How to save all values ​​in 1 state when clicking?

Question

React

I caught a blunt, let's say there is a state = {listItems: null} and when I click, I take some object and throw it there, on the next click I have to take the previous object + the new one and write it to the same state. At the end, the listItem should come out of the new objects, but how to do it. Here is my wrong implementation:

state = {
    listItems: null,
  }
addItem = (itemId) => {
    const newItem = this.props.itemsList.filter(
      item => itemId === item.id
    )
    this.setState(state => ({
       listItems: [state.listItems, newItem[0]]
    }))
  }

Answer 1

state = {
    listItems: [],
}

Answer 2

state = {
    listItems: []
  }
addItem = (itemId) => {
    const newItem = this.props.itemsList.find(item => itemId === item.id);
    
    newItem && this.setState(state => ({
       ...state,
       listItems: [...state.listItems, newItem]
    }))
  }