fixed log display bug

raspberry-pi/logHandler.py

@@ -4,9 +4,11 @@ class LogList():
   def __init__(self):
     self.log_list = list()
     self.read_index = 0
+    self.write_index = 0
 
   def add_item(self, item):
     self.log_list.append(item)
+    self.write_index += 1
     if len(self.log_list) > 100:
       self.log_list.pop(0)
 
@@ -22,7 +24,7 @@ class LogList():
 
   def get_new_items(self):
     items = self.log_list[self.read_index:]
-    self.read_index = len(self.log_list)
+    self.read_index = self.write_index
     return items