问React setState不更新精简数组

EN

    ... imports
    interface JoinedListState {
        availableItems: ListItem[]
        selectedItems: ListItem[]
    }

    export class JoinedList extends React.Component<JoinedListState, any>{
    // Create new arrays of the proper available and selected then set the new 
    // state
        private addItems(newItems: ListItem[]) {
            let oldSelected =  this.props.selectedItems;
            oldSelected.push.apply(oldSelected, newItems);
            let newSelected = oldSelected.sort((a, b) => {
                let nameA = a.value.toUpperCase();
                let nameB = b.value.toUpperCase();
                if (nameA < nameB) {
                    return -1
                }
                return 1
            });
            let newAvailable = this.props.availableItems
                .slice(0) // updated on recommendation of Sasha Kos
                .filter((item) => {
                    return newItems.findIndex(i => i.id == item.id) == -1
                });
            this.setState({
                availableItems: newAvailable,
                selectedItems: newSelected
            });
        }
        // Create new arrays of the proper available and selected then set the 
        //new state
        private removeItems(removedItems: ListItem[]) {
             .. same approach as addItems
            let newSelected = this.props.selectedItems.filter((item) => {
            // return only the items whose id does not exist on the newly 
            //removed items list
                return removedItems.findIndex(i => i.id == item.id) == -1
            })
            this.setState({
                availableItems: newAvailable,
                selectedItems: newSelected
            })
        }

        // Get the selected items by querying the DOM and send them to function 
        // to update state
         addSelected(event: React.FormEvent<HTMLButtonElement>) {
                // Code removed for brevity:  uses the event object to find the 
                //selected objects and builds a ListItem array called 'selected' 
                //to pass to addItems
                this.addItems(selected)
            }  

            removeSelected(event: React.FormEvent<HTMLButtonElement>) {
                // Code removed for brevity:  uses the event object to find the 
                //selected objects and builds a ListItem array called 'selected' 
                //to pass to addItems
                this.removeItems(selected)
            }

        render() {
            let aItems = this.renderOptionList(this.props.availableItems),
                sItems = this.renderOptionList(this.props.selectedItems);
            return (
                <div className='joined-list-container'>
                    <select key='available_list' className='available-list form- 
   control' multiple>
                        {aItems}
                    </select>
                    <span className='button-container'>
                        <button key='button1' className='btn btn-success' 
    onClick={this.addSelected.bind(this)}>
                            <span className='glyphicon glyphicon-chevron-right'> 
   </span>
                        </button>
                        <button key='button2' className='btn btn-danger' 
    onClick={this.removeSelected.bind(this)}>
                            <span className='glyphicon glyphicon-chevron-left'> 
   </span>
                        </button>
                    </span>
                    <select key='selected_list' className='selected-list form- 
   control' multiple>
                        {sItems}
                    </select>
               </div>
            )
        }

        renderOptionList(items: ListItem[]) {
            return items.map((item, idx) => {
                let key = `${item.value}_${idx}`
                return (
                    <option value={item.id} key={key}>{item.value}</option>
                )
            })
        }
     }

    this.setState({
        availableItems: [],
        selectedItems: newSelected
    })