add loading icon

flash.py

@@ -1,20 +1,24 @@
 #!/usr/bin/env python3
 
+import threading
+import loader
+from queue import Queue
 import subprocess
 import time
 import fourletterphat as flp
 
 #--
-drive_blacklist = {"/boot","/"}
+q = Queue()
+t = loader.bgload(3, .1)
 #--
 
 def disp_string(string):
-    for letter in range(0,4):
+    for letter in range(0,3) if len(string) > 3 else range(0, len(string)):
         try:
             flp.set_digit(letter, string[letter].upper())
         except IndexError:
             pass
-    flp.show()
+        flp.show()
 
 def get_mountedlist():
     return [item[item.find("/"):] for item in subprocess.check_output(
@@ -31,16 +35,24 @@ def get_mounted_devs():
     return res
 
 def flash(dev):
-    flash_cmd = ["/bin/dd", "if=/home/pi/Downloads/2019-07-10-raspbian-buster-lite.img", f"of={dev}"]
-    output = subprocess.check_output(flash_cmd).decode("utf-8")
-    print(output)
-    return True
-
-disp_string("GO")
-
-done = set()
-while True:
+    loader.q.put(dev)
     try:
+        flash_cmd = ["/bin/dd", "if=/home/pi/Downloads/2019-07-10-raspbian-buster-lite.img", f"of={dev}"]
+        output = subprocess.check_output(flash_cmd).decode("utf-8")
+        print(output)
+        return True
+    except BaseException as err:
+        print(err)
+        disp_string('ERR')
+    finally:
+        loader.q.get()
+
+if __name__=="__main__":
+
+    disp_string("GO")
+
+    done = set()
+    while True:
         devs = get_mounted_devs()
         done = done.intersection(devs)
         for dev in devs:
@@ -49,9 +61,7 @@ while True:
                 disp_string(dev.split("/")[2])
                 if flash(dev):
                     print(f"Flashed {dev}")
-                    disp_string("DONE")
+                    disp_string("GO")
                     time.sleep(.5)
                     done.add(dev)
         time.sleep(1)
-    except BaseException as err:
-        disp_string("err")