add remove from playlist support

ui/browsing/playlistpage.go

@@ -50,6 +50,9 @@ func NewPlaylistPage(
 	a.header = NewPlaylistPageHeader(a)
 	a.tracklist = widgets.NewTracklist(nil)
 	a.tracklist.AutoNumber = true
+	a.tracklist.AuxiliaryMenuItems = []*fyne.MenuItem{
+		fyne.NewMenuItem("Remove from playlist", a.onRemoveSelectedFromPlaylist),
+	}
 	// connect tracklist actions
 	a.tracklist.OnPlayTrackAt = a.onPlayTrackAt
 	a.tracklist.OnAddToQueue = func(tracks []*subsonic.Child) { a.pm.LoadTracks(tracks, true) }
@@ -114,6 +117,11 @@ func (a *PlaylistPage) loadAsync() {
 	}()
 }
 
+func (a *PlaylistPage) onRemoveSelectedFromPlaylist() {
+	a.sm.Server.UpdatePlaylistTracks(a.playlistID, nil, a.tracklist.SelectedTrackIndexes())
+	go a.Reload()
+}
+
 type PlaylistPageHeader struct {
 	widget.BaseWidget
 

ui/widgets/tracklist.go

@@ -112,6 +112,8 @@ type Tracklist struct {
 
 	Tracks     []*subsonic.Child
 	AutoNumber bool
+	// must be set before the context menu is shown for the first time
+	AuxiliaryMenuItems []*fyne.MenuItem
 
 	// user action callbacks
 	OnPlayTrackAt   func(int)
@@ -219,6 +221,10 @@ func (t *Tracklist) onShowContextMenu(e *fyne.PointEvent, trackIdx int) {
 				}
 			}),
 		)
+		if len(t.AuxiliaryMenuItems) > 0 {
+			t.ctxMenu.Items = append(t.ctxMenu.Items, fyne.NewMenuItemSeparator())
+			t.ctxMenu.Items = append(t.ctxMenu.Items, t.AuxiliaryMenuItems...)
+		}
 	}
 	widget.ShowPopUpMenuAtPosition(t.ctxMenu, fyne.CurrentApp().Driver().CanvasForObject(t), e.AbsolutePosition)
 }
@@ -240,3 +246,7 @@ func (t *Tracklist) selectedTrackIDs() []string {
 	}
 	return tracks
 }
+
+func (t *Tracklist) SelectedTrackIndexes() []int {
+	return t.selectionMgr.GetSelection()
+}