Loading screen

Author: intendednull

src/cache.py

@@ -72,11 +72,14 @@ def mainloop(self, queue):
             profile = self.get_profile()
             if profile is not None:
                 queue.put(profile)
-            time.sleep(self.ratelimit)
+            time.sleep(5)
 
     def next(self):
         return self.queue.get()
 
+    def ready(self):
+        return not self.queue.empty()
+
     def start(self):
         if self.worker is not None and self.worker.is_alive():
             self.stop()

src/front.py

@@ -7,6 +7,7 @@
 from .cache import ImageCache
 from .loading import Loading
 
+
 def process_image(image: bytes, width: int, height: int):
     im = Image.open(io.BytesIO(image))
     im = im.resize((width, height), Image.NEAREST)
@@ -23,19 +24,27 @@ class Front(widget.PrimaryFrame):
     _last = None
 
     def __next(self, direction: Direction = None):
-        data: dict = self.cache.next()
-        image = process_image(
-            data.pop('image'),
-            self.window.winfo_width(),
-            self.window.winfo_height()
-        )
-        name = data.pop('name')
-        self.__load(name, image, data)
-        if direction is None:
-            self.window.set_view(self.image)
-        else:
+        if self.cache.ready():
+            data: dict = self.cache.next()
+            image = process_image(
+                data.pop('image'),
+                self.window.winfo_width(),
+                self.window.winfo_height()
+            )
+            name = data.pop('name')
+            self.__load(name, image, data)
             self.window.change_view(self.image, direction)
 
+        else:
+            loadscreen = Loading(
+                self.window,
+                width=self.window.winfo_width(),
+                height=self.window.winfo_height()
+            )
+            self.window.change_view(View(loadscreen, 'widget'), direction)
+            loadscreen.waitfor(self.cache.ready, self.__next, ('up',))
+            self.update()
+
     def __load(self, name, image, data):
         self.title.config(text=name)
         self.image = View(image, 'image')
@@ -72,6 +81,8 @@ def init(self):
 
         self.cache = ImageCache(self.cachesize)
         self.cache.start()
+
+    def start(self):
         self.after(0, self.__next)
 
     def cmd_dislike(self):

src/loading.py

@@ -1,30 +1,36 @@
-from PIL import Image, ImageTk
 from time import sleep
+from PIL import Image, ImageTk
 from contextlib import suppress
 from itertools import cycle
+from typing import Callable
 
-from .widget import SecondaryCanvas
+from .widget import PrimaryCanvas
 from . import IMAGES
 
+
 def generate_frames(im: Image):
     with suppress(EOFError):
         while True:
             im.seek(im.tell()+1)
             yield ImageTk.PhotoImage(im)
 
-class Loading(SecondaryCanvas):
-    frames = generate_frames(Image.open(IMAGES / "loading.gif"))
-    active = True
+
+class Loading(PrimaryCanvas):
+    image = IMAGES / "loading.gif"
     last = 0
+    limit = 1 / 20
+
+    def init(self):
+        self.frames = generate_frames(Image.open(self.image))
 
-    def start(self):
+    def waitfor(self, condition: Callable, cmd: Callable = None, args=()):
         for im in cycle(self.frames):
-            if not self.active:
+            if condition():
+                if cmd is not None:
+                    cmd(*args)
                 break
             if self.last:
                 self.delete(self.last)
             self.last = self.create_image(0, 0, image=im, anchor='nw')
             self.update()
-
-    def stop(self):
-        self.active = False
+            sleep(self.limit)

src/main.py

@@ -24,8 +24,8 @@ def __init__(self, *args, **kwds):
         self.maxsize(400, 500)
 
         self.front = Front(self)
-
         self.front.pack(fill='both', expand=True)
+        self.front.start()
 
     def cleanup(self):
         self.front.cleanup()

src/view.py

@@ -79,7 +79,10 @@ def move_out(self, view: View, direction: Direction):
         self.move_view(view, end)
         del self.views[view]
 
-    def change_view(self, view: View, direction: Direction):
+    def change_view(self, view: View, direction: Direction = None):
+        if direction is None:
+            self.set_view(view)
+            return
         if not isinstance(direction, Direction):
             direction = Direction[direction.upper()]  # Cast string for convenience
         self.animater.clear()