How do you add mapping of struct array in ink?

Question

How to create a mapping of a vector of struct, also how to assign value and get the value in this data structure. I didn't find the documentation on the official doc. Is there any downside to using such a data structure in the context of smart contract?

Answer 1

Instead of an array of structs, you can use a vector of structs to add on mapping. Here is an example:

list_of_proposal: Mapping<AccountId, Vec<Proposal>>

pub struct Proposal{
....
...
}

// Get list_of_proposal (vector of structs)

pub fn get_proposal(&self) -> Vec<Proposal> 
{  
let proposal =
self.list_of_proposals(&self.env.caller());  
proposal 
.... 
}

//For add a new proposal

pub fn set_proposal(&self)
{
let vec = Vec::new();
let new_proposal = Proposal
{
...
...
}
vec.push(new_proposal);
self.list_of_proposal.insert(&vec);
}