问从另一个类方法调用React setState不会更新set

EN

class Order extends React.Component {
  renderOrder = (key) => {
    const item = this.props.items[key];
    const count = this.props.order[key];
    return (
      <li key={key}>
        {count} pieces of {item.name}
        <button onClick={() => this.props.deductOrderCount(key)}>&minus;</button>
        <button onClick={() => this.props.removeFromOrder(key)}>&times;</button>
      </li>
    )
  }
  render() {
    const orderIds = Object.keys(this.props.order);
    return (
      <div>
        {orderIds.map(this.renderOrder)}
      </div>
    );
  }
}

class App extends React.Component {
  state = {
    items: { item1: { name: 'chocolate', price: 100}, item2: { name: 'bread', price: 50}},
    order: { item1: 3, item2: 2 }
  };

  removeFromOrder = key => {
    console.log('removing from order ' + key);
    // 1. take a copy of state
    const order = { ...this.state.order };
    // 2. remove item from order
    delete order[key];
    console.log(order)
    // 3. call setState to update our state object
    this.setState({ order });
  };

  deductOrderCount = (key) => {
    // 1. take a copy of state
    const order = { ...this.state.order };
    // 2. deduct 1 from the count and when it hits 0 remove from the order
    order[key] = (order[key] > 1) ? (order[key] - 1) : 0;
    if (order[key] === 0) this.removeFromOrder(key) //delete order[key]
    // 3. call setState to update our state object
    this.setState({ order })
  }

  render() {
    return (
      <div>
        <Order
          order={this.state.order}
          items={this.state.items} 
          removeFromOrder={this.removeFromOrder}  
          deductOrderCount={this.deductOrderCount}
        />
      </div>
    );
  }
}

ReactDOM.render(<App />, document.getElementById("main"));