Can't reset the media without re-initializing the media player

[moham96]

Hi,

I want to use the event manager to play the next item of a list but only the first item is being played,
to get the rest of the list to play i need to re initialize the media player object every time I set the new media

import vlc
import time

class player:
	def __init__(self):
		self.items = ['/home/mohammad/foo.wav',
		'/home/mohammad/bar.wav',
		'/home/mohammad/egg.wav']
		self.libvlc_Instance = vlc.Instance('--verbose 2')
		self.libvlc_player = self.libvlc_Instance.media_player_new()

	def play_next(self,num):
		self.play_item(num)

	def play_item(self,num=0):
		print(num)

		self.libvlc_player_event_manager = self.libvlc_player.event_manager()
		self.libvlc_list_player = self.libvlc_Instance.media_list_player_new()
		self.libvlc_Media_list = self.libvlc_Instance.media_list_new()
		self.libvlc_list_player.set_media_player(self.libvlc_player)
		media=self.libvlc_Instance.media_new(self.items[num])
		self.libvlc_Media_list.add_media(media)
		self.libvlc_list_player.set_media_list(self.libvlc_Media_list)
		self.libvlc_list_player.play_item(media)
		if num < len(self.items)-1:
			self.libvlc_player_event_manager.event_attach(
				vlc.EventType.MediaPlayerEndReached, lambda event :self.play_next(num+1))

	def is_playing(self):
		if self.libvlc_player.get_state()==vlc.State.Opening or self.libvlc_player.get_state()== vlc.State.Playing:
			return True

mpl=player()
mpl.play_item(0)

while mpl.is_playing():
	time.sleep(1)

so the above code plays the first item and then exits, but if i move the line where i create the media player object to inside the play_item function (so the object get's created every time) the code wil work and items will be played sequentially, like so:

import vlc
import time

class player:
	def __init__(self):
		self.items = ['/home/mohammad/foo.wav',
		'/home/mohammad/bar.wav',
		'/home/mohammad/egg.wav']
		self.libvlc_Instance = vlc.Instance('--verbose 2')


	def play_next(self,num):
		self.play_item(num)

	def play_item(self,num=0):
		print(num)
		self.libvlc_player = self.libvlc_Instance.media_player_new()
		self.libvlc_player_event_manager = self.libvlc_player.event_manager()
		self.libvlc_list_player = self.libvlc_Instance.media_list_player_new()
		self.libvlc_Media_list = self.libvlc_Instance.media_list_new()
		self.libvlc_list_player.set_media_player(self.libvlc_player)
		media=self.libvlc_Instance.media_new(self.items[num])
		self.libvlc_Media_list.add_media(media)
		self.libvlc_list_player.set_media_list(self.libvlc_Media_list)
		self.libvlc_list_player.play_item(media)
		if num < len(self.items)-1:
			self.libvlc_player_event_manager.event_attach(
				vlc.EventType.MediaPlayerEndReached, lambda event :self.play_next(num+1))

	def is_playing(self):
		if self.libvlc_player.get_state()==vlc.State.Opening or self.libvlc_player.get_state()== vlc.State.Playing:
			return True

mpl=player()
mpl.play_item(0)

while mpl.is_playing():
	time.sleep(1)

So why can't I use the same media player and change the media ?!

[oaubert]

I see two things here:

• your code seem fairly convoluted. Here is a simple version of a player playing a list of items:

``
#! /usr/bin/env python3

import code
import vlc

player = vlc.MediaListPlayer()

sounds = player.get_instance().media_list_new(("/usr/share/psi-plus/sound/attention.wav",
"/usr/share/psi-plus/sound/chat1.wav",
"/usr/share/psi-plus/sound/chat2.wav",
"/usr/share/psi-plus/sound/chess_error.wav"))
player.set_media_list(sounds)
player.play()
code.interact(local=locals())
``

• the event handlers are not re-entrant. That means that you cannot call the libvlc API directly from an event handler, you need to delegate this to some mainloop of your application.

[moham96]

@oaubert well the thing is the code I put doesn't reflect what I'm doing, instead, I made up the above code to explain the problem I am having.
What I'm trying to do is to use gmusicapi with VLC. If you are not familiar with this library it generates URLs for the songs that are in your google music library.
So, I don't have a prepared list of items to pass to the media list player,
instead, Each time the playing song reaches the end and invoke the callback function, the callback function would fetch the URL of the song and pass it to the player

from gmusicapi import Mobileclient
import vlc
import json
import time
import os
import sys

USER_AGENT = ' '.join([
    'Mozilla/5.0 (X11; Linux x86_64)'
    'AppleWebKit/537.36 (KHTML, like Gecko)'
    'Chrome/62.0.3202.94 Safari/537.36'
])

class sampleplayer():
	def __init__(self):
		self.libvlc_Instance = vlc.Instance('--verbose 2')
		self.libvlc_Instance.set_user_agent('My own player', USER_AGENT)
		self.libvlc_player = self.libvlc_Instance.media_player_new()
		self.libvlc_list_player = self.libvlc_Instance.media_list_player_new()
		self.libvlc_Media_list = self.libvlc_Instance.media_list_new()
		self.libvlc_list_player.set_media_player(self.libvlc_player)
		self.libvlc_list_player.set_media_list(self.libvlc_Media_list)
		self.libvlc_player_event_manager = self.libvlc_player.event_manager()
		self.api = Mobileclient()
		self.api.login(email, password,
			Mobileclient.FROM_MAC_ADDRESS)

	def loadplaylist(self,playlistnum):
	    track_ids = []
	    if os.path.isfile(os.path.expanduser("~/playlist.json")):
	        with open(os.path.expanduser('~/playlist.json'), 'r') as input_file:
	            playlistcontents = json.load(input_file)
	    else:
	        playlistcontents = self.api.get_all_user_playlist_contents()
	        with open(os.path.expanduser('~/playlist.json'), 'w') as output_file:
	            json.dump(playlistcontents, output_file)
	        print(playlistcontents[0])
	    for i in playlistcontents[playlistnum]['tracks']:
	        track_ids.append(i['trackId'])
	    return track_ids

	def play_next(self,num):
		print('playing next')
		self.play_item(num)

	def play_item(self,num=0):
	    tracks=self.loadplaylist(1)
	    print(tracks)
	    print(num)
	    url=self.api.get_stream_url(tracks[num])
	    media = self.libvlc_Instance.media_new(url)
	    self.libvlc_Media_list.add_media(media)
	    print(url)
	    self.libvlc_player.set_media(media)
	    self.libvlc_list_player.play()

	    if num < len(tracks)-1:
	        print('hooking event ')
	        self.libvlc_player_event_manager.event_attach(
	        	vlc.EventType.MediaPlayerEndReached, lambda event:self.play_next(num+1))

player=sampleplayer()

player.play_item(0)

while True:
	time.sleep(10)

Regarding your second point do you mean I should make a loop to check libvlc_player.get_state() and when it is equal to vlc.State.Ended I can play the next item? If my understanding is wrong could you elaborate and give an example?