Javascript 类型错误：无法读取未定义的属性“prepareStyles”

TypeError: Cannot read property 'prepareStyles' of undefined

提问by daydreamer

My Componentlooks like

我的Component样子

import React, {PropTypes} from 'react';
import TransactionListRow from './TransactionListRow';
import {Table, TableBody, TableHeader, TableHeaderColumn, TableRow} from 'material-ui/Table';

const TransactionList = ({transactions}) => {
  return (
    <Table>
      <TableHeader displaySelectAll={false}>
        <TableRow>
          <TableHeaderColumn>Name</TableHeaderColumn>
          <TableHeaderColumn>Amount</TableHeaderColumn>
          <TableHeaderColumn>Transaction</TableHeaderColumn>
          <TableHeaderColumn>Category</TableHeaderColumn>
        </TableRow>
      </TableHeader>
      <TableBody>
        {transactions.map(transaction =>
          <TransactionListRow key={transaction.id} transaction={transaction}/>
        )}
      </TableBody>
    </Table>
  );
};

TransactionList.propTypes = {
  transactions: PropTypes.array.isRequired
};

export default TransactionList;

The test is

测试是

import {mount} from 'enzyme';
import TransactionList from './TransactionList';
import {TableHeaderColumn} from 'material-ui/Table';
import getMuiTheme from 'material-ui/styles/getMuiTheme';

describe("<TransactionList />", ()=> {
  it('renders four <TableHeaderColumn /> components', () => {
    const wrapper = mount(<TransactionList transactions={[]}/>);
    expect(wrapper.find(TableHeaderColumn)).to.have.length(4);
  });
});

My dependencies are

我的依赖是

 "dependencies": {
    "babel-polyfill": "6.8.0",
    "bootstrap": "3.3.6",
    "jquery": "2.2.3",
    "react": "15.3.2",
    "react-dom": "15.3.2",
    "react-redux": "4.4.5",
    "react-router": "2.8.1",
    "react-router-redux": "4.0.6",
    "redux": "3.6.0",
    "redux-thunk": "2.1.0",
    "toastr": "2.1.2",
    "react-tap-event-plugin": "^1.0.0",
    "material-ui": "0.15.4"
  }

When I run test I see

当我运行测试时，我看到

 1) <TransactionList /> renders four <TableHeaderColumn /> components:
     TypeError: Cannot read property 'prepareStyles' of undefined
      at Table.render (node_modules/material-ui/Table/Table.js:155:48)
      at node_modules/react/lib/ReactCompositeComponent.js:793:21
      at measureLifeCyclePerf (node_modules/react/lib/ReactCompositeComponent.js:74:12)
      at ReactCompositeComponentMixin._renderValidatedComponentWithoutOwnerOrContext (node_modules/react/lib/ReactCompositeComponent.js:792:27)
      at ReactCompositeComponentMixin._renderValidatedComponent (node_modules/react/lib/ReactCompositeComponent.js:819:34)
      at ReactCompositeComponentMixin.performInitialMount (node_modules/react/lib/ReactCompositeComponent.js:361:30)
      at ReactCompositeComponentMixin.mountComponent (node_modules/react/lib/ReactCompositeComponent.js:257:21)
      at Object.ReactReconciler.mountComponent (node_modules/react/lib/ReactReconciler.js:47:35)
      at ReactCompositeComponentMixin.performInitialMount (node_modules/react/lib/ReactCompositeComponent.js:370:34)
      at ReactCompositeComponentMixin.mountComponent (node_modules/react/lib/ReactCompositeComponent.js:257:21)
      at Object.ReactReconciler.mountComponent (node_modules/react/lib/ReactReconciler.js:47:35)
      at ReactCompositeComponentMixin.performInitialMount (node_modules/react/lib/ReactCompositeComponent.js:370:34)
      at ReactCompositeComponentMixin.mountComponent (node_modules/react/lib/ReactCompositeComponent.js:257:21)
      at Object.ReactReconciler.mountComponent (node_modules/react/lib/ReactReconciler.js:47:35)
      at ReactCompositeComponentMixin.performInitialMount (node_modules/react/lib/ReactCompositeComponent.js:370:34)
      at ReactCompositeComponentMixin.mountComponent (node_modules/react/lib/ReactCompositeComponent.js:257:21)
      at Object.ReactReconciler.mountComponent (node_modules/react/lib/ReactReconciler.js:47:35)
      at mountComponentIntoNode (node_modules/react/lib/ReactMount.js:105:32)
      at ReactReconcileTransaction.Mixin.perform (node_modules/react/lib/Transaction.js:138:20)
      at batchedMountComponentIntoNode (node_modules/react/lib/ReactMount.js:127:15)
      at ReactDefaultBatchingStrategyTransaction.Mixin.perform (node_modules/react/lib/Transaction.js:138:20)
      at Object.ReactDefaultBatchingStrategy.batchedUpdates (node_modules/react/lib/ReactDefaultBatchingStrategy.js:63:19)
      at Object.batchedUpdates (node_modules/react/lib/ReactUpdates.js:98:20)
      at Object.ReactMount._renderNewRootComponent (node_modules/react/lib/ReactMount.js:321:18)
      at Object.ReactMount._renderSubtreeIntoContainer (node_modules/react/lib/ReactMount.js:402:32)
      at Object.ReactMount.render (node_modules/react/lib/ReactMount.js:423:23)
      at Object.ReactTestUtils.renderIntoDocument (node_modules/react/lib/ReactTestUtils.js:84:21)
      at renderWithOptions (node_modules/enzyme/build/react-compat.js:175:26)
      at new ReactWrapper (node_modules/enzyme/build/ReactWrapper.js:87:59)
      at mount (node_modules/enzyme/build/mount.js:21:10)
      at Context.<anonymous> (TransactionList.test.js:7:1)

Please help me understand what is going wrong and how should I fix this? I am new to Reactand its ecosystem

请帮助我了解出了什么问题，我应该如何解决这个问题？我是新来的React，它的生态系统

回答by albrnick

You need to wrap your table in a MuiThemeProvider tag

您需要将您的表格包装在 MuiThemeProvider 标签中

like:

喜欢：

import MuiThemeProvider from 'material-ui/styles/MuiThemeProvider'

const TransactionList = ({transactions}) => {
  return (
    <MuiThemeProvider>
      <Table>
...
      </Table>
    </MuiThemeProvider>
  );
};

回答by Narita

If we follow the instructions in the order presented in the Material UI wesite, we can find the solution right there i.e. in the Usage section. They have declared the pre requisite of defining the theme as a Provider, prior to any component usage. These themes can also be customized.

如果我们按照 Material UI wesite 中显示的顺序进行操作，我们可以在那里找到解决方案，即在使用部分。他们已经声明了在使用任何组件之前将主题定义为Provider的先决条件。这些主题也可以自定义。

http://www.material-ui.com/#/get-started/usage

http://www.material-ui.com/#/get-started/usage

Clearly stated with snippet -

用片段清楚地说明 -

import React from 'react';
import ReactDOM from 'react-dom';
import MuiThemeProvider from 'material-ui/styles/MuiThemeProvider';
import MyAwesomeReactComponent from './MyAwesomeReactComponent';

const App = () => (
  <MuiThemeProvider>
    <MyAwesomeReactComponent />
  </MuiThemeProvider>
);

ReactDOM.render(
  <App />,
  document.getElementById('app')
);