Variables and functions from injectedJavaScript not available on Android

Bug description: On Android, variables and functions declared in injectedJavaScript are not available in code run by injectJavaScript, whereas on iOS they are. Please note that I’m using source={{ html: ... }}, not loading an external URI. I believe the behaviour on iOS is correct, that on Android is not.

To Reproduce: I created a repo that demonstrates this issue. I was careful to create a descriptive git history, so I hope it is pretty self-explanatory: https://github.com/svdo/VarIssue. This repo contains a complete react native project that you should be able to run yourself (make sure Android emulator is running):

yarn
yarn react-native start --reset-cache
yarn react-native run-ios
yarn react-native run-android

Environment:

• OS: Android 9 and iOS 11
• react-native-webview version: 5.8.1
• react-native info:

  React Native Environment Info:
    System:
      OS: macOS 10.14.4
      CPU: (12) x64 Intel(R) Core(TM) i7-8850H CPU @ 2.60GHz
      Memory: 18.87 MB / 16.00 GB
      Shell: 5.3 - /bin/zsh
    Binaries:
      Node: 11.14.0 - /var/folders/0d/5_t6qk7s06qf94jnypzwh6yh0000gp/T/yarn--1557086445011-0.06815149805556375/node
      Yarn: 1.15.2 - /var/folders/0d/5_t6qk7s06qf94jnypzwh6yh0000gp/T/yarn--1557086445011-0.06815149805556375/yarn
      npm: 6.9.0 - ~/.homebrew/bin/npm
    SDKs:
      iOS SDK:
        Platforms: iOS 12.2, macOS 10.14, tvOS 12.2, watchOS 5.2
    IDEs:
      Xcode: 10.2.1/10E1001 - /usr/bin/xcodebuild
    npmPackages:
      react: 16.8.3 => 16.8.3
      react-native: 0.59.5 => 0.59.5
  

Note

• Using injectJavaScript to declare the variables and function, instead of injectedJavaScript, will cause everything to work as expected. This is demonstrated in commit https://github.com/svdo/VarIssue/commit/72f3fa0ed729a5c226a615144380f4c5a7a92997.
• This may or may not be related to issue #445.

[its-wufu]

I solved this by using the onLoad prop. I load the following function into onLoad:

  const injectJSFileFromWeb = () => {
    webViewRef.current.injectJavaScript(
      `var corescript = document.createElement('script');
        corescript.type = 'text/javascript';
        corescript.src = "https://url/to/code.js";
        var parent = document.getElementsByTagName('head').item(0);
        parent.appendChild(corescript);
        console.log('loaded...')`,
    );
  };

I red that you should care about the linebreaks.

Using this method I can access variables when calling the injectJavaScript method.

[ccfz]

This is still a problem on version: 9.1.4. I could not try 9.2.0 because of another known build error. Once the fix for 9.2.0 is released I try it as well. But for the moment the workaround that @svdo posted above worked for me!