Web视图未显示React Native中的内容

Question

const WebViewExample = () =>(
  <View style = {{height : 350, width : '100%'}}>
       <WebView
         source = {{uri : 'https://www.google.com'}}
         injectJavaScript = {console.log('Injected')}
         scalesPageToFit = {true}
         style = {{backgroundColor : 'gray', marginTop : 20}}
         renderError = {(err)=> console.log(err)}
         startInLoadingState = {true}
         javaScriptEnabled = {true}
         domStorageEnabled = {true}
      /> 
   </View> 
)

我在App容器中渲染了这个组件。但是webview没有显示内容。