[Closed] Real time refresh/upgrade rollout background when include dotnetcontrol object

Hi everyone,
I have a question about the refreshing rollout interface,my goal what I want is like below-The CLEAN rollout:

When another rollout created,the current rollout background color will be dirty,if you minimize it and maximize back,the background color will be totally lost ,how can I refresh the interface to avoid this issue?Thanks in advance!

Background color lost…

try(destroydialog test_background) catch()
rollout test_background "test"
(   
   dotnetcontrol lb_content "label" pos:[30,30]
   
   on test_background open do
   (
      lb_content.text="Keep background clean..."
      lb_content.bounds=dotNetObject "system.drawing.rectangle" 5 20 310 20
      lb_content.forecolor =lb_content.forecolor.fromARGB 0 0 0
      lb_content.location = dotNetObject "System.Drawing.Point" 0 0
      try(destroydialog test_go_01) catch()
      rollout test_go_01 "test2"
      (
         label a1 "" pos:[10,10]
      )
      CreateDialog test_go_01 100 25
   )
)
CreateDialog test_background 400 250 lockwidth:true lockheight:true style:#(#style_titlebar,#style_sysmenu,#style_minimizebox) bgcolor:(color 255 255 255)