I have tried the same requirement in my sample application. For your reference, I will share sample screenshots. I hope it will help you.
Domain model :
Step 1: I have added the OnChange event microflows in Acte input reference selector field.
Step 2: Instead of creating a new Acte object, update the input parameter TotalPrice value with the calculated SumofPrice value and set Refresh client to Yes. It will update the changes in the Client side dataview.
Thanks and regards,
No idear why you contacted me through mail but it seems that from the above comments you should be able to pinpoint your mistake. Did you set a breakpoint on your microflow and did you debug the values? You create a new object that you pass but did you fill it with the sum value? And why do you create a new object? How is this microflow triggered? From a page? Then why not pass the object on the page?
Edit your post with this info and may be we can then help you further.
Did you Commit and use Refresh in client?
thanks to all of you, now it's working fine