Restoring app from background, results in webview_flutter showing a black screen.

[ElixirMike]

Steps to reproduce

Here is my current flutter versions

Flutter 3.10.6 • channel stable • https://github.com/flutter/flutter.git
Framework • revision f468f33 (10 months ago) • 2023-07-12 15:19:05 -0700
Engine • revision cdbeda788a
Tools • Dart 3.0.6 • DevTools 2.23.1

I am using webview_flutter version 4.5.0.

On my flutter app, when I'm viewing content on android device, using the webview_controller. If there is a link, I use a URL launcher package to launch external browser. Then, when I navigate to bring my app up from background, it shows black screen where HTML content should be.

I have not tested on IOS device.

Expected results

Expected that when I bring up app from background, it will show app with html content.

Actual results

When I bring app from background, it's showing black screen.

FYI, I can't reproduce this in my emulator...only happens on physical Pixel device.

Code sample

import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:webview_flutter_android/webview_flutter_android.dart';
import 'package:webview_flutter_wkwebview/webview_flutter_wkwebview.dart';

class MyWebView extends StatefulWidget {
final String htmlContent;

MyWebView({required this.htmlContent});

@OverRide
_MyWebViewState createState() => _MyWebViewState();
}

class _MyWebViewState extends State {
late final WebViewController _webViewController;
bool _isLoading = true;

Future _launchInBrowser(String url) async {
Uri uri = Uri.parse(url);

if (!await launchUrl(uri, mode: LaunchMode.externalApplication)) {
  throw Exception('Could not launch $url');
}

}

@OverRide
void initState() {
super.initState();
_webViewController = WebViewController();
_webViewController.setNavigationDelegate(NavigationDelegate(
onNavigationRequest: (NavigationRequest request) {
// Check if the URL is an external link and not the initial content load
if (request.url != 'about:blank' &&
Uri.tryParse(request.url)?.hasAbsolutePath == true) {
_launchInBrowser(request.url);
return NavigationDecision
.prevent; // Prevent further navigation in WebView
}
return NavigationDecision.navigate; // Allow navigation within WebView
// _launchInBrowser(request.url);
// return NavigationDecision.prevent;
},
onUrlChange: (UrlChange change) {
debugPrint('url change to ${change.url}');
},
));
loadHtml();
}

Future loadHtml() async {
//
//<style>html,body{font-size: 30px;}</style>
String htmlString =
'${widget.htmlContent}';
await _webViewController.loadHtmlString(htmlString);

setState(() {
  _isLoading = false;
});

}

@OverRide
Widget build(BuildContext context) {
return _isLoading
? Center(
child: CircularProgressIndicator(),
)
: Container(
height: 1600, child: WebViewWidget(controller: _webViewController));
}
}

Screenshots or Video

Screenshots / Video demonstration

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Logs

Logs

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Flutter Doctor output

[√] Flutter (Channel stable, 3.10.6, on Microsoft Windows [Version 10.0.19045.4291], locale en-US)
• Flutter version 3.10.6 on channel stable at C:\development\flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision f468f33 (10 months ago), 2023-07-12 15:19:05 -0700
• Engine revision cdbeda788a
• Dart version 3.0.6
• DevTools version 2.23.1

[√] Windows Version (Installed version of Windows is version 10 or higher)

[√] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
• Android SDK at C:\Users\Mike\AppData\Local\Android\Sdk
• Platform android-33, build-tools 30.0.3
• ANDROID_HOME = C:\Users\Mike\AppData\Local\Android\Sdk
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)
• All Android licenses accepted.

[!] Visual Studio - develop for Windows (Visual Studio Build Tools 2017 15.9.16)
• Visual Studio at C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools
• Visual Studio Build Tools 2017 version 15.9.28307.858
• Windows 10 SDK version 10.0.17763.0
X Visual Studio 2019 or later is required.
Download at https://visualstudio.microsoft.com/downloads/.
Please install the "Desktop development with C++" workload, including all of its default components

[√] Android Studio (version 4.1)
• Android Studio at C:\Program Files\Android\Android Studio
• Flutter plugin can be installed from:
https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)

[√] VS Code (version 1.89.0)
• VS Code at C:\Users\Mike\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.88.0

[√] Connected device (1 available)
• Windows (desktop) • windows • windows-x64 • Microsoft Windows [Version 10.0.19045.4291]

[√] Network resources
• All expected network resources are available.

[darshankawar]

only happens on physical Pixel device.

What OS version is on this device @ElixirMike ? If 14 or 15, most probably you are hitting #146499 that has been recently fixed. So you will need to switch to latest master or beta and re-run your scenario to check and confirm.

[ElixirMike]

I am on version14 on my phone. So you are saying I need to be on latest version of Flutter and version 4.7.0 of webview_flutter?

[Pholluxion]

same issue in Android 11 and version 4.7.0 of webview_flutter.

[ElixirMike]

Upgrading to the latest flutter and version .4.7.;0 of webview_flutter seems have solved the issue for me.