if I got your question right, you can retriev a list in a microflow and than aggregate the list. In the aggrigate activity you will find the function Sum,then you can select the attribute you want to sum and the result is a variable equal to the sum of the values. If that doesnt help, maybe you can specify a little more your question.
If I understand the question good; you can use a mf which retrieves the list items, and then the SUM of the list is what you need. Let me know if its not clear
You could also create a help object and store your summarisied values there
OK I got the microflow with the correct variable, but how can I show it on the right text box outside the mf?
for understanding just the following image:
I have the list of decimal values (Brutto) and in the textbox there should be the sum of these values
how can I display this variable in a text box?
It works fine but when I click a different row in my list view, the microflow should be triggered again. (The old value is still displayed)
Sorry. Maybe its easier to understand with pictures:
1.) I click on the first row => click on calculate sum => the sum will be displayed correctly
2.) when i click the second row the sum value changes without clicking the calculate button