feat(join by alias) : introduce the JoinRoomByAddress

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/CreateRoomNavigator.kt

@@ -19,10 +19,13 @@ import io.element.android.libraries.matrix.api.core.RoomIdOrAlias
 interface CreateRoomNavigator : Plugin {
     fun onOpenRoom(roomIdOrAlias: RoomIdOrAlias)
     fun onCreateNewRoom()
+    fun onShowJoinRoomByAddress()
+    fun onDismissJoinRoomByAddress()
 }
 
 class DefaultCreateRoomNavigator(
     private val backstack: BackStack<NavTarget>,
+    private val overlay: Overlay<NavTarget>,
     private val openRoom: (RoomIdOrAlias) -> Unit,
 ) : CreateRoomNavigator {
 
@@ -32,4 +35,11 @@ class DefaultCreateRoomNavigator(
         backstack.push(NavTarget.NewRoom)
     }
 
+    override fun onShowJoinRoomByAddress() {
+        overlay.show(NavTarget.JoinByAddress)
+    }
+
+    override fun onDismissJoinRoomByAddress() {
+        overlay.hide()
+    }
 }

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/CreateRoomFlowNode.kt

@@ -8,6 +8,7 @@
 package io.element.android.features.createroom.impl
 
 import android.os.Parcelable
+import androidx.compose.foundation.layout.Box
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
@@ -22,9 +23,11 @@ import dagger.assisted.AssistedInject
 import io.element.android.anvilannotations.ContributesNode
 import io.element.android.features.createroom.DefaultCreateRoomNavigator
 import io.element.android.features.createroom.api.CreateRoomEntryPoint
+import io.element.android.features.createroom.impl.joinbyaddress.JoinRoomByAddressNode
 import io.element.android.features.createroom.impl.root.CreateRoomRootNode
 import io.element.android.libraries.architecture.BackstackView
 import io.element.android.libraries.architecture.BaseFlowNode
+import io.element.android.libraries.architecture.OverlayView
 import io.element.android.libraries.architecture.createNode
 import io.element.android.libraries.di.SessionScope
 import io.element.android.libraries.matrix.api.core.RoomId
@@ -50,10 +53,13 @@ class CreateRoomFlowNode @AssistedInject constructor(
         @Parcelize
         data object NewRoom : NavTarget
 
+        @Parcelize
+        data object JoinByAddress : NavTarget
     }
 
     private val navigator = DefaultCreateRoomNavigator(
         backstack = backstack,
+        overlay = overlay,
         openRoom = { roomIdOrAlias ->
             plugins<CreateRoomEntryPoint.Callback>().forEach { it.onOpenRoom(roomIdOrAlias) }
         }
@@ -67,11 +73,17 @@ class CreateRoomFlowNode @AssistedInject constructor(
             NavTarget.NewRoom -> {
                 createNode<ConfigureRoomFlowNode>(buildContext = buildContext, plugins = listOf(navigator))
             }
+            NavTarget.JoinByAddress -> {
+                createNode<JoinRoomByAddressNode>(buildContext = buildContext, plugins = listOf(navigator))
+            }
         }
     }
 
     @Composable
     override fun View(modifier: Modifier) {
-        BackstackView()
+        Box(modifier = modifier) {
+            BackstackView()
+            OverlayView(transitionHandler = remember { JumpToEndTransitionHandler() })
+        }
     }
 }

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/joinbyaddress/JoinRoomByAddressEvents.kt

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.createroom.impl.joinbyaddress
+
+sealed interface JoinRoomByAddressEvents {
+    data object Dismiss : JoinRoomByAddressEvents
+    data object Continue: JoinRoomByAddressEvents
+    data class UpdateAddress(val address: String) : JoinRoomByAddressEvents
+}

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/joinbyaddress/JoinRoomByAddressNode.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.createroom.impl.joinbyaddress
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import com.bumble.appyx.core.modality.BuildContext
+import com.bumble.appyx.core.node.Node
+import com.bumble.appyx.core.plugin.Plugin
+import com.bumble.appyx.core.plugin.plugins
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedInject
+import io.element.android.anvilannotations.ContributesNode
+import io.element.android.features.createroom.CreateRoomNavigator
+import io.element.android.libraries.di.SessionScope
+
+@ContributesNode(SessionScope::class)
+class JoinRoomByAddressNode @AssistedInject constructor(
+    @Assisted buildContext: BuildContext,
+    @Assisted plugins: List<Plugin>,
+    presenterFactory: JoinRoomByAddressPresenter.Factory,
+) : Node(buildContext, plugins = plugins) {
+
+    private val navigator = plugins<CreateRoomNavigator>().first()
+    private val presenter = presenterFactory.create(navigator)
+
+    @Composable
+    override fun View(modifier: Modifier) {
+        val state = presenter.present()
+        JoinRoomByAddressView(
+            state = state,
+            modifier = modifier
+        )
+    }
+}

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/joinbyaddress/JoinRoomByAddressPresenter.kt

@@ -0,0 +1,98 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.createroom.impl.joinbyaddress
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberUpdatedState
+import androidx.compose.runtime.setValue
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+import io.element.android.features.createroom.CreateRoomNavigator
+import io.element.android.libraries.architecture.Presenter
+import io.element.android.libraries.core.data.tryOrNull
+import io.element.android.libraries.matrix.api.MatrixClient
+import io.element.android.libraries.matrix.api.core.RoomAlias
+import io.element.android.libraries.matrix.api.core.RoomIdOrAlias
+import io.element.android.libraries.matrix.api.room.alias.RoomAliasHelper
+import kotlinx.coroutines.delay
+
+class JoinRoomByAddressPresenter @AssistedInject constructor(
+    @Assisted private val navigator: CreateRoomNavigator,
+    private val client: MatrixClient,
+    private val roomAliasHelper: RoomAliasHelper,
+) : Presenter<JoinRoomByAddressState> {
+
+    @AssistedFactory
+    interface Factory {
+        fun create(navigator: CreateRoomNavigator): JoinRoomByAddressPresenter
+    }
+
+    @Composable
+    override fun present(): JoinRoomByAddressState {
+        var address by remember { mutableStateOf("") }
+        var addressState by remember { mutableStateOf<RoomAddressState>(RoomAddressState.Unknown) }
+
+        fun handleEvents(event: JoinRoomByAddressEvents) {
+            when (event) {
+                JoinRoomByAddressEvents.Continue -> {
+                    navigator.onDismissJoinRoomByAddress()
+                    navigator.onOpenRoom(RoomIdOrAlias.Alias(RoomAlias(address)))
+                }
+                JoinRoomByAddressEvents.Dismiss -> navigator.onDismissJoinRoomByAddress()
+                is JoinRoomByAddressEvents.UpdateAddress -> {
+                    address = event.address.trim()
+                }
+            }
+        }
+
+        RoomAddressStateEffect(
+            fullAddress = address,
+            onRoomAddressStateChange = { addressState = it }
+        )
+
+        return JoinRoomByAddressState(
+            address = address,
+            addressState = addressState,
+            eventSink = ::handleEvents
+        )
+    }
+
+    @Composable
+    private fun RoomAddressStateEffect(
+        fullAddress: String,
+        onRoomAddressStateChange: (RoomAddressState) -> Unit,
+    ) {
+        val onChange by rememberUpdatedState(onRoomAddressStateChange)
+        LaunchedEffect(fullAddress) {
+            if (fullAddress.isEmpty()) {
+                onChange(RoomAddressState.Unknown)
+                return@LaunchedEffect
+            }
+            // debounce the room address validation
+            delay(300)
+            val roomAlias = tryOrNull { RoomAlias(fullAddress) }
+            if (roomAlias == null || !roomAliasHelper.isRoomAliasValid(roomAlias)) {
+                onChange(RoomAddressState.Invalid)
+            } else {
+                onChange(RoomAddressState.Valid(matchingRoomFound = false))
+                client.resolveRoomAlias(roomAlias)
+                    .onSuccess { resolved ->
+                        onChange(RoomAddressState.Valid(matchingRoomFound = resolved.isPresent))
+                    }
+            }
+        }
+    }
+}
+
+
+

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/joinbyaddress/JoinRoomByAddressState.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.createroom.impl.joinbyaddress
+
+import androidx.compose.runtime.Immutable
+
+data class JoinRoomByAddressState(
+    val address: String,
+    val addressState: RoomAddressState,
+    val eventSink: (JoinRoomByAddressEvents) -> Unit
+)
+
+@Immutable
+sealed interface RoomAddressState {
+    data object Unknown : RoomAddressState
+    data object Invalid : RoomAddressState
+    data class Valid(val matchingRoomFound: Boolean) : RoomAddressState
+}

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/joinbyaddress/JoinRoomByAddressStateProvider.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.createroom.impl.joinbyaddress
+
+import androidx.compose.ui.tooling.preview.PreviewParameterProvider
+
+open class JoinRoomByAddressStateProvider : PreviewParameterProvider<JoinRoomByAddressState> {
+    override val values: Sequence<JoinRoomByAddressState>
+        get() = sequenceOf(
+            aJoinRoomByAddressState(),
+            aJoinRoomByAddressState("#room-"),
+            aJoinRoomByAddressState("#room-", addressState = RoomAddressState.Invalid),
+            aJoinRoomByAddressState("#room-name:matrix.org", addressState = RoomAddressState.Valid(true)),
+            aJoinRoomByAddressState("#room-name-here:matrix.org", addressState = RoomAddressState.Valid(false)),
+            // Add other states here
+        )
+}
+
+fun aJoinRoomByAddressState(
+    address: String = "",
+    addressState: RoomAddressState = RoomAddressState.Unknown,
+) = JoinRoomByAddressState(
+    address = address,
+    addressState = addressState,
+    eventSink = {}
+)

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/joinbyaddress/JoinRoomByAddressView.kt

@@ -0,0 +1,114 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.createroom.impl.joinbyaddress
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.rememberModalBottomSheetState
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.PreviewParameter
+import androidx.compose.ui.unit.dp
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
+import io.element.android.libraries.designsystem.theme.components.Button
+import io.element.android.libraries.designsystem.theme.components.ModalBottomSheet
+import io.element.android.libraries.designsystem.theme.components.TextField
+import io.element.android.libraries.ui.strings.CommonStrings
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun JoinRoomByAddressView(
+    state: JoinRoomByAddressState,
+    modifier: Modifier = Modifier,
+) {
+    val sheetState = rememberModalBottomSheetState(skipPartiallyExpanded = true)
+    ModalBottomSheet(
+        modifier = modifier,
+        sheetState = sheetState,
+        onDismissRequest = {
+            state.eventSink(JoinRoomByAddressEvents.Dismiss)
+        },
+    ) {
+        Column(
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(all = 16.dp),
+            horizontalAlignment = Alignment.CenterHorizontally,
+        ) {
+            RoomAddressField(
+                address = state.address,
+                addressState = state.addressState,
+                requestFocus = sheetState.isVisible,
+                onAddressChange = {
+                    state.eventSink(JoinRoomByAddressEvents.UpdateAddress(it))
+                }
+            )
+            Spacer(modifier = Modifier.height(24.dp))
+            Button(
+                text = stringResource(CommonStrings.action_continue),
+                modifier = Modifier.fillMaxWidth(),
+                enabled = state.addressState is RoomAddressState.Valid,
+                onClick = {
+                    state.eventSink(JoinRoomByAddressEvents.Continue)
+                }
+            )
+        }
+    }
+}
+
+@Composable
+private fun RoomAddressField(
+    address: String,
+    addressState: RoomAddressState,
+    requestFocus: Boolean,
+    onAddressChange: (String) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val focusRequester = remember { FocusRequester() }
+    if (requestFocus) {
+        LaunchedEffect(Unit) { focusRequester.requestFocus() }
+    }
+    TextField(
+        modifier = modifier.focusRequester(focusRequester),
+        value = address,
+        label = "Join room by address",
+        placeholder = "Enter...",
+        supportingText = when (addressState) {
+            RoomAddressState.Invalid -> "Not a valid address"
+            RoomAddressState.Unknown -> "e.g. #room-name:matrix.org"
+            is RoomAddressState.Valid -> if (addressState.matchingRoomFound) {
+                "Matching room found"
+            } else {
+                "e.g. #room-name:matrix.org"
+            }
+        },
+        isError = addressState is RoomAddressState.Invalid,
+        onValueChange = onAddressChange,
+        singleLine = true,
+    )
+}
+
+@PreviewsDayNight
+@Composable
+internal fun JoinRoomByAddressViewPreview(
+    @PreviewParameter(JoinRoomByAddressStateProvider::class) state: JoinRoomByAddressState
+) = ElementPreview {
+    JoinRoomByAddressView(state = state)
+}
+

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/root/CreateRoomRootNode.kt

@@ -55,6 +55,7 @@ class CreateRoomRootNode @AssistedInject constructor(
             onOpenDM = {
                 navigator.onOpenRoom(it.toRoomIdOrAlias())
             },
+            onJoinByAddressClick = navigator::onShowJoinRoomByAddress,
             onInviteFriendsClick = { invitePeople(activity) }
         )
     }

features/createroom/impl/src/main/kotlin/io/element/android/features/createroom/impl/root/CreateRoomRootView.kt

@@ -55,6 +55,7 @@ fun CreateRoomRootView(
     onNewRoomClick: () -> Unit,
     onOpenDM: (RoomId) -> Unit,
     onInviteFriendsClick: () -> Unit,
+    onJoinByAddressClick: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
     Scaffold(
@@ -89,6 +90,7 @@ fun CreateRoomRootView(
                     state = state,
                     onNewRoomClick = onNewRoomClick,
                     onInvitePeopleClick = onInviteFriendsClick,
+                    onJoinByAddressClick = onJoinByAddressClick,
                     onDmClick = onOpenDM,
                 )
             }
@@ -153,6 +155,7 @@ private fun CreateRoomActionButtonsList(
     state: CreateRoomRootState,
     onNewRoomClick: () -> Unit,
     onInvitePeopleClick: () -> Unit,
+    onJoinByAddressClick: () -> Unit,
     onDmClick: (RoomId) -> Unit,
 ) {
     LazyColumn {
@@ -170,6 +173,13 @@ private fun CreateRoomActionButtonsList(
                 onClick = onInvitePeopleClick,
             )
         }
+        item {
+            CreateRoomActionButton(
+                iconRes = CompoundDrawables.ic_compound_mention,
+                text = "Join room by address",
+                onClick = onJoinByAddressClick,
+            )
+        }
         if (state.userListState.recentDirectRooms.isNotEmpty()) {
             item {
                 ListSectionHeader(
@@ -230,6 +240,7 @@ internal fun CreateRoomRootViewPreview(@PreviewParameter(CreateRoomRootStateProv
             onCloseClick = {},
             onNewRoomClick = {},
             onOpenDM = {},
+            onJoinByAddressClick = {},
             onInviteFriendsClick = {},
         )
     }