navigationOptions 配置隐藏标题栏和实现标题居中

import { Platform } from "react-native";
const TITLE_OFFSET = Platform.OS === 'ios' ? 70 : 56;

......

...隐藏标题栏
Home: { 
  screen: Example ,  
  navigationOptions: {
    header: null
  }
},
...标题栏的居中显示
Test: { 
  screen: Example, 
  navigationOptions: {
    title: 'test',
    headerTitleStyle:{
      textAlign: 'center',
      flex:1,
    },
    headerTitleContainerStyle:{
      left: TITLE_OFFSET,
      right: TITLE_OFFSET,
    }
  }
}

参考https://www.jianshu.com/p/a9a0c64a3b94