Introduce AsyncView to limit duplicated code.

libraries/designsystem/build.gradle.kts

@@ -39,6 +39,7 @@ android {
         // Should not be there, but this is a POC
         implementation(libs.coil.compose)
         implementation(libs.vanniktech.blurhash)
+        implementation(projects.libraries.architecture)
         implementation(projects.libraries.testtags)
         implementation(projects.libraries.uiStrings)
 

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/components/async/AsyncProvider.kt

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * 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 io.element.android.libraries.designsystem.components.async
+
+import androidx.compose.ui.tooling.preview.PreviewParameterProvider
+import io.element.android.libraries.architecture.Async
+
+open class AsyncProvider : PreviewParameterProvider<Async<Unit>> {
+    override val values: Sequence<Async<Unit>>
+        get() = sequenceOf(
+            Async.Uninitialized,
+            Async.Loading(),
+            Async.Failure(Exception("An error occurred")),
+            Async.Success(Unit),
+        )
+}

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/components/async/AsyncView.kt

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * 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 io.element.android.libraries.designsystem.components.async
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.PreviewParameter
+import io.element.android.libraries.architecture.Async
+import io.element.android.libraries.designsystem.components.ProgressDialog
+import io.element.android.libraries.designsystem.components.dialogs.ErrorDialog
+import io.element.android.libraries.designsystem.components.dialogs.RetryDialog
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
+
+/**
+ * Render an Async object.
+ * - If Success, invoke the callback [onSuccess], only once.
+ * - If Failure, display a dialog with the error, which can be transformed, using [errorTransform]. When
+ * closed, [onErrorDismiss] will be invoked. If [onRetry] is not null, a retry button will be displayed.
+ * - When loading, display a loading dialog, if [showProgressDialog] is true, with on optional [progressText].
+ */
+@Composable
+fun <T> AsyncView(
+    async: Async<T>,
+    onSuccess: (T) -> Unit,
+    onErrorDismiss: () -> Unit,
+    modifier: Modifier = Modifier,
+    showProgressDialog: Boolean = true,
+    progressText: String? = null,
+    errorTransform: (Throwable) -> String = { it.message ?: it.toString() },
+    onRetry: (() -> Unit)? = null,
+) {
+    when (async) {
+        Async.Uninitialized -> Unit
+        is Async.Loading -> {
+            if (showProgressDialog) {
+                ProgressDialog(
+                    modifier = modifier,
+                    text = progressText,
+                )
+            }
+        }
+        is Async.Failure -> {
+            if (onRetry == null) {
+                ErrorDialog(
+                    modifier = modifier,
+                    content = errorTransform(async.error),
+                    onDismiss = onErrorDismiss
+                )
+            } else {
+                RetryDialog(
+                    modifier = modifier,
+                    content = errorTransform(async.error),
+                    onDismiss = onErrorDismiss,
+                    onRetry = onRetry,
+                )
+            }
+        }
+        is Async.Success -> {
+            LaunchedEffect(async) {
+                onSuccess(async.data)
+            }
+        }
+    }
+}
+
+@PreviewsDayNight
+@Composable
+internal fun AsyncViewPreview(
+    @PreviewParameter(AsyncProvider::class) async: Async<Unit>,
+) = ElementPreview {
+    AsyncView(
+        async = async,
+        onSuccess = {},
+        onErrorDismiss = {},
+    )
+}