def next_list(self):
""" Each time this func is invoked, a next pagination of tracks is loaded
Then self.get_cur_tracks should be called to retrieve the current list of tracks
@return bool: True if this new pagination still contains tracks,
False if no more tracks, i.e. last pagination
None if something wrong with the station, e.g. incorrect stationId
"""
self.__curStartIdx += self.__prevItems
self.__prevItems = 0
self.__curThumbUpTracks = []
url = self.STATION_TRACKS_BASE_URL
url = url.replace("[stationId]", self.__stationId)
url = url.replace("[startIdx]", str(self.__curStartIdx))
try:
response = urllib2.urlopen(url)
except:
# there must be something wrong with the url, i.e. incorrect url
return None
html = response.read()
elements = DOM.get_elements("li", {"data-date": "[0-9]+", "data-artist": "[^>]+"}, html)
for e in elements:
trackNodes = DOM.get_elements("h3", {}, e.nodeValue)
if len(trackNodes)==0:
continue
trackNode = trackNodes[0]
songNodes = DOM.get_elements("a", {}, trackNode.nodeValue)
if len(songNodes)<2:
continue
song = String.decode_html_entities(songNodes[0].nodeValue)
song = String.symbols_to_words(song)
song = self.__remove_redundant_words(song)
artist = String.decode_html_entities(songNodes[1].nodeValue)
artist = String.symbols_to_words(artist)
record = song+' '+artist
if not record in self.__thumbUpTracks:
self.__thumbUpTracks.append(record)
self.__curThumbUpTracks.append(record)
self.__prevItems += 1
if self.__prevItems == 0:
return False
return True
