Filter existing room members.

matrix-sdk-android-rx/src/main/java/im/vector/matrix/rx/RxSession.kt

@@ -81,8 +81,8 @@ class RxSession(private val session: Session) {
         return session.getIgnoredUsersLive().asObservable()
     }
 
-    fun livePagedUsers(filter: String? = null): Observable<PagedList<User>> {
+    fun livePagedUsers(filter: String? = null, excludedUserIds: Set<String>? = null): Observable<PagedList<User>> {
-        return session.getPagedUsersLive(filter).asObservable()
+        return session.getPagedUsersLive(filter, excludedUserIds).asObservable()
     }
 
     fun createRoom(roomParams: CreateRoomParams): Single<String> = singleBuilder {

matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/user/UserService.kt

@@ -63,7 +63,7 @@ interface UserService {
      * @param filter the filter. It will look into userId and displayName.
      * @return a Livedata of users
      */
-    fun getPagedUsersLive(filter: String? = null): LiveData<PagedList<User>>
+    fun getPagedUsersLive(filter: String? = null, excludedUserIds: Set<String>? = null): LiveData<PagedList<User>>
 
     /**
      * Get list of ignored users

matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/session/user/DefaultUserService.kt

@@ -91,7 +91,7 @@ internal class DefaultUserService @Inject constructor(private val monarchy: Mona
         )
     }
 
-    override fun getPagedUsersLive(filter: String?): LiveData<PagedList<User>> {
+    override fun getPagedUsersLive(filter: String?, excludedUserIds: Set<String>?): LiveData<PagedList<User>> {
         realmDataSourceFactory.updateQuery { realm ->
             val query = realm.where(UserEntity::class.java)
             if (filter.isNullOrEmpty()) {
@@ -104,6 +104,9 @@ internal class DefaultUserService @Inject constructor(private val monarchy: Mona
                         .contains(UserEntityFields.USER_ID, filter)
                         .endGroup()
             }
+            excludedUserIds?.let {
+                query.not().`in`(UserEntityFields.USER_ID, it.toTypedArray())
+            }
             query.sort(UserEntityFields.DISPLAY_NAME)
         }
         return monarchy.findAllPagedWithChanges(realmDataSourceFactory, livePagedListBuilder)

vector/src/main/java/im/vector/riotx/features/invite/InviteUsersToRoomActivity.kt

@@ -85,7 +85,8 @@ class InviteUsersToRoomActivity : SimpleFragmentActivity() {
                     KnownUsersFragment::class.java,
                     KnownUsersFragmentArgs(
                             title = getString(R.string.invite_users_to_room_title),
-                            menuResId = R.menu.vector_invite_users_to_room
+                            menuResId = R.menu.vector_invite_users_to_room,
+                            excludedUserIds = viewModel.getUserIdsOfRoomMembers()
                     )
             )
         }

vector/src/main/java/im/vector/riotx/features/invite/InviteUsersToRoomViewModel.kt

@@ -67,4 +67,8 @@ class InviteUsersToRoomViewModel @AssistedInject constructor(@Assisted
                     _viewEvents.post(InviteUsersToRoomViewEvents.Failure(it))
                 }).disposeOnClear()
     }
+
+    fun getUserIdsOfRoomMembers(): Set<String> {
+        return room.roomSummary()?.otherMemberIds?.toSet() ?: emptySet()
+    }
 }

vector/src/main/java/im/vector/riotx/features/userdirectory/KnownUsersFragmentArgs.kt

@@ -22,5 +22,6 @@ import kotlinx.android.parcel.Parcelize
 @Parcelize
 data class KnownUsersFragmentArgs(
         val title: String,
-        val menuResId: Int? = null
+        val menuResId: Int? = null,
+        val excludedUserIds: Set<String>? = null
 ) : Parcelable

vector/src/main/java/im/vector/riotx/features/userdirectory/UserDirectoryViewModel.kt

@@ -96,7 +96,7 @@ class UserDirectoryViewModel @AssistedInject constructor(@Assisted
         setState { copy(selectedUsers = selectedUsers) }
     }
 
-    private fun observeDirectoryUsers() {
+    private fun observeDirectoryUsers() = withState { state ->
         directoryUsersSearch
                 .debounce(300, TimeUnit.MILLISECONDS)
                 .switchMapSingle { search ->
@@ -104,7 +104,7 @@ class UserDirectoryViewModel @AssistedInject constructor(@Assisted
                         Single.just(emptyList())
                     } else {
                         session.rx()
-                                .searchUsersDirectory(search, 50, emptySet())
+                                .searchUsersDirectory(search, 50, state.excludedUserIds ?: emptySet())
                                 .map { users ->
                                     users.sortedBy { it.toMatrixItem().firstLetterOfDisplayName() }
                                 }
@@ -117,12 +117,12 @@ class UserDirectoryViewModel @AssistedInject constructor(@Assisted
                 .disposeOnClear()
     }
 
-    private fun observeKnownUsers() {
+    private fun observeKnownUsers() = withState { state ->
         knownUsersFilter
                 .throttleLast(300, TimeUnit.MILLISECONDS)
                 .observeOn(AndroidSchedulers.mainThread())
                 .switchMap {
-                    session.rx().livePagedUsers(it.orNull())
+                    session.rx().livePagedUsers(it.orNull(), state.excludedUserIds)
                 }
                 .execute { async ->
                     copy(

vector/src/main/java/im/vector/riotx/features/userdirectory/UserDirectoryViewState.kt

@@ -24,6 +24,7 @@ import com.airbnb.mvrx.Uninitialized
 import im.vector.matrix.android.api.session.user.model.User
 
 data class UserDirectoryViewState(
+        val excludedUserIds: Set<String>? = null,
         val knownUsers: Async<PagedList<User>> = Uninitialized,
         val directoryUsers: Async<List<User>> = Uninitialized,
         val selectedUsers: Set<User> = emptySet(),
@@ -34,7 +35,7 @@ data class UserDirectoryViewState(
         val menuResId: Int?
 ) : MvRxState {
 
-    constructor(args: KnownUsersFragmentArgs) : this(title = args.title, menuResId = args.menuResId)
+    constructor(args: KnownUsersFragmentArgs) : this(title = args.title, menuResId = args.menuResId, excludedUserIds = args.excludedUserIds)
 
     enum class DisplayMode {
         KNOWN_USERS,