feat: App Level WebView/No Internet Error Handling

core/src/main/java/org/openedx/core/extension/StringExt.kt

@@ -1,6 +1,7 @@
 package org.openedx.core.extension
 
 import android.util.Patterns
+import java.net.URL
 import java.util.Locale
 import java.util.regex.Pattern
 
@@ -38,6 +39,14 @@ fun String.takeIfNotEmpty(): String? {
     return if (this.isEmpty().not()) this else null
 }
 
+fun String?.equalsHost(host: String?): Boolean {
+    return try {
+        host?.startsWith(URL(this).host, ignoreCase = true) == true
+    } catch (e: Exception) {
+        false
+    }
+}
+
 fun String.toImageLink(apiHostURL: String): String =
     if (this.isLinkValid()) {
         this

core/src/main/java/org/openedx/core/presentation/global/ErrorType.kt

@@ -0,0 +1,23 @@
+package org.openedx.core.presentation.global
+
+import org.openedx.core.R
+
+enum class ErrorType(
+    val iconResId: Int = 0,
+    val titleResId: Int = 0,
+    val descriptionResId: Int = 0,
+    val actionResId: Int = 0,
+) {
+    CONNECTION_ERROR(
+        iconResId = R.drawable.core_no_internet_connection,
+        titleResId = R.string.core_no_internet_connection,
+        descriptionResId = R.string.core_no_internet_connection_description,
+        actionResId = R.string.core_reload,
+    ),
+    UNKNOWN_ERROR(
+        iconResId = R.drawable.core_ic_unknown_error,
+        titleResId = R.string.core_try_again,
+        descriptionResId = R.string.core_something_went_wrong_description,
+        actionResId = R.string.core_reload,
+    ),
+}

core/src/main/java/org/openedx/core/presentation/global/webview/WebViewUIState.kt

@@ -0,0 +1,15 @@
+package org.openedx.core.presentation.global.webview
+
+import org.openedx.core.presentation.global.ErrorType
+
+sealed class WebViewUIState {
+    data object Loading : WebViewUIState()
+    data object Loaded : WebViewUIState()
+    data class Error(val errorType: ErrorType) : WebViewUIState()
+}
+
+enum class WebViewUIAction {
+    WEB_PAGE_LOADED,
+    WEB_PAGE_ERROR,
+    RELOAD_WEB_PAGE
+}

core/src/main/java/org/openedx/core/ui/ComposeCommon.kt

@@ -109,6 +109,7 @@ import org.openedx.core.domain.model.RegistrationField
 import org.openedx.core.extension.LinkedImageText
 import org.openedx.core.extension.tagId
 import org.openedx.core.extension.toastMessage
+import org.openedx.core.presentation.global.ErrorType
 import org.openedx.core.ui.theme.OpenEdXTheme
 import org.openedx.core.ui.theme.appColors
 import org.openedx.core.ui.theme.appShapes
@@ -1136,33 +1137,41 @@ fun BackBtn(
 }
 
 @Composable
-fun ConnectionErrorView(
-    modifier: Modifier,
-    onReloadClick: () -> Unit,
+fun ConnectionErrorView(onReloadClick: () -> Unit) {
+    FullScreenErrorView(errorType = ErrorType.CONNECTION_ERROR, onReloadClick = onReloadClick)
+}
+
+@Composable
+fun FullScreenErrorView(
+    modifier: Modifier = Modifier,
+    errorType: ErrorType,
+    onReloadClick: () -> Unit
 ) {
     Column(
-        modifier = modifier,
+        modifier = modifier
+            .fillMaxSize()
+            .background(MaterialTheme.appColors.background),
         verticalArrangement = Arrangement.Center,
         horizontalAlignment = Alignment.CenterHorizontally
     ) {
         Icon(
             modifier = Modifier.size(100.dp),
-            painter = painterResource(id = R.drawable.core_no_internet_connection),
+            painter = painterResource(id = errorType.iconResId),
             contentDescription = null,
             tint = MaterialTheme.appColors.onSurface
         )
         Spacer(Modifier.height(28.dp))
         Text(
             modifier = Modifier.fillMaxWidth(0.8f),
-            text = stringResource(id = R.string.core_no_internet_connection),
+            text = stringResource(id = errorType.titleResId),
             color = MaterialTheme.appColors.textPrimary,
             style = MaterialTheme.appTypography.titleLarge,
             textAlign = TextAlign.Center
         )
         Spacer(Modifier.height(16.dp))
         Text(
             modifier = Modifier.fillMaxWidth(0.8f),
-            text = stringResource(id = R.string.core_no_internet_connection_description),
+            text = stringResource(id = errorType.descriptionResId),
             color = MaterialTheme.appColors.textPrimary,
             style = MaterialTheme.appTypography.bodyLarge,
             textAlign = TextAlign.Center
@@ -1171,7 +1180,7 @@ fun ConnectionErrorView(
         OpenEdXButton(
             modifier = Modifier
                 .widthIn(Dp.Unspecified, 162.dp),
-            text = stringResource(id = R.string.core_reload),
+            text = stringResource(id = errorType.actionResId),
             textColor = MaterialTheme.appColors.primaryButtonText,
             backgroundColor = MaterialTheme.appColors.secondaryButtonBackground,
             onClick = onReloadClick,
@@ -1372,11 +1381,7 @@ private fun IconTextPreview() {
 @Composable
 private fun ConnectionErrorViewPreview() {
     OpenEdXTheme(darkTheme = true) {
-        ConnectionErrorView(
-            modifier = Modifier
-                .fillMaxSize(),
-            onReloadClick = {}
-        )
+        ConnectionErrorView(onReloadClick = {})
     }
 }
 

core/src/main/res/drawable/core_ic_unknown_error.xml

@@ -0,0 +1,23 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="86dp"
+    android:height="86dp"
+    android:viewportWidth="100"
+    android:viewportHeight="100">
+
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M85,61.35V20.67C85,18.09 82.91,16 80.33,16H19.67C17.09,16 15,18.09 15,20.67V61.35C15,62 15.52,62.52 16.17,62.52H83.83C84.48,62.52 85,62 85,61.35ZM55.74,34.47C55.28,34.01 55.29,33.25 55.77,32.8C56.23,32.36 56.97,32.4 57.43,32.86L58.44,33.87C58.67,34.1 59.04,34.1 59.26,33.87L60.28,32.86C60.73,32.4 61.47,32.36 61.93,32.8C62.42,33.25 62.42,34.01 61.96,34.47L60.91,35.52C60.69,35.75 60.69,36.11 60.91,36.34L61.93,37.36C62.68,38.11 62.19,39.38 61.14,39.38C60.84,39.38 60.54,39.27 60.31,39.04L59.26,37.99C59.04,37.76 58.67,37.76 58.44,37.99L57.39,39.04C56.92,39.52 56.13,39.49 55.68,38.98C55.28,38.51 55.33,37.8 55.77,37.36L56.79,36.34C57.02,36.11 57.02,35.75 56.79,35.52L55.74,34.47ZM59.67,50.9C60.41,51.63 59.89,52.9 58.85,52.9C58.56,52.9 58.26,52.78 58.03,52.56C54.93,49.52 51.1,49.28 50,49.28C45.65,49.28 42.75,51.79 41.97,52.56C41.51,53.01 40.77,53.01 40.32,52.55C39.86,52.09 39.87,51.35 40.33,50.9C45.81,45.52 54.43,45.75 59.67,50.9ZM38.04,34.47C37.58,34.01 37.58,33.25 38.07,32.8C38.53,32.36 39.27,32.4 39.72,32.86L40.74,33.87C40.96,34.1 41.33,34.1 41.56,33.87L42.57,32.86C43.02,32.4 43.77,32.36 44.23,32.8C44.71,33.25 44.72,34.01 44.26,34.47L43.21,35.52C42.98,35.75 42.98,36.11 43.21,36.34L44.23,37.36C44.98,38.11 44.49,39.38 43.43,39.38C43.13,39.38 42.84,39.27 42.61,39.04L41.56,37.99C41.33,37.76 40.96,37.76 40.74,37.99L39.69,39.04C39.21,39.52 38.43,39.49 37.98,38.98C37.58,38.51 37.63,37.8 38.07,37.36L39.09,36.34C39.31,36.11 39.31,35.75 39.09,35.52L38.04,34.47Z" />
+
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M15,66.02V67.48C15,70.06 17.09,72.15 19.67,72.15H80.33C82.88,72.15 84.96,70.09 85,67.55V66.02C85,65.38 84.48,64.85 83.83,64.85H16.17C15.52,64.85 15,65.38 15,66.02Z" />
+
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M32.55,83.28C32.36,82.67 32.71,82.01 33.32,81.82C43.55,78.64 56.47,78.65 66.68,81.82C67.3,82.01 67.64,82.67 67.45,83.28C67.26,83.9 66.6,84.24 65.99,84.05C56.28,81.03 43.72,81.03 34.01,84.05C33.4,84.24 32.74,83.9 32.55,83.28Z" />
+
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M56.92,77.47C52.43,76.98 47.67,76.97 43.08,77.47C42.26,77.56 41.61,76.79 41.83,75.99L42.02,75.33C42.16,74.83 42.62,74.48 43.14,74.48H56.86C57.38,74.48 57.84,74.83 57.98,75.33L58.17,75.99C58.39,76.79 57.74,77.56 56.92,77.47Z" />
+
+</vector>

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

@@ -75,6 +75,8 @@
     <string name="core_thank_you_dialog_negative_description">We received your feedback and will use it to help improve your learning experience going forward. Thank you for sharing!</string>
     <string name="core_no_internet_connection">No internet connection</string>
     <string name="core_no_internet_connection_description">Please connect to the internet to view this content.</string>
+    <string name="core_try_again">Try Again</string>
+    <string name="core_something_went_wrong_description">Something went wrong</string>
     <string name="core_ok" tools:ignore="MissingTranslation">OK</string>
     <string name="core_continue" tools:ignore="MissingTranslation">Continue</string>
     <string name="core_leaving_the_app" tools:ignore="MissingTranslation">Leaving the app</string>

course/src/main/java/org/openedx/course/presentation/unit/html/HtmlUnitFragment.kt

@@ -10,6 +10,7 @@ import android.util.Log
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import android.webkit.JavascriptInterface
+import android.webkit.WebResourceError
 import android.webkit.WebResourceRequest
 import android.webkit.WebResourceResponse
 import android.webkit.WebSettings
@@ -18,7 +19,6 @@ import android.webkit.WebViewClient
 import androidx.compose.foundation.background
 import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.fillMaxHeight
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
@@ -53,10 +53,11 @@ import kotlinx.coroutines.launch
 import org.koin.androidx.viewmodel.ext.android.viewModel
 import org.koin.core.parameter.parametersOf
 import org.openedx.core.extension.applyDarkModeIfEnabled
+import org.openedx.core.extension.equalsHost
 import org.openedx.core.extension.isEmailValid
 import org.openedx.core.extension.loadUrl
 import org.openedx.core.system.AppCookieManager
-import org.openedx.core.ui.ConnectionErrorView
+import org.openedx.core.ui.FullScreenErrorView
 import org.openedx.core.ui.WindowSize
 import org.openedx.core.ui.rememberWindowSize
 import org.openedx.core.ui.roundBorderWithoutBottom
@@ -96,10 +97,6 @@ class HtmlUnitFragment : Fragment() {
             OpenEdXTheme {
                 val windowSize = rememberWindowSize()
 
-                var isLoading by remember {
-                    mutableStateOf(true)
-                }
-
                 var hasInternetConnection by remember {
                     mutableStateOf(viewModel.isOnline)
                 }
@@ -148,49 +145,54 @@ class HtmlUnitFragment : Fragment() {
                             .then(border),
                         contentAlignment = Alignment.TopCenter
                     ) {
-                        if (uiState.isLoadingEnabled) {
+                        if (uiState is HtmlUnitUIState.Initialization) return@Box
+                        if ((uiState is HtmlUnitUIState.Error).not()) {
                             if (hasInternetConnection || fromDownloadedContent) {
                                 HTMLContentView(
                                     uiState = uiState,
                                     windowSize = windowSize,
                                     url = url,
                                     cookieManager = viewModel.cookieManager,
                                     apiHostURL = viewModel.apiHostURL,
-                                    isLoading = isLoading,
+                                    isLoading = uiState is HtmlUnitUIState.Loading,
                                     injectJSList = injectJSList,
                                     onCompletionSet = {
                                         viewModel.notifyCompletionSet()
                                     },
                                     onWebPageLoading = {
-                                        isLoading = true
+                                        viewModel.onWebPageLoading()
                                     },
                                     onWebPageLoaded = {
-                                        isLoading = false
+                                        if ((uiState is HtmlUnitUIState.Error).not()) {
+                                            viewModel.onWebPageLoaded()
+                                        }
                                         if (isAdded) viewModel.setWebPageLoaded(requireContext().assets)
                                     },
+                                    onWebPageLoadError = {
+                                        viewModel.onWebPageLoadError()
+                                    },
                                     saveXBlockProgress = { jsonProgress ->
                                         viewModel.saveXBlockProgress(jsonProgress)
                                     },
                                 )
                             } else {
-                                ConnectionErrorView(
-                                    modifier = Modifier
-                                        .fillMaxWidth()
-                                        .fillMaxHeight()
-                                        .background(MaterialTheme.appColors.background)
-                                ) {
-                                    hasInternetConnection = viewModel.isOnline
-                                }
+                                viewModel.onWebPageLoadError()
                             }
-                            if (isLoading && hasInternetConnection) {
-                                Box(
-                                    modifier = Modifier
-                                        .fillMaxSize()
-                                        .zIndex(1f),
-                                    contentAlignment = Alignment.Center
-                                ) {
-                                    CircularProgressIndicator(color = MaterialTheme.appColors.primary)
-                                }
+                        } else {
+                            val errorType = (uiState as HtmlUnitUIState.Error).errorType
+                            FullScreenErrorView(errorType = errorType) {
+                                hasInternetConnection = viewModel.isOnline
+                                viewModel.onWebPageLoading()
+                            }
+                        }
+                        if (uiState is HtmlUnitUIState.Loading && hasInternetConnection) {
+                            Box(
+                                modifier = Modifier
+                                    .fillMaxSize()
+                                    .zIndex(1f),
+                                contentAlignment = Alignment.Center
+                            ) {
+                                CircularProgressIndicator(color = MaterialTheme.appColors.primary)
                             }
                         }
                     }
@@ -239,7 +241,8 @@ private fun HTMLContentView(
     onCompletionSet: () -> Unit,
     onWebPageLoading: () -> Unit,
     onWebPageLoaded: () -> Unit,
-    saveXBlockProgress: (String) -> Unit
+    onWebPageLoadError: () -> Unit,
+    saveXBlockProgress: (String) -> Unit,
 ) {
     val coroutineScope = rememberCoroutineScope()
     val context = LocalContext.current
@@ -333,6 +336,17 @@ private fun HTMLContentView(
                         }
                         super.onReceivedHttpError(view, request, errorResponse)
                     }
+
+                    override fun onReceivedError(
+                        view: WebView,
+                        request: WebResourceRequest,
+                        error: WebResourceError
+                    ) {
+                        if (view.url.equalsHost(request.url.host)) {
+                            onWebPageLoadError()
+                        }
+                        super.onReceivedError(view, request, error)
+                    }
                 }
                 with(settings) {
                     javaScriptEnabled = true
@@ -356,7 +370,7 @@ private fun HTMLContentView(
         update = { webView ->
             if (!isLoading && injectJSList.isNotEmpty()) {
                 injectJSList.forEach { webView.evaluateJavascript(it, null) }
-                val jsonProgress = uiState.jsonProgress
+                val jsonProgress = (uiState as? HtmlUnitUIState.Loaded)?.jsonProgress
                 if (!jsonProgress.isNullOrEmpty()) {
                     webView.setupOfflineProgress(jsonProgress)
                 }

course/src/main/java/org/openedx/course/presentation/unit/html/HtmlUnitUIState.kt

@@ -1,6 +1,10 @@
 package org.openedx.course.presentation.unit.html
 
-data class HtmlUnitUIState(
-    val jsonProgress: String?,
-    val isLoadingEnabled: Boolean
-)
+import org.openedx.core.presentation.global.ErrorType
+
+sealed class HtmlUnitUIState {
+    data object Initialization : HtmlUnitUIState()
+    data object Loading : HtmlUnitUIState()
+    data class Loaded(val jsonProgress: String? = null) : HtmlUnitUIState()
+    data class Error(val errorType: ErrorType) : HtmlUnitUIState()
+}