unity-webview

unity-webview is a plugin for Unity 5 that overlays WebView components on Unity view. It works on Android, iOS, Unity Web Player, and Mac (Windows is not supported for now).

unity-webview is derived from keijiro-san's https://github.com/keijiro/unity-webview-integration .

NOTE: This plugin overlays native WebView/WKWebView views over unity's rendering view and doesn't support those views in 3D. gree#658 (comment) discusses other solutions.

Sample Project

It is placed under sample/. You can open it and import the plugin as below:

1. Open sample/Assets/Sample.unity.
2. Open dist/unity-webview.unitypackage and import all files. It might be easier to extract dist/unity-webview.zip instead if you've imported unity-webview before.

NOTE: The current implementation for Android utilizes Android Fragment for enabling the file input field after https://github.com/gree/unity-webview/commit/a1a2a89d2d0ced366faed9db308ccf4f689a7278 and may cause new issues that were not found before. If you don't need the file input field, you can install dist/unity-webview-nofragment.unitypackage or dist/unity-webview-nofragment.zip for selecting the variant without Fragment.

Package Manager

If you use Unity 2019.4 or later, the plugin can also be imported with Package Manager, by adding the following entry in your Packages/manifest.json:

{
  "dependencies": {
    ...
    "net.gree.unity-webview": "https://github.com/gree/unity-webview.git?path=/dist/package",
    ...
  }
}

or the following for selecting the variant without Fragment:

{
  "dependencies": {
    ...
    "net.gree.unity-webview": "https://github.com/gree/unity-webview.git?path=/dist/package-nofragment",
    ...
  }
}

NOTE: Importing with Package Manager currently doesn't work well for WebGL. Please check the instruction for dist/unity-webview.unitypackage.

Platform Specific Notes

Mac (Editor)

macOS Version

The current implementation utilizes https://developer.apple.com/documentation/webkit/wkwebview/2873260-takesnapshotwithconfiguration to capture an offscreen webview image so that macOS 10.13 (High Sierra) or later is required.

App Transport Security

Since Unity 5.3.0, Unity.app is built with ATS (App Transport Security) enabled and non-secured connection (HTTP) is not permitted. If you want to open http://foo/bar.html with this plugin on Unity Mac Editor, you need to open /Applications/Unity5.3.4p3/Unity.app/Contents/Info.plist with a text editor and add the following,

--- Info.plist~	2016-04-11 18:29:25.000000000 +0900
+++ Info.plist	2016-04-15 16:17:28.000000000 +0900
@@ -57,5 +57,10 @@
 	<string>EditorApplicationPrincipalClass</string>
 	<key>UnityBuildNumber</key>
 	<string>b902ad490cea</string>
+	<key>NSAppTransportSecurity</key>
+	<dict>
+		<key>NSAllowsArbitraryLoads</key>
+		<true/>
+	</dict>
 </dict>
 </plist>

or invoke the following from your terminal,

/usr/libexec/PlistBuddy -c "Add NSAppTransportSecurity:NSAllowsArbitraryLoads bool true" /Applications/Unity/Unity.app/Contents/Info.plist

References

• gree#64
• https://onevcat.zendesk.com/hc/en-us/articles/215527307-I-cannot-open-the-web-page-in-Unity-Editor-

Separeted Mode

A separate window will be shown if separated: true is specified:

        webViewObject = (new GameObject("WebViewObject")).AddComponent<WebViewObject>();
        webViewObject.Init(
            ...
#if UNITY_EDITOR
            separated: true
#endif
            ...);

This is based on gree#161 and allows a developer to utilize the Safari debugger.

iOS

enableWKWebView

The implementation now supports WKWebView but it is disabled by default. For enabling it, please set enableWKWebView as below:

        webViewObject = (new GameObject("WebViewObject")).AddComponent<WebViewObject>();
        webViewObject.Init(
            ...
            enableWKWebView: true);

(cf. https://github.com/gree/unity-webview/blob/de9a25c0ab0622b15c15ecbc0c7cd85858aa7745/sample/Assets/Scripts/SampleWebView.cs#L94)

This flag have no effect on platforms without WKWebView (such as iOS7 and Android) and should always be set true for iOS9 or later (see the next section).

WKWebView only implementation for iOS9 or later

Apple recently sends the following warning for an app submission,

ITMS-90809: Deprecated API Usage - Apple will stop accepting submissions of apps that use UIWebView APIs . See https://developer.apple.com/documentation/uikit/uiwebview for more information.

so the current implementation for iOS has two variations (Assets/Plugins/iOS/WebView.mm and Assets/Plugins/iOS/WebViewWithUIWebView.mm), in which new one (Assets/Plugins/iOS/WebView.mm) utilizes only WKWebView if iOS deployment target is iOS9 or later. Please modify #if __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_9_0 in those files if you need to change this behavior.

NOTE: WKWebView is available since iOS8 but was largely changed in iOS9, so we use ___IPHONE_9_0 instead of __IPHONE_8_0 NOTE: Several versions of Unity themselves also have the ITMS-90809 issue (cf. https://issuetracker.unity3d.com/issues/ios-apple-throws-deprecated-api-usage-warning-for-using-uiwebview-when-submitting-builds-to-the-app-store-connect )./

XMLHttpRequest for file URLs

WKWebView doesn't allow to access file URLs with XMLHttpRequest. This limitation can be relaxed by allowFileAccessFromFileURLs/allowUniversalAccessFromFileURLs settings. Those are however private APIs so currently disabled by default. For enabling them, please define UNITYWEBVIEW_IOS_ALLOW_FILE_URLS.

cf. gree#785 cf. gree#224 (comment)

Android

File Input Field

The current implementation for Android utilizes Android Fragment for enabling the file input field <input type="file"> since https://github.com/gree/unity-webview/commit/a1a2a89d2d0ced366faed9db308ccf4f689a7278 and may cause new issues that were not found before. If you don't need the file input field, you can install dist/unity-webview-nofragment.unitypackage or dist/unity-webview-nofragment.zip for selecting the variant without Fragment.

If you utilize the default one and want to enable the file input field, you also have to set one of the following permissions since gree#655 .

• android.permission.READ_EXTERNAL_STORAGE
• android.permission.WRITE_EXTERNAL_STORAGE
• android.permission.CAMERA

You can set android.permission.WRITE_EXTERNAL_STORAGE by setting Player Settings/Other Settings/Write Permission to External (SDCard). You can set android.permission.CAMERA by defining UNITYWEBVIEW_ANDROID_ENABLE_CAMERA (cf. Camera/Audio Permission/Feature).

hardwareAccelerated

The main activity should have android:hardwareAccelerated="true", otherwise a webview won't run smoothly. Depending on unity versions, we need to set it as below (basically this will be done by post-process build scripts).

Unity 2018.1 or newer

Based on the technique discussed in https://forum.unity.com/threads/android-hardwareaccelerated-is-forced-false-in-all-activities.532786/ and https://github.com/Over17/UnityAndroidManifestCallback, Assets/Plugins/Editor/UnityWebViewPostprocessBuild.cs edit the manifest to set android:hardwareAccelerated="true". Please note this works with the gradle (not internal) build setting.

Unity 2017.x - 2018.0

Unity forcibly set android:hardwareAccelerated="false" regardless of its setting in Plugins/Android/AndroidManifest.xml, as discussed in gree#382 (see also gree#342 and https://forum.unity.com/threads/android-hardwareaccelerated-is-forced-false-in-all-activities.532786/ ), and there is no solution for automatically correcting this setting. Please export the project and manually correct AndroidManifest.xml.

Unity 5.x or older

After the initial build, Assets/Plugins/Editor/UnityWebViewPostprocessBuild.cs will copy Temp/StatingArea/AndroidManifest-main.xml to Assets/Plugins/Android/AndroidManifest.xml, edit the latter to add android:hardwareAccelerated="true" to <activity android:name="com.unity3d.player.UnityPlayerActivity" .... Then you need to build the app again to reflect this change.

NOTE: Unity 5.6.1p4 or newer (including 2017 1.0) seems to fix the following issue (cf. gree#212 (comment))

For Unity 5.6.0 and 5.6.1 (except 5.6.1p4), you also need to modify android:name from com.unity3d.player.UnityPlayerActivity to net.gree.unitywebview.CUnityPlayerActivity. This custom activity implementation will adjust Unity's SurfaceView z order. Please refer plugins/Android/src/net/gree/unitywebview/CUnityPlayerActivity.java and plugins/Android/src/net/gree/unitywebview/CUnityPlayer.java if you already have your own activity implementation.

usesCleartextTraffic

For allowing http cleartext traffic for Android API level 28 or higher, please define UNITYWEBVIEW_ANDROID_USES_CLEARTEXT_TRAFFIC so that Assets/Plugins/Editor/UnityWebViewPostprocessBuild.cs adds android:usesCleartextTraffic="true" to the applicaiton.

Camera/Audio Permission/Feature

For allowing camera access (navigator.mediaDevices.getUserMedia({ video:true })), please define UNITYWEBVIEW_ANDROID_ENABLE_CAMERA so that Assets/Plugins/Editor/UnityWebViewPostprocessBuild.cs adds the followings to AndroidManifest.xml,

  <uses-permission android:name="android.permission.CAMERA" />
  <uses-feature android:name="android.hardware.camera" />

and call the following on runtime.

        webViewObject.SetCameraAccess(true);

For allowing microphone access (navigator.mediaDevices.getUserMedia({ audio:true })), please define UNITYWEBVIEW_ANDROID_ENABLE_MICROPHONE so that Assets/Plugins/Editor/UnityWebViewPostprocessBuild.cs adds the followings to AndroidManifest.xml,

  <uses-permission android:name="android.permission.MICROPHONE" />
  <uses-feature android:name="android.hardware.microphone" />
  <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
  <uses-permission android:name="android.permission.RECORD_AUDIO" />

and call the following on runtime.

        webViewObject.SetMicrophoneAccess(true);

Details for each Unity version are the same as for hardwareAccelerated. Please also note that it is necessary to request permissions at runtime for Android API 23 or later as below:

diff --git a/sample/Assets/Scripts/SampleWebView.cs b/sample/Assets/Scripts/SampleWebView.cs
index a62c1ca..a5efe9f 100644
--- a/sample/Assets/Scripts/SampleWebView.cs
+++ b/sample/Assets/Scripts/SampleWebView.cs
@@ -24,6 +24,9 @@ using UnityEngine;
 using UnityEngine.UI;
 using UnityEngine.Networking;
 #endif
+#if !UNITY_EDITOR && UNITY_ANDROID
+using UnityEngine.Android;
+#endif
 
 public class SampleWebView : MonoBehaviour
 {
@@ -31,8 +34,29 @@ public class SampleWebView : MonoBehaviour
     public GUIText status;
     WebViewObject webViewObject;
 
+#if !UNITY_EDITOR && UNITY_ANDROID
+    bool inRequestingCameraPermission;
+
+    void OnApplicationFocus(bool hasFocus)
+    {
+        if (inRequestingCameraPermission && hasFocus) {
+            inRequestingCameraPermission = false;
+        }
+    }
+#endif
+
     IEnumerator Start()
     {
+#if !UNITY_EDITOR && UNITY_ANDROID
+        if (!Permission.HasUserAuthorizedPermission(Permission.Camera))
+        {
+            inRequestingCameraPermission = true;
+            Permission.RequestUserPermission(Permission.Camera);
+        }        
+        while (inRequestingCameraPermission) {
+            yield return new WaitForSeconds(0.5f);
+        }
+#endif
         webViewObject = (new GameObject("WebViewObject")).AddComponent<WebViewObject>();
         webViewObject.Init(
             cb: (msg) =>

(cf. gree#473 (comment)) (cf. https://docs.unity3d.com/Manual/android-RequestingPermissions.html)

How to build WebViewPlugin.jar

The following steps are for Mac but you can follow similar ones for Windows.

1. Place Unity 5.6.1f1 as /Applications/Unity5.6.1f1 on osx or \Program Files\Unity5.6.1f1\ on windows.
2. Install Android Studio.
3. Open Android Studio and select "Configure/SDK Manager", select the followings with "Show Package Details", and click OK.

• SDK Platforms
  • Android 6.0 (Marshmallow)
    • Android SDK Platform 23
• SDK Tools
  • Android SDK Build Tools
    • 28.0.2

4. Open Terminal.app and perform the followings. You should find unity-webview/build/Packager/Assets/Plugins/Android/WebViewPlugin.jar if successful.

$ export ANDROID_HOME=~/Library/Android/sdk
$ export PATH=$PATH:~/Library/Android/sdk/platform-tools/bin:~/Library/Android/sdk/tools:~/Library/Android/sdk/tools/bin
$ cd unity-webview/plugins/Android
$ ./install.sh

WebGL

NOTE: for Unity 2020.1.0f1 or newer, please use unity-webview-2020 instead of unity-webview below.

After importing dist/unity-webview.unitypackage or dist/unity-webview.zip, please copy WebGLTemplates/Default/TemplateData from your Unity installation to Assets/WebGLTemplates/unity-webivew. If you utilize Unity 2018.4.13f1 for example,

$ cp -a /Applications/Unity/Hub/Editor/2018.4.13f1/PlaybackEngines/WebGLSupport/BuildTools/WebGLTemplates/Default/TemplateData Assets/WebGLTemplates/unity-webview

Then in Project Settings/Player/Resolution and Presentation, please select unity-webview in WebGL Template.

Web Player

NOTE: Web Player is obsolete so that the support for it will be removed.

The implementation utilizes IFRAME so please put both "an_unityplayer_page.html" and "a_page_loaded_in_webview.html" should be placed on the same domain for avoiding cross-domain requests.