3 files changed, 137 insertions, 52 deletions

diff --git a/music_sampler/app_blocks/actionlist.py b/music_sampler/app_blocks/actionlist.py
index 70fe3f4..51f4b82 100644
--- a/music_sampler/app_blocks/actionlist.py
+++ b/music_sampler/app_blocks/actionlist.py
@@ -2,13 +2,14 @@ from kivy.uix.label import Label
 from kivy.uix.stacklayout import StackLayout
 from kivy.uix.relativelayout import RelativeLayout
 from kivy.properties import ListProperty, StringProperty
-
-import math
+from ..lock import Lock
 
 __all__ = ["ActionList",
         "ActionListIcons", "ActionListIcon",
         "ActionListDescriptions", "ActionListDescription"]
 
+actionlist_lock = Lock("playlist")
+
 class ActionList(RelativeLayout):
     action_title = StringProperty("")
     action_list = ListProperty([])
@@ -25,7 +26,8 @@ class ActionList(RelativeLayout):
             else:
                 icon = " "
             action_list.append([icon, action])
-        self.action_list = action_list
+        with actionlist_lock:
+            self.action_list = action_list
 
 class ActionListIcons(StackLayout):
     def __init__(self, **kwargs):
@@ -36,13 +38,19 @@ class ActionListIcons(StackLayout):
         parent.bind(action_list=self.update_actionlist_icons)
 
     def update_actionlist_icons(self, instance, actionlist):
-        for icon in self.icons:
-            self.remove_widget(icon)
-        self.icons = []
-        for icon, description in actionlist:
-            icon_label = ActionListIcon(text=icon)
-            self.add_widget(icon_label)
-            self.icons.append(icon_label)
+        icons_length = len(self.icons)
+        index = -1
+        for index, [icon, description] in enumerate(actionlist):
+            if index >= icons_length:
+                icon_label = ActionListIcon(text=icon)
+                self.add_widget(icon_label)
+                self.icons.append(icon_label)
+            else:
+                self.icons[index].text = icon
+
+        if index+1 < icons_length:
+            self.clear_widgets(children=self.icons[index+1:icons_length])
+            del(self.icons[index+1:icons_length])
 
 class ActionListIcon(Label):
     def __init__(self, text='', **kwargs):
@@ -51,8 +59,14 @@ class ActionListIcon(Label):
 
     def on_parent(self, instance, parent):
         if parent is not None:
-            self.font_size = math.ceil(2 * math.sqrt(parent.parent.parent.key_size))
-            self.height = parent.parent.labels_height
+            parent.bind(font_size=self.update_font_size)
+            parent.bind(labels_height=self.update_height)
+
+    def update_height(self, instance, height):
+        self.height = height
+
+    def update_font_size(self, instance, font_size):
+        self.font_size = font_size
 
 class ActionListDescriptions(StackLayout):
     def __init__(self, **kwargs):
@@ -63,13 +77,20 @@ class ActionListDescriptions(StackLayout):
         parent.bind(action_list=self.update_actionlist_descriptions)
 
     def update_actionlist_descriptions(self, instance, actionlist):
-        for description in self.descriptions:
-            self.remove_widget(description)
-        self.descriptions = []
-        for icon, description in actionlist:
-            description_label = ActionListDescription(text=description)
-            self.add_widget(description_label)
-            self.descriptions.append(description_label)
+        descriptions_length = len(self.descriptions)
+        index = -1
+        for index, [icon, description] in enumerate(actionlist):
+            if index >= descriptions_length:
+                description_label = ActionListDescription(text=description)
+                self.add_widget(description_label)
+                self.descriptions.append(description_label)
+            else:
+                self.descriptions[index].text = description
+
+        if index+1 < descriptions_length:
+            self.clear_widgets(
+                    children=self.descriptions[index+1:descriptions_length])
+            del(self.descriptions[index+1:descriptions_length])
 
 class ActionListDescription(Label):
     def __init__(self, text='', **kwargs):
@@ -78,7 +99,12 @@ class ActionListDescription(Label):
 
     def on_parent(self, instance, parent):
         if parent is not None:
-            self.font_size = math.ceil(2 * math.sqrt(parent.parent.parent.key_size))
-            self.height = parent.parent.labels_height
+            parent.bind(font_size=self.update_font_size)
+            parent.bind(labels_height=self.update_height)
+
+    def update_height(self, instance, height):
+        self.height = height
 
+    def update_font_size(self, instance, font_size):
+        self.font_size = font_size
 
diff --git a/music_sampler/app_blocks/playlist.py b/music_sampler/app_blocks/playlist.py
index b704d4d..5894995 100644
--- a/music_sampler/app_blocks/playlist.py
+++ b/music_sampler/app_blocks/playlist.py
@@ -4,14 +4,15 @@ from kivy.uix.relativelayout import RelativeLayout
 from kivy.properties import ListProperty
 from kivy.clock import Clock
 from ..helpers import duration_to_min_sec
-
-import math
+from ..lock import Lock
 
 __all__ = ["PlayList",
         "PlayListIcons", "PlayListIcon",
         "PlayListNames", "PlayListName",
         "PlayListTimes", "PlayListTime"]
 
+playlist_lock = Lock("playlist")
+
 class PlayList(RelativeLayout):
     playlist = ListProperty([])
 
@@ -37,7 +38,8 @@ class PlayList(RelativeLayout):
                 playlist.append(["⏸", music_file.name, time_info, False])
             else:
                 playlist.append(["⏵", music_file.name, time_info, True])
-        self.playlist = playlist
+        with playlist_lock:
+            self.playlist = playlist
 
 
 class PlayListIcons(StackLayout):
@@ -49,13 +51,19 @@ class PlayListIcons(StackLayout):
         parent.bind(playlist=self.update_playlist_icons)
 
     def update_playlist_icons(self, instance, playlist):
-        for icon in self.icons:
-            self.remove_widget(icon)
-        self.icons = []
-        for icon, filename, time_info, playing in playlist:
-            icon_label = PlayListIcon(text=icon)
-            self.add_widget(icon_label)
-            self.icons.append(icon_label)
+        icons_length = len(self.icons)
+        index = -1
+        for index, [icon, filename, time_info, playing] in enumerate(playlist):
+            if index >= icons_length:
+                icon_label = PlayListIcon(text=icon)
+                self.add_widget(icon_label)
+                self.icons.append(icon_label)
+            else:
+                self.icons[index].text = icon
+
+        if index+1 < icons_length:
+            self.clear_widgets(children=self.icons[index+1:icons_length])
+            del(self.icons[index+1:icons_length])
 
 class PlayListIcon(Label):
     def __init__(self, text='', **kwargs):
@@ -64,9 +72,14 @@ class PlayListIcon(Label):
 
     def on_parent(self, instance, parent):
         if parent is not None:
-            self.font_size = math.ceil(2 * math.sqrt(parent.parent.parent.key_size))
-            self.height = parent.parent.labels_height
+            parent.bind(font_size=self.update_font_size)
+            parent.bind(labels_height=self.update_height)
+
+    def update_height(self, instance, height):
+        self.height = height
 
+    def update_font_size(self, instance, font_size):
+        self.font_size = font_size
 
 class PlayListNames(StackLayout):
     def __init__(self, **kwargs):
@@ -77,13 +90,19 @@ class PlayListNames(StackLayout):
         parent.bind(playlist=self.update_playlist_names)
 
     def update_playlist_names(self, instance, playlist):
-        for name in self.names:
-            self.remove_widget(name)
-        self.names = []
-        for icon, filename, time_info, playing in playlist:
-            name_label = PlayListName(text=filename, is_playing=playing)
-            self.add_widget(name_label)
-            self.names.append(name_label)
+        names_length = len(self.names)
+        index = -1
+        for index, [icon, filename, time_info, playing] in enumerate(playlist):
+            if index >= names_length:
+                name_label = PlayListName(text=filename, is_playing=playing)
+                self.add_widget(name_label)
+                self.names.append(name_label)
+            else:
+                self.names[index].text = filename
+
+        if index+1 < names_length:
+            self.clear_widgets(children=self.names[index+1:names_length])
+            del(self.names[index+1:names_length])
 
 class PlayListName(Label):
     def __init__(self, text='', is_playing=False, **kwargs):
@@ -93,8 +112,14 @@ class PlayListName(Label):
 
     def on_parent(self, instance, parent):
         if parent is not None:
-            self.font_size = math.ceil(2 * math.sqrt(parent.parent.parent.key_size))
-            self.height = parent.parent.labels_height
+            parent.bind(font_size=self.update_font_size)
+            parent.bind(labels_height=self.update_height)
+
+    def update_height(self, instance, height):
+        self.height = height
+
+    def update_font_size(self, instance, font_size):
+        self.font_size = font_size
 
 class PlayListTimes(StackLayout):
     def __init__(self, **kwargs):
@@ -105,13 +130,19 @@ class PlayListTimes(StackLayout):
         parent.bind(playlist=self.update_playlist_times)
 
     def update_playlist_times(self, instance, playlist):
-        for time in self.times:
-            self.remove_widget(time)
-        self.times = []
-        for icon, filename, time_info, playing in playlist:
-            time_label = PlayListTime(text=time_info)
-            self.add_widget(time_label)
-            self.times.append(time_label)
+        times_length = len(self.times)
+        index = -1
+        for index, [icon, filename, time_info, playing] in enumerate(playlist):
+            if index >= times_length:
+                time_label = PlayListTime(text=time_info)
+                self.add_widget(time_label)
+                self.times.append(time_label)
+            else:
+                self.times[index].text = time_info
+
+        if index+1 < times_length:
+            self.clear_widgets(children=self.times[index+1:times_length])
+            del(self.times[index+1:times_length])
 
 class PlayListTime(Label):
     def __init__(self, text='', **kwargs):
@@ -120,6 +151,12 @@ class PlayListTime(Label):
 
     def on_parent(self, instance, parent):
         if parent is not None:
-            self.font_size = math.ceil(2 * math.sqrt(parent.parent.parent.key_size))
-            self.height = parent.parent.labels_height
+            parent.bind(font_size=self.update_font_size)
+            parent.bind(labels_height=self.update_height)
+
+    def update_height(self, instance, height):
+        self.height = height
+
+    def update_font_size(self, instance, font_size):
+        self.font_size = font_size
 
diff --git a/music_sampler/music_sampler.kv b/music_sampler/music_sampler.kv
index 4a91896..ffc2797 100644
--- a/music_sampler/music_sampler.kv
+++ b/music_sampler/music_sampler.kv
@@ -204,6 +204,7 @@
 <ActionList>:
   size_hint: None, None
   labels_height: self.parent.max_height or 1
+  font_size: math.ceil(2 * math.sqrt(self.parent.key_size or 10))
   canvas:
     Color:
       rgba: 250./255, 250./255, 250./255, 1
@@ -214,7 +215,7 @@
     id: action_list_title
     font_name: "Ubuntu"
     bold: True
-    font_size: math.ceil(2 * math.sqrt(self.parent.parent.key_size or 10))
+    font_size: self.parent.font_size
     color: 0, 0, 0, 1
     text: self.parent.action_title
     text_size: None, self.parent.height
@@ -223,15 +224,21 @@
     size_hint: None, None
     size: self.texture_size[0], self.parent.height
   ActionListIcons:
+    font_size: self.parent.font_size
+    labels_height: self.parent.labels_height
     orientation: 'lr-tb'
     size_hint: 0.02, 0.9
     pos_hint: { 'x': 0, 'top': 0.9 }
   ActionListDescriptions:
+    font_size: self.parent.font_size
+    labels_height: self.parent.labels_height
     orientation: 'lr-tb'
     size_hint: 0.98, 0.9
     pos_hint: { 'x': 0.02, 'top': 0.9 }
 
 <ActionListIcon>:
+  font_size: self.parent and self.parent.font_size or 10
+  height: self.parent and self.parent.labels_height or 0
   font_name: "Symbola"
   color: 0, 0, 0, 1
   text_size: None, None
@@ -240,6 +247,8 @@
   width: self.texture_size[0]
 
 <ActionListDescription>:
+  font_size: self.parent and self.parent.font_size or 10
+  height: self.parent and self.parent.labels_height or 0
   font_name: "Ubuntu"
   color: 0, 0, 0, 1
   text_size: self.width, None
@@ -252,6 +261,7 @@
 <PlayList>:
   size_hint: None, None
   labels_height: self.parent.max_height or 1
+  font_size: math.ceil(2 * math.sqrt(self.parent.key_size or 10))
   canvas:
     Color:
       rgba: 250./255, 250./255, 250./255, 1
@@ -259,19 +269,27 @@
       pos:  0, 0
       size: self.width, self.height
   PlayListIcons:
+    font_size: self.parent.font_size
+    labels_height: self.parent.labels_height
     orientation: 'lr-tb'
     size_hint: 0.05, 1
     pos_hints: { 'x': 0, 'top': 0 }
   PlayListNames:
+    font_size: self.parent.font_size
+    labels_height: self.parent.labels_height
     orientation: 'lr-tb'
     pos_hint: { 'x': 0.05, 'bottom': 0 }
     size_hint: 0.65, 1
   PlayListTimes:
+    font_size: self.parent.font_size
+    labels_height: self.parent.labels_height
     orientation: 'lr-tb'
     pos_hint: { 'x': 0.7, 'bottom': 0 }
     size_hint: 0.30, 1
  
 <PlayListIcon>:
+  font_size: self.parent and self.parent.font_size or 10
+  height: self.parent and self.parent.labels_height or 0
   font_name: "Symbola"
   color: 0, 0, 0, 1
   text_size: None, None
@@ -280,6 +298,8 @@
   width: self.texture_size[0]
 
 <PlayListName>:
+  font_size: self.parent and self.parent.font_size or 10
+  height: self.parent and self.parent.labels_height or 0
   font_name: "Ubuntu"
   color: 0, 0, 0, 1
   text_size: self.width, None
@@ -290,6 +310,8 @@
   size_hint: 1, None
 
 <PlayListTime>:
+  font_size: self.parent and self.parent.font_size or 10
+  height: self.parent and self.parent.labels_height or 0
   canvas.before:
     Color:
       rgba: 250./255, 250./255, 250./255, 1