通过React中的上下文向下传递画布引用

const CanvasContext = React.createContext();

class ParentComponent extends React.Component {
  constructor(props) {
    super(props);
    this.canvasRef = React.createRef();
  }

  render() {
    return (
      <CanvasContext.Provider value={this.canvasRef}>
        {/* 子组件 */}
      </CanvasContext.Provider>
    );
  }
}

class ChildComponent extends React.Component {
  render() {
    return (
      <CanvasContext.Consumer>
        {canvasRef => (
          // 使用画布引用进行操作
        )}
      </CanvasContext.Consumer>
    );
  }
}