.shuffle
+}
+
 func (p *playbackEngine) PlaybackStatus() PlaybackStatus {
 	stat := p.pendingPlayerChangeStatus
 	if !p.pendingPlayerChange {

backend/playbackmanager.go

@@ -373,6 +373,10 @@ func (p *PlaybackManager) LoadAlbum(albumID string, insertQueueMode InsertQueueM
 	return nil
 }
 
+func (p *PlaybackManager) GetShuffle() bool {
+	return p.engine.GetShuffle()
+}
+
 // Loads the specified playlist into the play queue.
 func (p *PlaybackManager) LoadPlaylist(playlistID string, insertQueueMode InsertQueueMode, shuffle bool) error {
 	playlist, err := p.engine.sm.Server.GetPlaylist(playlistID)
@@ -639,6 +643,10 @@ func (p *PlaybackManager) SetAutoplay(autoplay bool) {
 	}
 }
 
+func (p *PlaybackManager) SetShuffle(shuffle bool) {
+	p.engine.SetShuffle(shuffle)
+}
+
 func (p *PlaybackManager) Volume() int {
 	return p.engine.CurrentPlayer().GetVolume()
 }

ui/bottompanel.go

@@ -122,6 +122,9 @@ func NewBottomPanel(pm *backend.PlaybackManager, im *backend.ImageManager, contr
 	bp.AuxControls.OnChangeAutoplay = func(autoplay bool) {
 		pm.SetAutoplay(autoplay)
 	}
+	bp.AuxControls.OnChangeShuffle = func(shuffle bool) {
+		pm.SetShuffle(shuffle)
+	}
 	bp.AuxControls.OnShowPlayQueue(contr.ShowPopUpPlayQueue)
 	bp.AuxControls.OnShowCastMenu(contr.ShowCastMenu)
 

ui/widgets/auxcontrols.go

@@ -111,11 +111,11 @@ func (a *AuxControls) SetLoopMode(mode backend.LoopMode) {
 }
 
 func (a *AuxControls) SetShuffle(isShuffle bool) {
-	if isShuffle {
-		a.shuffle.Highlighted = true
-	} else {
-		a.shuffle.Highlighted = false
+	if isShuffle == a.shuffle.Highlighted {
+		return
 	}
+	a.shuffle.Highlighted = isShuffle
+	a.shuffle.Refresh()
 }
 
 func (a *AuxControls) DisableCastButton() {