Question

我有以下代码：

import React, { Component } from 'react';
import {Button} from "@material-ui/core";
import Selector from "./Selector"

class Trigger extends Component {

  constructor(props) {
    super(props);
    this.state = {
      clicks: 0
    };
  }

  IncrementItem = () => {
    this.setState({
      clicks: this.state.clicks + 1
    });
  }

  DecreaseItem = () => {
    this.setState({
      clicks: this.state.clicks - 1
    });
  }

  render() {
    console.log(this.state)
    return (
      <div>

        <Button
        onClick={this.IncrementItem}
        variant="contained"
        color='primary'>
        add
        </Button>

        {this.state.clicks ?
          <Button
          onClick={this.DecreaseItem}
          variant="contained"
          color='primary'>
          remove
          </Button>:
          null}

        {this.state.clicks ?
          <Selector>
          </Selector>:
          null}

      </div>
    );
  }
}

export default Trigger;

想法：

1. The first button increases this.state.clicks
2. The second button is shown only if this.state.clicks > 0
3. The second button decreases this.state.clicks

问题：渲染选择器组件n次（不仅像我的代码中那样一次），其中n = this.state.clicks。

注意：选择器组件由2个选择器和多个选项组成，因此它不是字符串数组。非常感谢！

Answer 1

尝试一下：

public interface Object1Repository extends JpaRepository<Object1, Long> { public List<Object2> findById(Long id);
 }

渲染反应组件n次

1 个答案: