Subsequent script injections do not stack

[peter-meemo]

Documentation seems to imply that injected javascript code can see/use previously injected code, but this does not seem to be the case. From the example:

await this.webViewController.injectScriptFile("https://code.jquery.com/jquery-3.3.1.min.js");
    this.webViewController.injectScriptCode("""
      \$( "body" ).html( "Next Step..." )
    """);

If I use this code and await the second injection, it gives ReferenceError: $ is not defined.

A similar test setup:

class miab extends InAppBrowser {
  @override
  Future<void> onLoadStop(String url) async {
    await this.webViewController.injectScriptCode(_withErrorHandler("function foo() {return 2;}"));
    final result = await this.webViewController.injectScriptCode(_withErrorHandler("foo();"));
  }

  @override
  void onBrowserCreated() {
    webViewController.addJavaScriptHandler('msg', ((List<dynamic> args) {
      print('MIAB got msg: $args');
    }));
  }

  static String _withErrorHandler(String js) =>
      "try {$js} catch(e) {window.flutter_inappbrowser.callHandler('msg', 'err', e.toString());}";
}

shows

MIAB got msg: [err, ReferenceError: foo is not defined]

I also see this error, which seems related to https://github.com/pichillilorenzo/flutter_inappbrowser/issues/104

E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): Failed to handle method call result
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): java.lang.NullPointerException: Attempt to read from field 'com.pichillilorenzo.flutter_inappbrowser.InAppWebView.InAppWebView com.pichillilorenzo.flutter_inappbrowser.FlutterWebView.webView' on a null object reference
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at com.pichillilorenzo.flutter_inappbrowser.JavaScriptBridgeInterface$1$1.success(JavaScriptBridgeInterface.java:55)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at io.flutter.plugin.common.MethodChannel$IncomingResultHandler.reply(MethodChannel.java:179)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at io.flutter.embedding.engine.dart.DartMessenger.handlePlatformMessageResponse(DartMessenger.java:103)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessageResponse(FlutterJNI.java:228)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at android.os.MessageQueue.nativePollOnce(Native Method)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at android.os.MessageQueue.next(MessageQueue.java:326)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at android.os.Looper.loop(Looper.java:160)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at android.app.ActivityThread.main(ActivityThread.java:6669)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at java.lang.reflect.Method.invoke(Native Method)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
E/MethodChannel#com.pichillilorenzo/flutter_inappbrowser(23351): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

[peter-meemo]

It seems like calls to injectScriptCode are wrapped such that it's not surprising that they don't interact in this way (thought it would be good to document this). injectScriptFile seems like it modifies the document, so I would expect it to work.

[peter-meemo]

It appears that this does work in ios, so this is probably a bug on the android side?

[peter-meemo]

Looks like this is due to a combination of problems in my test setup and various pages blocking scripts loaded via injectScriptFile.