在官方 material-ui 文档中，此处AppBar组件的示例如下所示：

import React, {Component} from 'react';
import AppBar from 'material-ui/AppBar';
import IconButton from 'material-ui/IconButton';
import IconMenu from 'material-ui/IconMenu';
import MenuItem from 'material-ui/MenuItem';
import FlatButton from 'material-ui/FlatButton';
import Toggle from 'material-ui/Toggle';
import MoreVertIcon from 'material-ui/svg-icons/navigation/more-vert';
import NavigationClose from 'material-ui/svg-icons/navigation/close';

class Login extends Component {
  static muiName = 'FlatButton';

  render() {
    return (
      <FlatButton {...this.props} label="Login" />
    );
  }
}

const Logged = (props) => (
  <IconMenu
    {...props}
    iconButtonElement={
      <IconButton><MoreVertIcon /></IconButton>
    }
    targetOrigin={{horizontal: 'right', vertical: 'top'}}
    anchorOrigin={{horizontal: 'right', vertical: 'top'}}
  >
    <MenuItem primaryText="Refresh" />
    <MenuItem primaryText="Help" />
    <MenuItem primaryText="Sign out" />
  </IconMenu>
);

Logged.muiName = 'IconMenu';

/**
 * This example is taking advantage of the composability of the `AppBar`
 * to render different components depending on the application state.
 */
class AppBarExampleComposition extends Component {
  state = {
    logged: true,
  };

  handleChange = (event, logged) => {
    this.setState({logged: logged});
  };

  render() {
    return (
      <div>
        <Toggle
          label="Logged"
          defaultToggled={true}
          onToggle={this.handleChange}
          labelPosition="right"
          style={{margin: 20}}
        />
        <AppBar
          title="Title"
          iconElementLeft={<IconButton><NavigationClose /></IconButton>}
          iconElementRight={this.state.logged ? <Logged /> : <Login />}
        />
      </div>
    );
  }
}

export default AppBarExampleComposition;

我的问题是关于陈述的

static muiName = 'FlatButton';

和

Logged.muiName = 'IconMenu';

什么是muiName以及何时/为什么我必须设置它？是否应该始终设置为render()方法中顶级组件的名称？

在同一个网页上，有未设置AppBarwhere 的示例muiName。