How do different common components communicate with each other in the same interface?

excuse me, how do different common components communicate with each other using the same interface?

clipboard.png

for example, in the above figure, there are two common components in the two red boxes. When I click the Save button, I need to get the modified value in another common component. [question 1] how to get this?
[question 2] do I trigger the bus.$emit event if I use bus, @ change?
[question 3] is there another way?
just joined the pit, lack of actual combat experience, but also asked the gods to give advice one or two, thank you ~

Mar.23,2021

bus method, bus's pit is filled, see https://codeshelper.com/q/10.

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