How to solve the UI memory leak?

[zhumingqi]

I used UIFlow2.3.3 to develop a simple UI demo. There is only one image widget to switch 2 JPG images every second. When I monitor the memory with gc.mem_free, I found the memory reduced continiously. And finally, the image switching was stop, but the loop was running. I wonder how to solve the UI memory leak? Here is my python code:
import os, sys, io
import M5
from M5 import *
import time

image0 = None
oldData14 = None

ImgFlag = None

def setup():
global image0, oldData14, ImgFlag

M5.begin()
Widgets.fillScreen(0x000000)
image0 = Widgets.Image("/flash/res/img/default.jpg", 0, 0, scale_x=1, scale_y=1)

image0.setImage("/flash/res/img/RotaryBGBacklight.jpg")
ImgFlag = 0

def loop():
global image0, oldData14, ImgFlag
M5.update()
if (time.localtime())[5] != oldData14:
PrintFreeMem()
oldData14 = (time.localtime())[5]
if ImgFlag == 0:
image0.setImage("/flash/res/img/RotaryBGBT.jpg")
ImgFlag = 1
elif ImgFlag == 1:
image0.setImage("/flash/res/img/RotaryBGBacklight.jpg")
ImgFlag = 0
else:
pass

def PrintFreeMem():
print("Free mem:", gc.mem_free())

if name == 'main':
try:
setup()
while True:
loop()
except (Exception, KeyboardInterrupt) as e:
try:
from utility import print_error_msg
print_error_msg(e)
except ImportError:
print("please update to latest firmware")

And my UIFlow2 design: