feat(webview): optional unload on pause

app/src/main/java/io/homeassistant/companion/android/settings/SettingsPresenterImpl.kt

@@ -78,6 +78,7 @@ class SettingsPresenterImpl @Inject constructor(
             "crash_reporting" -> prefsRepository.isCrashReporting()
             "autoplay_video" -> prefsRepository.isAutoPlayVideoEnabled()
             "always_show_first_view_on_app_start" -> prefsRepository.isAlwaysShowFirstViewOnAppStartEnabled()
+            "unload_when_backgrounded" -> prefsRepository.isUnloadWhenBackgroundedEnabled()
             "assist_voice_command_intent" -> {
                 val componentSetting = view.getPackageManager()?.getComponentEnabledSetting(voiceCommandAppComponent)
                 componentSetting != null && componentSetting != PackageManager.COMPONENT_ENABLED_STATE_DISABLED
@@ -95,6 +96,7 @@ class SettingsPresenterImpl @Inject constructor(
                 "crash_reporting" -> prefsRepository.setCrashReporting(value)
                 "autoplay_video" -> prefsRepository.setAutoPlayVideo(value)
                 "always_show_first_view_on_app_start" -> prefsRepository.setAlwaysShowFirstViewOnAppStart(value)
+                "unload_when_backgrounded" -> prefsRepository.setUnloadWhenBackgroundedEnabled(value)
                 "assist_voice_command_intent" ->
                     view.getPackageManager()?.setComponentEnabledSetting(
                         voiceCommandAppComponent,

app/src/main/java/io/homeassistant/companion/android/webview/WebViewActivity.kt

@@ -887,7 +887,10 @@ class WebViewActivity : BaseActivity(), io.homeassistant.companion.android.webvi
 
     override fun onResume() {
         super.onResume()
-        if (currentAutoplay != presenter.isAutoPlayVideoEnabled()) {
+
+        if (presenter.isUnloadWhenBackgroundedEnabled()) {
+            restoreView()
+        } else if (currentAutoplay != presenter.isAutoPlayVideoEnabled()) {
             recreate()
         }
 
@@ -932,7 +935,12 @@ class WebViewActivity : BaseActivity(), io.homeassistant.companion.android.webvi
     override fun onPause() {
         super.onPause()
         presenter.setAppActive(false)
-        if (!isFinishing && !isRelaunching) SensorReceiver.updateAllSensors(this)
+        if (!isFinishing && !isRelaunching) {
+            if (presenter.isUnloadWhenBackgroundedEnabled()) {
+                unloadView()
+            }
+            SensorReceiver.updateAllSensors(this)
+        }
     }
 
     private suspend fun checkAndWarnForDisabledLocation() {
@@ -1088,6 +1096,36 @@ class WebViewActivity : BaseActivity(), io.homeassistant.companion.android.webvi
         exoPlayerView.requestLayout()
     }
 
+    /**
+     * Unload the view to stop video feeds and data usage.
+     */
+    private fun unloadView() {
+        if (webView.url == null) return
+        if (webView.url !== "about:blank") {
+            Log.d(TAG, "unloadView: the URL was ${webView.url} before unload, 'about:blank' the WebView to unload")
+            webView.loadUrl("about:blank")
+        } else {
+            Log.d(TAG, "unloadView: the URL is already unloaded")
+        }
+    }
+
+    /**
+     * Reload the view to restore previous suspended state.
+     */
+    private fun restoreView() {
+        if (webView.url == "about:blank") {
+            Log.d(TAG, "restoreView: the URL was previously unloaded")
+            if (webView.canGoBack()) {
+                webView.goBack()
+                Log.d(TAG, "restoreView: the WebView went back to ${webView.url}")
+            } else {
+                Log.w(TAG, "restoreView: the WebView cannot go back")
+            }
+        } else {
+            Log.d(TAG, "restoreView: the URL was not 'about:blank', no need to restore")
+        }
+    }
+
     fun processHaptic(hapticType: String) {
         val vm = getSystemService<Vibrator>()
 
@@ -1136,6 +1174,7 @@ class WebViewActivity : BaseActivity(), io.homeassistant.companion.android.webvi
             }
         }
     }
+
     private fun authenticationResult(result: Int) {
         when (result) {
             Authenticator.SUCCESS -> {

app/src/main/java/io/homeassistant/companion/android/webview/WebViewPresenter.kt

@@ -40,6 +40,7 @@ interface WebViewPresenter {
     fun isLockEnabled(): Boolean
     fun isAutoPlayVideoEnabled(): Boolean
     fun isAlwaysShowFirstViewOnAppStartEnabled(): Boolean
+    fun isUnloadWhenBackgroundedEnabled(): Boolean
 
     fun sessionTimeOut(): Int
 

app/src/main/java/io/homeassistant/companion/android/webview/WebViewPresenterImpl.kt

@@ -312,6 +312,10 @@ class WebViewPresenterImpl @Inject constructor(
         prefsRepository.isAlwaysShowFirstViewOnAppStartEnabled()
     }
 
+    override fun isUnloadWhenBackgroundedEnabled(): Boolean = runBlocking {
+        prefsRepository.isUnloadWhenBackgroundedEnabled()
+    }
+
     override fun onExternalBusMessage(message: JSONObject) {
         mainScope.launch {
             externalBusRepository.received(message)

app/src/main/res/xml/preferences.xml

@@ -75,6 +75,11 @@
             android:icon="@drawable/ic_home_variant_outline"
             android:title="@string/always_show_first_view_on_app_start"
             android:summary="@string/always_show_first_view_on_app_start_summary" />
+        <SwitchPreference
+            android:key="unload_when_backgrounded"
+            android:icon="@drawable/ic_visibility_off"
+            android:title="@string/unload_when_backgrounded"
+            android:summary="@string/unload_when_backgrounded_summary" />
         <Preference
             android:key="nfc_tags"
             android:icon="@drawable/ic_nfc"

common/src/main/java/io/homeassistant/companion/android/common/data/prefs/PrefsRepository.kt

@@ -61,6 +61,10 @@ interface PrefsRepository {
 
     suspend fun isAlwaysShowFirstViewOnAppStartEnabled(): Boolean
 
+    suspend fun isUnloadWhenBackgroundedEnabled(): Boolean
+
+    suspend fun setUnloadWhenBackgroundedEnabled(enabled: Boolean)
+
     suspend fun setAlwaysShowFirstViewOnAppStart(enabled: Boolean)
 
     suspend fun isWebViewDebugEnabled(): Boolean

common/src/main/java/io/homeassistant/companion/android/common/data/prefs/PrefsRepositoryImpl.kt

@@ -13,7 +13,7 @@ class PrefsRepositoryImpl @Inject constructor(
 
     companion object {
         private const val MIGRATION_PREF = "migration"
-        private const val MIGRATION_VERSION = 1
+        private const val MIGRATION_VERSION = 2
 
         private const val PREF_VER = "version"
         private const val PREF_THEME = "theme"
@@ -30,6 +30,7 @@ class PrefsRepositoryImpl @Inject constructor(
         private const val PREF_PINCH_TO_ZOOM_ENABLED = "pinch_to_zoom_enabled"
         private const val PREF_AUTOPLAY_VIDEO = "autoplay_video"
         private const val PREF_ALWAYS_SHOW_FIRST_VIEW_ON_APP_START = "always_show_first_view_on_app_start"
+        private const val PREF_UNLOAD_WHEN_BACKGROUNDED = "unload_when_backgrounded"
         private const val PREF_WEBVIEW_DEBUG_ENABLED = "webview_debug_enabled"
         private const val PREF_KEY_ALIAS = "key-alias"
         private const val PREF_CRASH_REPORTING_DISABLED = "crash_reporting"
@@ -42,7 +43,7 @@ class PrefsRepositoryImpl @Inject constructor(
     init {
         runBlocking {
             val currentVersion = localStorage.getInt(MIGRATION_PREF)
-            if (currentVersion == null || currentVersion < 1) {
+            if (currentVersion == null || currentVersion < MIGRATION_VERSION) {
                 integrationStorage.getString(PREF_CONTROLS_AUTH_REQUIRED)?.let {
                     localStorage.putString(PREF_CONTROLS_AUTH_REQUIRED, it)
                 }
@@ -64,6 +65,11 @@ class PrefsRepositoryImpl @Inject constructor(
                 integrationStorage.getBooleanOrNull(PREF_ALWAYS_SHOW_FIRST_VIEW_ON_APP_START)?.let {
                     localStorage.putBoolean(PREF_ALWAYS_SHOW_FIRST_VIEW_ON_APP_START, it)
                 }
+                integrationStorage.getBooleanOrNull(PREF_UNLOAD_WHEN_BACKGROUNDED)?.let { pref ->
+                    localStorage.putBoolean(PREF_UNLOAD_WHEN_BACKGROUNDED, pref)
+                } ?: run {
+                    localStorage.putBoolean(PREF_UNLOAD_WHEN_BACKGROUNDED, false)
+                }
                 integrationStorage.getBooleanOrNull(PREF_WEBVIEW_DEBUG_ENABLED)?.let {
                     localStorage.putBoolean(PREF_WEBVIEW_DEBUG_ENABLED, it)
                 }
@@ -193,6 +199,14 @@ class PrefsRepositoryImpl @Inject constructor(
         return localStorage.getBoolean(PREF_ALWAYS_SHOW_FIRST_VIEW_ON_APP_START)
     }
 
+    override suspend fun isUnloadWhenBackgroundedEnabled(): Boolean {
+        return localStorage.getBoolean(PREF_UNLOAD_WHEN_BACKGROUNDED)
+    }
+
+    override suspend fun setUnloadWhenBackgroundedEnabled(enabled: Boolean) {
+        localStorage.putBoolean(PREF_UNLOAD_WHEN_BACKGROUNDED, enabled)
+    }
+
     override suspend fun setAlwaysShowFirstViewOnAppStart(enabled: Boolean) {
         localStorage.putBoolean(PREF_ALWAYS_SHOW_FIRST_VIEW_ON_APP_START, enabled)
     }

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

@@ -25,6 +25,8 @@
     <string name="allow">Allow</string>
     <string name="always_show_first_view_on_app_start">Always show first view when opening app</string>
     <string name="always_show_first_view_on_app_start_summary">The first view of the default dashboard is shown as soon as the app is opened</string>
+    <string name="unload_when_backgrounded">Unload when the app is paused</string>
+    <string name="unload_when_backgrounded_summary">Unload any dashboard when the app is not in focus to prevent resource usage in the background (camera streams, etc.).</string>
     <string name="app_name">Home Assistant</string>
     <string name="app_version_info">App version info</string>
     <string name="application_version">Application version</string>