Check WebView support and version

app/src/main/java/org/jellyfin/mobile/MainActivity.kt

@@ -7,6 +7,7 @@ import android.content.ServiceConnection
 import android.os.Bundle
 import android.os.IBinder
 import android.view.OrientationEventListener
+import androidx.appcompat.app.AlertDialog
 import androidx.appcompat.app.AppCompatActivity
 import androidx.lifecycle.lifecycleScope
 import kotlinx.coroutines.flow.collect
@@ -19,6 +20,7 @@ import org.jellyfin.mobile.player.PlayerFragment
 import org.jellyfin.mobile.utils.Constants
 import org.jellyfin.mobile.utils.PermissionRequestHelper
 import org.jellyfin.mobile.utils.SmartOrientationListener
+import org.jellyfin.mobile.utils.isWebViewSupported
 import org.jellyfin.mobile.utils.replaceFragment
 import org.jellyfin.mobile.viewmodel.MainViewModel
 import org.jellyfin.mobile.viewmodel.ServerState
@@ -53,6 +55,19 @@ class MainActivity : AppCompatActivity() {
         // Bind player service
         bindService(Intent(this, RemotePlayerService::class.java), serviceConnection, Service.BIND_AUTO_CREATE)
 
+        // Check WebView support
+        if (!isWebViewSupported()) {
+            AlertDialog.Builder(this).apply {
+                setTitle(R.string.dialog_web_view_not_supported)
+                setMessage(R.string.dialog_web_view_not_supported_message)
+                setCancelable(false)
+                setNegativeButton(R.string.dialog_button_close_app) { _, _ ->
+                    finish()
+                }
+            }.show()
+            return
+        }
+
         // Load UI
         lifecycleScope.launch {
             mainViewModel.serverState.collect { state ->

app/src/main/java/org/jellyfin/mobile/fragment/WebViewFragment.kt

@@ -1,6 +1,5 @@
 package org.jellyfin.mobile.fragment
 
-import android.annotation.SuppressLint
 import android.content.Intent
 import android.graphics.Rect
 import android.net.Uri
@@ -14,6 +13,7 @@ import android.webkit.WebResourceRequest
 import android.webkit.WebResourceResponse
 import android.webkit.WebView
 import androidx.activity.addCallback
+import androidx.appcompat.app.AlertDialog
 import androidx.core.view.ViewCompat
 import androidx.core.view.doOnNextLayout
 import androidx.fragment.app.Fragment
@@ -22,6 +22,7 @@ import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.lifecycleScope
 import androidx.webkit.WebResourceErrorCompat
 import androidx.webkit.WebViewClientCompat
+import androidx.webkit.WebViewCompat
 import androidx.webkit.WebViewFeature
 import kotlinx.coroutines.launch
 import org.jellyfin.apiclient.interaction.ApiClient
@@ -126,8 +127,41 @@ class WebViewFragment : Fragment(), NativePlayerHost {
         _webViewBinding = null
     }
 
-    @SuppressLint("SetJavaScriptEnabled")
     private fun WebView.initialize() {
+        if (isOutdated()) { // Check WebView version
+            AlertDialog.Builder(requireContext()).apply {
+                setTitle(R.string.dialog_web_view_outdated)
+                setMessage(R.string.dialog_web_view_outdated_message)
+                setCancelable(false)
+
+                val webViewPackage = WebViewCompat.getCurrentWebViewPackage(context)
+                if (webViewPackage != null) {
+                    setPositiveButton(R.string.dialog_button_check_for_updates) { _, _ ->
+                        val marketUri = Uri.Builder().apply {
+                            scheme("market")
+                            authority("details")
+                            appendQueryParameter("id", webViewPackage.packageName)
+                        }.build()
+                        val referrerUri = Uri.Builder().apply {
+                            scheme("android-app")
+                            authority(context.packageName)
+                        }.build()
+
+                        val marketIntent = Intent(Intent.ACTION_VIEW).apply {
+                            data = marketUri
+                            putExtra(Intent.EXTRA_REFERRER, referrerUri)
+                        }
+                        startActivity(marketIntent)
+                        requireActivity().finish()
+                    }
+                }
+                setNegativeButton(R.string.dialog_button_close_app) { _, _ ->
+                    requireActivity().finish()
+                }
+            }.show()
+            return
+        }
+
         webViewClient = object : WebViewClientCompat() {
             override fun shouldInterceptRequest(webView: WebView, request: WebResourceRequest): WebResourceResponse? {
                 val url = request.url
@@ -186,10 +220,7 @@ class WebViewFragment : Fragment(), NativePlayerHost {
             }
         }
         webChromeClient = WebChromeClient()
-        settings.apply {
-            javaScriptEnabled = true
-            domStorageEnabled = true
-        }
+        settings.applyDefault()
         addJavascriptInterface(NativeInterface(this@WebViewFragment), "NativeInterface")
         addJavascriptInterface(NativePlayer(this@WebViewFragment), "NativePlayer")
         addJavascriptInterface(externalPlayer, "ExternalPlayer")

app/src/main/java/org/jellyfin/mobile/utils/Constants.kt

@@ -9,6 +9,7 @@ object Constants {
     const val APP_INFO_VERSION: String = BuildConfig.VERSION_NAME
 
     // Webapp constants
+    const val MINIMUM_WEB_VIEW_VERSION = 88
     const val WEB_CONFIG_PATH = "config.json"
     const val CAST_SDK_PATH = "cast_sender.js"
     const val SESSION_CAPABILITIES_PATH = "sessions/capabilities/full"

app/src/main/java/org/jellyfin/mobile/utils/WebViewUtils.kt

@@ -0,0 +1,68 @@
+/**
+ * Taken and adapted from https://github.com/tachiyomiorg/tachiyomi/blob/master/app/src/main/java/eu/kanade/tachiyomi/util/system/WebViewUtil.kt
+ *
+ * Copyright 2015 Javier Tomás
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.jellyfin.mobile.utils
+
+import android.annotation.SuppressLint
+import android.content.Context
+import android.content.pm.PackageManager
+import android.webkit.CookieManager
+import android.webkit.WebSettings
+import android.webkit.WebView
+import timber.log.Timber
+
+fun Context.isWebViewSupported(): Boolean {
+    try {
+        // May throw android.webkit.WebViewFactory$MissingWebViewPackageException if WebView
+        // is not installed
+        CookieManager.getInstance()
+    } catch (e: Throwable) {
+        Timber.e(e)
+        return false
+    }
+
+    return packageManager.hasSystemFeature(PackageManager.FEATURE_WEBVIEW)
+}
+
+fun WebView.isOutdated(): Boolean =
+    getWebViewMajorVersion() < Constants.MINIMUM_WEB_VIEW_VERSION
+
+private fun WebView.getWebViewMajorVersion(): Int {
+    return """.*Chrome/(\d+)\..*""".toRegex().matchEntire(getDefaultUserAgentString())?.let { match ->
+        match.groupValues.getOrNull(1)?.toInt()
+    } ?: 0
+}
+
+// Based on https://stackoverflow.com/a/29218966
+private fun WebView.getDefaultUserAgentString(): String {
+    val originalUA: String = settings.userAgentString
+
+    // Next call to getUserAgentString() will get us the default
+    settings.userAgentString = null
+    val defaultUserAgentString = settings.userAgentString
+
+    // Revert to original UA string
+    settings.userAgentString = originalUA
+
+    return defaultUserAgentString
+}
+
+@SuppressLint("SetJavaScriptEnabled")
+fun WebSettings.applyDefault() {
+    javaScriptEnabled = true
+    domStorageEnabled = true
+}

app/src/main/res/values/strings.xml

@@ -1,4 +1,11 @@
 <resources xmlns:tools="http://schemas.android.com/tools" tools:ignore="MissingTranslation">
+    <string name="dialog_web_view_not_supported">WebView not supported</string>
+    <string name="dialog_web_view_not_supported_message">WebViews are not supported by this device.\nInstall a compatible WebView implementation or switch to a supported device.</string>
+    <string name="dialog_web_view_outdated">WebView outdated</string>
+    <string name="dialog_web_view_outdated_message">The WebView implementation used by your device is outdated.\nPlease update it to a compatible version.</string>
+    <string name="dialog_button_check_for_updates">Check for updates</string>
+    <string name="dialog_button_close_app">Close app</string>
+
     <string name="connect_to_server_title">Connect to Server</string>
     <string name="host_input_hint">Host</string>
     <string name="connection_error_invalid_format">Host has an invalid format</string>