导航后，我得到的是白页而不是路由器页面

Question

当我从一个屏幕导航到其他屏幕时，我在项目中使用了反应导航，我得到的是白色屏幕，而不是应该显示的屏幕。但是当我单击“后退”按钮时，我可以查看页面我想要的。

以下是我项目的package.json：

{

 "name": "jul20-BHI",
 "version": "0.1.0",
"private": true,
"devDependencies": {
"react-native-scripts": "1.14.0",
"jest-expo": "~27.0.0",
"react-test-renderer": "16.3.1"
},

 "main": "./node_modules/react-native-scripts/build/bin/crna-entry.js",
"scripts": {
 "start": "react-native-scripts start",
"eject": "react-native-scripts eject",
"android": "react-native-scripts android",
"ios": "react-native-scripts ios",
"test": "jest"
},

 "jest": {
 "preset": "jest-expo"
 },

    "dependencies": {
  "expo": "^27.0.1",
"react": "16.3.1",
"react-native": "~0.55.2",
"react-native-card-view": "0.0.3",
"react-native-elements": "^0.19.1",
"react-native-material-dropdown": "^0.11.1",
"react-native-material-textfield": "^0.12.0",
"react-native-simple-radio-button": "^2.7.2",
"react-native-table-component": "^1.1.8",
"react-navigation": "^2.8.0"

}     } 有人可以帮我解决这个问题吗？

预先感谢