handle nullable on arguments extra

format code to match kotlin guidelines
remove redundant underscores on function destructuring
handle deprecated calls on lower android versions

app/src/main/java/chat/rocket/android/authentication/login/ui/LoginFragment.kt

@@ -58,10 +58,8 @@ class LoginFragment : Fragment(), LoginView {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
-
-        val bundle = arguments
-        if (bundle != null) {
-            serverName = bundle.getString(SERVER_NAME)
+        arguments?.run {
+            serverName = getString(SERVER_NAME)
         }
     }
 
@@ -150,7 +148,7 @@ class LoginFragment : Fragment(), LoginView {
     override fun showGenericErrorMessage() = showMessage(R.string.msg_generic_error)
 
     private fun setupOnClickListener() =
-        ui { _ ->
+        ui {
             button_log_in.setOnClickListener {
                 presenter.authenticateWithUserAndPassword(
                     text_username_or_email.textContent,
@@ -160,7 +158,7 @@ class LoginFragment : Fragment(), LoginView {
         }
 
     override fun showForgotPasswordView() {
-        ui { _ ->
+        ui {
             button_forgot_your_password.isVisible = true
             button_forgot_your_password.setOnClickListener { presenter.forgotPassword() }
 

app/src/main/java/chat/rocket/android/authentication/loginoptions/ui/LoginOptionsFragment.kt

@@ -157,34 +157,33 @@ class LoginOptionsFragment : Fragment(), LoginOptionsView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            serverName = bundle.getString(SERVER_NAME)
-            state = bundle.getString(STATE)
-            facebookOauthUrl = bundle.getString(FACEBOOK_OAUTH_URL)
-            githubOauthUrl = bundle.getString(GITHUB_OAUTH_URL)
-            googleOauthUrl = bundle.getString(GOOGLE_OAUTH_URL)
-            linkedinOauthUrl = bundle.getString(LINKEDIN_OAUTH_URL)
-            gitlabOauthUrl = bundle.getString(GITLAB_OAUTH_URL)
-            wordpressOauthUrl = bundle.getString(WORDPRESS_OAUTH_URL)
-            casLoginUrl = bundle.getString(CAS_LOGIN_URL)
-            casToken = bundle.getString(CAS_TOKEN)
-            casServiceName = bundle.getString(CAS_SERVICE_NAME)
-            casServiceNameTextColor = bundle.getInt(CAS_SERVICE_NAME_TEXT_COLOR)
-            casServiceButtonColor = bundle.getInt(CAS_SERVICE_BUTTON_COLOR)
-            customOauthUrl = bundle.getString(CUSTOM_OAUTH_URL)
-            customOauthServiceName = bundle.getString(CUSTOM_OAUTH_SERVICE_NAME)
-            customOauthServiceTextColor = bundle.getInt(CUSTOM_OAUTH_SERVICE_NAME_TEXT_COLOR)
-            customOauthServiceButtonColor = bundle.getInt(CUSTOM_OAUTH_SERVICE_BUTTON_COLOR)
-            samlUrl = bundle.getString(SAML_URL)
-            samlToken = bundle.getString(SAML_TOKEN)
-            samlServiceName = bundle.getString(SAML_SERVICE_NAME)
-            samlServiceTextColor = bundle.getInt(SAML_SERVICE_NAME_TEXT_COLOR)
-            samlServiceButtonColor = bundle.getInt(SAML_SERVICE_BUTTON_COLOR)
-            totalSocialAccountsEnabled = bundle.getInt(TOTAL_SOCIAL_ACCOUNTS)
-            isLoginFormEnabled = bundle.getBoolean(IS_LOGIN_FORM_ENABLED)
-            isNewAccountCreationEnabled = bundle.getBoolean(IS_NEW_ACCOUNT_CREATION_ENABLED)
-            deepLinkInfo = bundle.getParcelable(DEEP_LINK_INFO)
+        arguments?.run {
+            serverName = getString(SERVER_NAME)
+            state = getString(STATE)
+            facebookOauthUrl = getString(FACEBOOK_OAUTH_URL)
+            githubOauthUrl = getString(GITHUB_OAUTH_URL)
+            googleOauthUrl = getString(GOOGLE_OAUTH_URL)
+            linkedinOauthUrl = getString(LINKEDIN_OAUTH_URL)
+            gitlabOauthUrl = getString(GITLAB_OAUTH_URL)
+            wordpressOauthUrl = getString(WORDPRESS_OAUTH_URL)
+            casLoginUrl = getString(CAS_LOGIN_URL)
+            casToken = getString(CAS_TOKEN)
+            casServiceName = getString(CAS_SERVICE_NAME)
+            casServiceNameTextColor = getInt(CAS_SERVICE_NAME_TEXT_COLOR)
+            casServiceButtonColor = getInt(CAS_SERVICE_BUTTON_COLOR)
+            customOauthUrl = getString(CUSTOM_OAUTH_URL)
+            customOauthServiceName = getString(CUSTOM_OAUTH_SERVICE_NAME)
+            customOauthServiceTextColor = getInt(CUSTOM_OAUTH_SERVICE_NAME_TEXT_COLOR)
+            customOauthServiceButtonColor = getInt(CUSTOM_OAUTH_SERVICE_BUTTON_COLOR)
+            samlUrl = getString(SAML_URL)
+            samlToken = getString(SAML_TOKEN)
+            samlServiceName = getString(SAML_SERVICE_NAME)
+            samlServiceTextColor = getInt(SAML_SERVICE_NAME_TEXT_COLOR)
+            samlServiceButtonColor = getInt(SAML_SERVICE_BUTTON_COLOR)
+            totalSocialAccountsEnabled = getInt(TOTAL_SOCIAL_ACCOUNTS)
+            isLoginFormEnabled = getBoolean(IS_LOGIN_FORM_ENABLED)
+            isNewAccountCreationEnabled = getBoolean(IS_NEW_ACCOUNT_CREATION_ENABLED)
+            deepLinkInfo = getParcelable(DEEP_LINK_INFO)
         }
     }
 
@@ -388,7 +387,7 @@ class LoginOptionsFragment : Fragment(), LoginOptionsView {
     }
 
     override fun setupExpandAccountsView() {
-        ui { _ ->
+        ui {
             expand_more_accounts_container.isVisible = true
             var isAccountsCollapsed = true
             button_expand_collapse_accounts.setOnClickListener {
@@ -406,14 +405,14 @@ class LoginOptionsFragment : Fragment(), LoginOptionsView {
     }
 
     override fun showLoginWithEmailButton() {
-        ui { _ ->
+        ui {
             button_login_with_email.setOnClickListener { presenter.toLoginWithEmail() }
             button_login_with_email.isVisible = true
         }
     }
 
     override fun showCreateNewAccountButton() {
-        ui { _ ->
+        ui {
             button_create_an_account.setOnClickListener { presenter.toCreateAccount() }
             button_create_an_account.isVisible = true
         }

app/src/main/java/chat/rocket/android/authentication/registerusername/ui/RegisterUsernameFragment.kt

@@ -52,14 +52,10 @@ class RegisterUsernameFragment : Fragment(), RegisterUsernameView {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
-
-        val bundle = arguments
-        if (bundle != null) {
-            userId = bundle.getString(BUNDLE_USER_ID)
-            authToken = bundle.getString(BUNDLE_AUTH_TOKEN)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            userId = getString(BUNDLE_USER_ID, "")
+            authToken = getString(BUNDLE_AUTH_TOKEN, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/authentication/signup/ui/SignupFragment.kt

@@ -75,7 +75,7 @@ class SignupFragment : Fragment(), SignupView {
     }
 
     private fun setupOnClickListener() =
-        ui { _ ->
+        ui {
             button_register.setOnClickListener {
                 presenter.signup(
                     text_username.textContent,

app/src/main/java/chat/rocket/android/authentication/twofactor/ui/TwoFAFragment.kt

@@ -49,14 +49,10 @@ class TwoFAFragment : Fragment(), TwoFAView {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
-
-        val bundle = arguments
-        if (bundle != null) {
-            username = bundle.getString(BUNDLE_USERNAME)
-            password = bundle.getString(BUNDLE_PASSWORD)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            username = getString(BUNDLE_USERNAME, "")
+            password = getString(BUNDLE_PASSWORD, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/chatdetails/ui/ChatDetailsFragment.kt

@@ -66,15 +66,12 @@ class ChatDetailsFragment : Fragment(), ChatDetailsView {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
-            chatRoomType = bundle.getString(BUNDLE_CHAT_ROOM_TYPE)
-            isSubscribed = bundle.getBoolean(BUNDLE_IS_SUBSCRIBED)
-            disableMenu = bundle.getBoolean(BUNDLE_DISABLE_MENU)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID)
+            chatRoomType = getString(BUNDLE_CHAT_ROOM_TYPE)
+            isSubscribed = getBoolean(BUNDLE_IS_SUBSCRIBED)
+            disableMenu = getBoolean(BUNDLE_DISABLE_MENU)
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/chatinformation/ui/MessageInfoFragment.kt

@@ -46,12 +46,9 @@ class MessageInfoFragment : Fragment(), MessageInfoView {
         AndroidSupportInjection.inject(this)
         setHasOptionsMenu(true)
 
-        val bundle = arguments
-        if (bundle != null) {
-            messageId = bundle.getString(BUNDLE_MESSAGE_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            messageId = getString(BUNDLE_MESSAGE_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/chatroom/adapter/ActionsListAdapter.kt

@@ -12,7 +12,10 @@ import com.facebook.drawee.backends.pipeline.Fresco
 import kotlinx.android.synthetic.main.item_action_button.view.*
 import timber.log.Timber
 
-class ActionsListAdapter(actions: List<Action>, var actionAttachmentOnClickListener: ActionAttachmentOnClickListener) : RecyclerView.Adapter<ActionsListAdapter.ViewHolder>() {
+class ActionsListAdapter(
+        actions: List<Action>,
+        var actionAttachmentOnClickListener: ActionAttachmentOnClickListener
+) : RecyclerView.Adapter<ActionsListAdapter.ViewHolder>() {
 
     var actions: List<Action> = actions
 

app/src/main/java/chat/rocket/android/chatroom/adapter/ChatRoomAdapter.kt

@@ -174,12 +174,12 @@ class ChatRoomAdapter(
         Timber.d("index: $index")
         if (index > -1) {
             dataSet[index] = message
-            dataSet.forEachIndexed { index, viewModel ->
+            dataSet.forEachIndexed { ind, viewModel ->
                 if (viewModel.messageId == message.messageId) {
                     if (viewModel.nextDownStreamMessage == null) {
                         viewModel.reactions = message.reactions
                     }
-                    notifyItemChanged(index)
+                    notifyItemChanged(ind)
                 }
             }
             // Delete message only if current is a system message update, i.e.: Message Removed

app/src/main/java/chat/rocket/android/chatroom/adapter/RoomSuggestionsAdapter.kt

@@ -24,8 +24,8 @@ class RoomSuggestionsAdapter : SuggestionsAdapter<RoomSuggestionsViewHolder>("#"
         override fun bind(item: SuggestionModel, itemClickListener: SuggestionsAdapter.ItemClickListener?) {
             item as ChatRoomSuggestionUiModel
             with(itemView) {
-                val fullname = itemView.findViewById<TextView>(R.id.text_fullname)
-                val name = itemView.findViewById<TextView>(R.id.text_name)
+                val fullname = findViewById<TextView>(R.id.text_fullname)
+                val name = findViewById<TextView>(R.id.text_name)
                 name.text = item.name
                 fullname.text = item.fullName
                 setOnClickListener {

app/src/main/java/chat/rocket/android/chatroom/adapter/UrlPreviewViewHolder.kt

@@ -8,10 +8,11 @@ import chat.rocket.android.util.extensions.content
 import chat.rocket.android.util.extensions.openTabbedUrl
 import kotlinx.android.synthetic.main.message_url_preview.view.*
 
-class UrlPreviewViewHolder(itemView: View,
-                           listener: ActionsListener,
-                           reactionListener: EmojiReactionListener? = null)
-    : BaseViewHolder<UrlPreviewUiModel>(itemView, listener, reactionListener) {
+class UrlPreviewViewHolder(
+        itemView: View,
+        listener: ActionsListener,
+        reactionListener: EmojiReactionListener? = null
+) : BaseViewHolder<UrlPreviewUiModel>(itemView, listener, reactionListener) {
 
     init {
         with(itemView) {

app/src/main/java/chat/rocket/android/chatroom/presentation/ChatRoomPresenter.kt

@@ -1072,7 +1072,7 @@ class ChatRoomPresenter @Inject constructor(
         launchUI(strategy) {
             try {
                 messagesRepository.getById(messageId)?.let { message ->
-                    getChatRoomAsync(message.roomId)?.let { chatRoom ->
+                    getChatRoomAsync(message.roomId)?.let {
                         val models = mapper.map(message)
                         models.firstOrNull()?.permalink?.let {
                             view.copyToClipboard(it)

app/src/main/java/chat/rocket/android/chatroom/ui/ChatRoomActivity.kt

@@ -81,44 +81,46 @@ class ChatRoomActivity : AppCompatActivity(), HasSupportFragmentInjector {
             return
         }
 
-        val chatRoomId = intent.getStringExtra(INTENT_CHAT_ROOM_ID)
-        requireNotNull(chatRoomId) { "no chat_room_id provided in Intent extras" }
+        with(intent) {
+            val chatRoomId = getStringExtra(INTENT_CHAT_ROOM_ID)
+            requireNotNull(chatRoomId) { "no chat_room_id provided in Intent extras" }
 
-        val chatRoomName = intent.getStringExtra(INTENT_CHAT_ROOM_NAME)
-        requireNotNull(chatRoomName) { "no chat_room_name provided in Intent extras" }
+            val chatRoomName = getStringExtra(INTENT_CHAT_ROOM_NAME)
+            requireNotNull(chatRoomName) { "no chat_room_name provided in Intent extras" }
 
-        val chatRoomType = intent.getStringExtra(INTENT_CHAT_ROOM_TYPE)
-        requireNotNull(chatRoomType) { "no chat_room_type provided in Intent extras" }
+            val chatRoomType = getStringExtra(INTENT_CHAT_ROOM_TYPE)
+            requireNotNull(chatRoomType) { "no chat_room_type provided in Intent extras" }
 
-        val isReadOnly = intent.getBooleanExtra(INTENT_CHAT_ROOM_IS_READ_ONLY, true)
+            val isReadOnly = getBooleanExtra(INTENT_CHAT_ROOM_IS_READ_ONLY, true)
 
-        val isCreator = intent.getBooleanExtra(INTENT_CHAT_ROOM_IS_CREATOR, false)
+            val isCreator = getBooleanExtra(INTENT_CHAT_ROOM_IS_CREATOR, false)
 
-        val isFavorite = intent.getBooleanExtra(INTENT_CHAT_ROOM_IS_FAVORITE, false)
+            val isFavorite = getBooleanExtra(INTENT_CHAT_ROOM_IS_FAVORITE, false)
 
-        val chatRoomLastSeen = intent.getLongExtra(INTENT_CHAT_ROOM_LAST_SEEN, -1)
+            val chatRoomLastSeen = getLongExtra(INTENT_CHAT_ROOM_LAST_SEEN, -1)
 
-        val isSubscribed = intent.getBooleanExtra(INTENT_CHAT_IS_SUBSCRIBED, true)
+            val isSubscribed = getBooleanExtra(INTENT_CHAT_IS_SUBSCRIBED, true)
 
-        val chatRoomMessage = intent.getStringExtra(INTENT_CHAT_ROOM_MESSAGE)
+            val chatRoomMessage = getStringExtra(INTENT_CHAT_ROOM_MESSAGE)
 
-        setupToolbar()
-
-        if (supportFragmentManager.findFragmentByTag(TAG_CHAT_ROOM_FRAGMENT) == null) {
-            addFragment(TAG_CHAT_ROOM_FRAGMENT, R.id.fragment_container) {
-                newInstance(
-                    chatRoomId,
-                    chatRoomName,
-                    chatRoomType,
-                    isReadOnly,
-                    chatRoomLastSeen,
-                    isSubscribed,
-                    isCreator,
-                    isFavorite,
-                    chatRoomMessage
-                )
+            if (supportFragmentManager.findFragmentByTag(TAG_CHAT_ROOM_FRAGMENT) == null) {
+                addFragment(TAG_CHAT_ROOM_FRAGMENT, R.id.fragment_container) {
+                    newInstance(
+                            chatRoomId,
+                            chatRoomName,
+                            chatRoomType,
+                            isReadOnly,
+                            chatRoomLastSeen,
+                            isSubscribed,
+                            isCreator,
+                            isFavorite,
+                            chatRoomMessage
+                    )
+                }
             }
         }
+
+        setupToolbar()
     }
 
     override fun onBackPressed() {

app/src/main/java/chat/rocket/android/chatroom/ui/ChatRoomFragment.kt

@@ -273,20 +273,18 @@ class ChatRoomFragment : Fragment(), ChatRoomView, EmojiKeyboardListener, EmojiR
         AndroidSupportInjection.inject(this)
         setHasOptionsMenu(true)
 
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
-            chatRoomName = bundle.getString(BUNDLE_CHAT_ROOM_NAME)
-            chatRoomType = bundle.getString(BUNDLE_CHAT_ROOM_TYPE)
-            isReadOnly = bundle.getBoolean(BUNDLE_IS_CHAT_ROOM_READ_ONLY)
-            isSubscribed = bundle.getBoolean(BUNDLE_CHAT_ROOM_IS_SUBSCRIBED)
-            chatRoomLastSeen = bundle.getLong(BUNDLE_CHAT_ROOM_LAST_SEEN)
-            isCreator = bundle.getBoolean(BUNDLE_CHAT_ROOM_IS_CREATOR)
-            isFavorite = bundle.getBoolean(BUNDLE_CHAT_ROOM_IS_FAVORITE)
-            chatRoomMessage = bundle.getString(BUNDLE_CHAT_ROOM_MESSAGE)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID, "")
+            chatRoomName = getString(BUNDLE_CHAT_ROOM_NAME, "")
+            chatRoomType = getString(BUNDLE_CHAT_ROOM_TYPE, "")
+            isReadOnly = getBoolean(BUNDLE_IS_CHAT_ROOM_READ_ONLY)
+            isSubscribed = getBoolean(BUNDLE_CHAT_ROOM_IS_SUBSCRIBED)
+            chatRoomLastSeen = getLong(BUNDLE_CHAT_ROOM_LAST_SEEN)
+            isCreator = getBoolean(BUNDLE_CHAT_ROOM_IS_CREATOR)
+            isFavorite = getBoolean(BUNDLE_CHAT_ROOM_IS_FAVORITE)
+            chatRoomMessage = getString(BUNDLE_CHAT_ROOM_MESSAGE)
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
 
         adapter = ChatRoomAdapter(chatRoomId, chatRoomType, chatRoomName, this, reactionListener = this, navigator = navigator)
     }

app/src/main/java/chat/rocket/android/chatroom/ui/Dialog.kt

@@ -8,8 +8,7 @@ import chat.rocket.android.emoji.internal.GlideApp
 import chat.rocket.android.util.extensions.getFileName
 import chat.rocket.android.util.extensions.getMimeType
 import chat.rocket.common.util.ifNull
-import com.bumptech.glide.request.target.SimpleTarget
-import com.bumptech.glide.request.transition.Transition
+import com.bumptech.glide.request.target.ImageViewTarget
 
 fun ChatRoomFragment.showFileAttachmentDialog(uri: Uri) {
     imagePreview.isVisible = false
@@ -25,27 +24,22 @@ fun ChatRoomFragment.showFileAttachmentDialog(uri: Uri) {
             when {
                 mimeType.startsWith("image") -> {
                     if (mimeType.contains("gif")) {
-                        GlideApp
-                            .with(context)
-                            .asGif()
-                            .load(uri)
-                            .fitCenter()
-                            .into(imagePreview)
+                        GlideApp.with(context)
+                                .asGif()
+                                .load(uri)
+                                .fitCenter()
+                                .into(imagePreview)
                     } else {
-                        GlideApp
-                            .with(context)
-                            .asBitmap()
-                            .load(uri)
-                            .fitCenter()
-                            .into(object : SimpleTarget<Bitmap>() {
-                                override fun onResourceReady(
-                                    resource: Bitmap,
-                                    transition: Transition<in Bitmap>?
-                                ) {
-                                    bitmap = resource
-                                    imagePreview.setImageBitmap(resource)
-                                }
-                            })
+                        GlideApp.with(context)
+                                .asBitmap()
+                                .load(uri)
+                                .fitCenter()
+                                .into(object : ImageViewTarget<Bitmap>(imagePreview) {
+                                    override fun setResource(resource: Bitmap?) {
+                                        bitmap = resource
+                                        imagePreview.setImageBitmap(resource)
+                                    }
+                                })
                     }
                     imagePreview.isVisible = true
                 }

app/src/main/java/chat/rocket/android/chatroom/uimodel/UiModelMapper.kt

@@ -416,21 +416,18 @@ class UiModelMapper @Inject constructor(
         return fullUrl
     }
 
-    private fun attachmentText(text: String?, attachment: Attachment?, context: Context): String? {
-        return if (attachment != null) {
-            when {
-                attachment.imageUrl.isNotNullNorEmpty() -> context.getString(R.string.msg_preview_photo)
-                attachment.videoUrl.isNotNullNorEmpty() -> context.getString(R.string.msg_preview_video)
-                attachment.audioUrl.isNotNullNorEmpty() -> context.getString(R.string.msg_preview_audio)
-                attachment.titleLink.isNotNullNorEmpty() &&
-                        attachment.type?.contentEquals("file") == true ->
-                    context.getString(R.string.msg_preview_file)
-                else -> text
+    private fun attachmentText(text: String?, attachment: Attachment?, context: Context): String? = attachment?.run {
+            with(context) {
+                when {
+                    imageUrl.isNotNullNorEmpty() -> getString(R.string.msg_preview_photo)
+                    videoUrl.isNotNullNorEmpty() -> getString(R.string.msg_preview_video)
+                    audioUrl.isNotNullNorEmpty() -> getString(R.string.msg_preview_audio)
+                    titleLink.isNotNullNorEmpty() &&
+                            type?.contentEquals("file") == true -> getString(R.string.msg_preview_file)
+                    else -> text
+                }
             }
-        } else {
-            text
-        }
-    }
+        } ?: text
 
     private fun attachmentDescription(attachment: Attachment): String? {
         return attachment.description

app/src/main/java/chat/rocket/android/chatrooms/adapter/RoomViewHolder.kt

@@ -8,20 +8,23 @@ import androidx.core.view.isInvisible
 import androidx.core.view.isVisible
 import chat.rocket.android.R
 import chat.rocket.android.chatrooms.adapter.model.RoomUiModel
+import chat.rocket.android.util.extensions.setTextViewAppearance
 import chat.rocket.common.model.RoomType
 import chat.rocket.common.model.UserStatus
 import kotlinx.android.synthetic.main.item_chat.view.*
 import kotlinx.android.synthetic.main.unread_messages_badge.view.*
 
-class RoomViewHolder(itemView: View, private val listener: (RoomUiModel) -> Unit) :
-    ViewHolder<RoomItemHolder>(itemView) {
+class RoomViewHolder(
+        itemView: View,
+        private val listener: (RoomUiModel) -> Unit
+) : ViewHolder<RoomItemHolder>(itemView) {
     private val resources: Resources = itemView.resources
-    private val channelIcon: Drawable = resources.getDrawable(R.drawable.ic_hashtag_12dp)
-    private val groupIcon: Drawable = resources.getDrawable(R.drawable.ic_lock_12_dp)
-    private val onlineIcon: Drawable = resources.getDrawable(R.drawable.ic_status_online_12dp)
-    private val awayIcon: Drawable = resources.getDrawable(R.drawable.ic_status_away_12dp)
-    private val busyIcon: Drawable = resources.getDrawable(R.drawable.ic_status_busy_12dp)
-    private val offlineIcon: Drawable = resources.getDrawable(R.drawable.ic_status_invisible_12dp)
+    private val channelIcon: Drawable = resources.getDrawable(R.drawable.ic_hashtag_12dp, null)
+    private val groupIcon: Drawable = resources.getDrawable(R.drawable.ic_lock_12_dp, null)
+    private val onlineIcon: Drawable = resources.getDrawable(R.drawable.ic_status_online_12dp, null)
+    private val awayIcon: Drawable = resources.getDrawable(R.drawable.ic_status_away_12dp, null)
+    private val busyIcon: Drawable = resources.getDrawable(R.drawable.ic_status_busy_12dp, null)
+    private val offlineIcon: Drawable = resources.getDrawable(R.drawable.ic_status_invisible_12dp, null)
 
     override fun bindViews(data: RoomItemHolder) {
         val room = data.data
@@ -53,14 +56,14 @@ class RoomViewHolder(itemView: View, private val listener: (RoomUiModel) -> Unit
                 if (room.unread == null) text_total_unread_messages.text = "!"
                 if (room.unread != null) text_total_unread_messages.text = room.unread
                 if (room.mentions) text_total_unread_messages.text = "@${room.unread}"
-                text_chat_name.setTextAppearance(context, R.style.ChatList_ChatName_Unread_TextView)
-                text_timestamp.setTextAppearance(context, R.style.ChatList_Timestamp_Unread_TextView)
-                text_last_message.setTextAppearance(context, R.style.ChatList_LastMessage_Unread_TextView)
+                text_chat_name.setTextViewAppearance(context, R.style.ChatList_ChatName_Unread_TextView)
+                text_timestamp.setTextViewAppearance(context, R.style.ChatList_Timestamp_Unread_TextView)
+                text_last_message.setTextViewAppearance(context, R.style.ChatList_LastMessage_Unread_TextView)
                 text_total_unread_messages.isVisible = true
             } else {
-                text_chat_name.setTextAppearance(context, R.style.ChatList_ChatName_TextView)
-                text_timestamp.setTextAppearance(context, R.style.ChatList_Timestamp_TextView)
-                text_last_message.setTextAppearance(context, R.style.ChatList_LastMessage_TextView)
+                text_chat_name.setTextViewAppearance(context, R.style.ChatList_ChatName_TextView)
+                text_timestamp.setTextViewAppearance(context, R.style.ChatList_Timestamp_TextView)
+                text_last_message.setTextViewAppearance(context, R.style.ChatList_LastMessage_TextView)
                 text_total_unread_messages.isInvisible = true
             }
 

app/src/main/java/chat/rocket/android/chatrooms/adapter/RoomsAdapter.kt

@@ -6,8 +6,7 @@ import chat.rocket.android.R
 import chat.rocket.android.chatrooms.adapter.model.RoomUiModel
 import chat.rocket.android.util.extensions.inflate
 
-class RoomsAdapter(private val listener: (RoomUiModel) -> Unit) :
-    RecyclerView.Adapter<ViewHolder<*>>() {
+class RoomsAdapter(private val listener: (RoomUiModel) -> Unit) : RecyclerView.Adapter<ViewHolder<*>>() {
 
     init {
         setHasStableIds(true)

app/src/main/java/chat/rocket/android/chatrooms/ui/ChatRoomsFragment.kt

@@ -82,9 +82,8 @@ class ChatRoomsFragment : Fragment(), ChatRoomsView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
         setHasOptionsMenu(true)
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID)
             chatRoomId.ifNotNullNotEmpty { roomId ->
                 presenter.loadChatRoom(roomId)
                 chatRoomId = null
@@ -132,10 +131,10 @@ class ChatRoomsFragment : Fragment(), ChatRoomsView {
             recycler_view.adapter = adapter
 
             viewModel.getChatRooms().observe(viewLifecycleOwner, Observer { rooms ->
-                rooms?.let {
-                    Timber.d("Got items: $it")
-                    adapter.values = it
-                    if (rooms.isNotEmpty()) {
+                rooms?.let { items ->
+                    Timber.d("Got items: $items")
+                    adapter.values = items
+                    if (items.isNotEmpty()) {
                         text_no_data_to_display.isVisible = false
                     }
                 }

app/src/main/java/chat/rocket/android/createchannel/ui/CreateChannelFragment.kt

 package chat.rocket.android.createchannel.ui
 
 import android.os.Bundle
-import android.view.LayoutInflater
-import android.view.Menu
-import android.view.MenuItem
-import android.view.View
-import android.view.ViewGroup
+import android.view.*
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.view.ActionMode
 import androidx.core.view.isVisible
@@ -294,8 +290,8 @@ class CreateChannelFragment : Fragment(), CreateChannelView, ActionMode.Callback
 
     private fun addChip(chipText: String) {
         val chip = Chip(context)
-        chip.chipText = chipText
-        chip.isCloseIconEnabled = true
+        chip.text = chipText
+        chip.isCloseIconVisible = true
         chip.setChipBackgroundColorResource(R.color.icon_grey)
         setupChipOnCloseIconClickListener(chip)
         chip_group_member.addView(chip)
@@ -304,7 +300,7 @@ class CreateChannelFragment : Fragment(), CreateChannelView, ActionMode.Callback
     private fun setupChipOnCloseIconClickListener(chip: Chip) {
         chip.setOnCloseIconClickListener {
             removeChip(it)
-            removeMember((it as Chip).chipText.toString())
+            removeMember((it as Chip).text.toString())
             // whenever we remove a chip we should process the chip group visibility.
             processChipGroupVisibility()
         }

app/src/main/java/chat/rocket/android/db/DatabaseManager.kt

@@ -223,8 +223,8 @@ class DatabaseManager(val context: Application, val serverUrl: String) {
         val list = mutableListOf<BaseMessageEntity>()
         reactions.keys.forEach { reaction ->
             val users = reactions[reaction]
-            users?.let { users ->
-                list.add(ReactionEntity(reaction, message.id, users.size, users.joinToString()))
+            users?.let {
+                list.add(ReactionEntity(reaction, message.id, it.size, it.joinToString()))
             }
         }
 
@@ -375,15 +375,11 @@ class DatabaseManager(val context: Application, val serverUrl: String) {
         }
     }
 
-    private fun mapLastMessageText(message: Message?): String? {
-        return if (message == null) {
-            null
+    private fun mapLastMessageText(message: Message?): String? = message?.run {
+        if (this.message.isEmpty() && attachments?.isNotEmpty() == true) {
+            mapAttachmentText(attachments!![0])
         } else {
-            return if (message.message.isEmpty() && message.attachments?.isNotEmpty() == true) {
-                mapAttachmentText(message.attachments!![0])
-            } else {
-                message.message
-            }
+            this.message
         }
     }
 

app/src/main/java/chat/rocket/android/db/model/Attachments.kt

 package chat.rocket.android.db.model
 
 import android.content.Context
-import androidx.room.ColumnInfo
-import androidx.room.Entity
-import androidx.room.ForeignKey
-import androidx.room.Index
-import androidx.room.PrimaryKey
+import androidx.room.*
 import chat.rocket.android.R
 import chat.rocket.android.util.extension.orFalse
 import chat.rocket.android.util.extensions.isNotNullNorEmpty
@@ -114,8 +110,7 @@ fun Attachment.asEntity(msgId: String, context: Context): List<BaseMessageEntity
     val list = mutableListOf<BaseMessageEntity>()
 
     val text = mapAttachmentText(text, attachments?.firstOrNull(), context)
-
-    val entity = AttachmentEntity(
+    list.add(AttachmentEntity(
             _id = attachmentId,
             messageId = msgId,
             title = title,
@@ -144,16 +139,14 @@ fun Attachment.asEntity(msgId: String, context: Context): List<BaseMessageEntity
             buttonAlignment = buttonAlignment,
             hasActions = actions?.isNotEmpty() == true,
             hasFields = fields?.isNotEmpty() == true
-    )
-    list.add(entity)
+    ))
 
     fields?.forEach { field ->
-        val entity = AttachmentFieldEntity(
+        list.add(AttachmentFieldEntity(
                 attachmentId = attachmentId,
                 title = field.title,
                 value = field.value
-        )
-        list.add(entity)
+        ))
     }
 
     actions?.forEach { action ->
@@ -175,18 +168,16 @@ fun Attachment.asEntity(msgId: String, context: Context): List<BaseMessageEntity
     return list
 }
 
-fun mapAttachmentText(text: String?, attachment: Attachment?, context: Context): String? {
-    return if (attachment != null) {
+fun mapAttachmentText(text: String?, attachment: Attachment?, context: Context): String? = attachment?.run {
+    with(context) {
         when {
-            attachment.imageUrl.isNotNullNorEmpty() -> context.getString(R.string.msg_preview_photo)
-            attachment.videoUrl.isNotNullNorEmpty() -> context.getString(R.string.msg_preview_video)
-            attachment.audioUrl.isNotNullNorEmpty() -> context.getString(R.string.msg_preview_audio)
-            attachment.titleLink.isNotNullNorEmpty() &&
-                    attachment.type?.contentEquals("file") == true ->
-                context.getString(R.string.msg_preview_file)
+            imageUrl.isNotNullNorEmpty() -> getString(R.string.msg_preview_photo)
+            videoUrl.isNotNullNorEmpty() -> getString(R.string.msg_preview_video)
+            audioUrl.isNotNullNorEmpty() -> getString(R.string.msg_preview_audio)
+            titleLink.isNotNullNorEmpty() &&
+                    type?.contentEquals("file") == true ->
+                getString(R.string.msg_preview_file)
             else -> text
         }
-    } else {
-        text
-    }
+    } ?: text
 }

app/src/main/java/chat/rocket/android/favoritemessages/ui/FavoriteMessagesFragment.kt

@@ -48,12 +48,9 @@ class FavoriteMessagesFragment : Fragment(), FavoriteMessagesView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(INTENT_CHAT_ROOM_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            chatRoomId = getString(INTENT_CHAT_ROOM_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/files/ui/FilesFragment.kt

@@ -55,12 +55,9 @@ class FilesFragment : Fragment(), FilesView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/helper/ImageHelper.kt

@@ -51,10 +51,10 @@ object ImageHelper {
             ViewGroup.LayoutParams.MATCH_PARENT,
             ViewGroup.LayoutParams.WRAP_CONTENT
         )
-        val toolbar = Toolbar(context).also {
-            it.inflateMenu(R.menu.image_actions)
-            it.setOnMenuItemClickListener {
-                return@setOnMenuItemClickListener when (it.itemId) {
+        val toolbar = Toolbar(context).also { toolbar ->
+            toolbar.inflateMenu(R.menu.image_actions)
+            toolbar.setOnMenuItemClickListener { view ->
+                return@setOnMenuItemClickListener when (view.itemId) {
                     R.id.action_save_image -> saveImage(context)
                     else -> true
                 }
@@ -62,14 +62,16 @@ object ImageHelper {
 
             val titleSize = context.resources
                 .getDimensionPixelSize(R.dimen.viewer_toolbar_title)
-            val titleTextView = TextView(context).also {
-                it.text = imageName
-                it.setTextColor(Color.WHITE)
-                it.setTextSize(TypedValue.COMPLEX_UNIT_PX, titleSize.toFloat())
-                it.ellipsize = TextUtils.TruncateAt.END
-                it.setSingleLine()
-                it.typeface = Typeface.DEFAULT_BOLD
-                it.setPadding(pad)
+            val titleTextView = TextView(context).also { tv ->
+                with(tv) {
+                    text = imageName
+                    setTextColor(Color.WHITE)
+                    setTextSize(TypedValue.COMPLEX_UNIT_PX, titleSize.toFloat())
+                    ellipsize = TextUtils.TruncateAt.END
+                    setSingleLine()
+                    typeface = Typeface.DEFAULT_BOLD
+                    setPadding(pad)
+                }
             }
 
             val backArrowView = ImageView(context).also {
@@ -83,8 +85,8 @@ object ImageHelper {
                 AppBarLayout.LayoutParams.WRAP_CONTENT
             )
 
-            it.addView(backArrowView, layoutParams)
-            it.addView(titleTextView, layoutParams)
+            toolbar.addView(backArrowView, layoutParams)
+            toolbar.addView(titleTextView, layoutParams)
         }
 
         val appBarLayout = AppBarLayout(context).also {

app/src/main/java/chat/rocket/android/members/adapter/MembersAdapter.kt

@@ -10,8 +10,9 @@ import chat.rocket.android.util.extensions.inflate
 import kotlinx.android.synthetic.main.avatar.view.*
 import kotlinx.android.synthetic.main.item_member.view.*
 
-class MembersAdapter(private val listener: (MemberUiModel) -> Unit) :
-    RecyclerView.Adapter<MembersAdapter.ViewHolder>() {
+class MembersAdapter(
+        private val listener: (MemberUiModel) -> Unit
+) : RecyclerView.Adapter<MembersAdapter.ViewHolder>() {
     private var dataSet: List<MemberUiModel> = ArrayList()
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MembersAdapter.ViewHolder =
@@ -43,7 +44,8 @@ class MembersAdapter(private val listener: (MemberUiModel) -> Unit) :
         fun bind(memberUiModel: MemberUiModel, listener: (MemberUiModel) -> Unit) = with(itemView) {
             image_avatar.setImageURI(memberUiModel.avatarUri)
             text_member.content = memberUiModel.displayName
-            text_member.setCompoundDrawablesRelativeWithIntrinsicBounds(DrawableHelper.getUserStatusDrawable(memberUiModel.status, context), null, null, null)
+            text_member.setCompoundDrawablesRelativeWithIntrinsicBounds(
+                    DrawableHelper.getUserStatusDrawable(memberUiModel.status, context), null, null, null)
             setOnClickListener { listener(memberUiModel) }
         }
     }

app/src/main/java/chat/rocket/android/members/ui/MembersFragment.kt

@@ -52,12 +52,9 @@ class MembersFragment : Fragment(), MembersView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(
@@ -80,7 +77,7 @@ class MembersFragment : Fragment(), MembersView {
             setupToolbar(total)
             if (adapter.itemCount == 0) {
                 adapter.prependData(dataSet)
-                if (dataSet.size >= 59) { // TODO Check why the API retorns the specified count -1
+                if (dataSet.size >= 59) { // TODO Check why the API returns the specified count -1
                     recycler_view.addOnScrollListener(object :
                         EndlessRecyclerViewScrollListener(linearLayoutManager) {
                         override fun onLoadMore(

app/src/main/java/chat/rocket/android/mentions/ui/MentionsFragment.kt

@@ -48,12 +48,9 @@ class MentionsFragment : Fragment(), MentionsView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/pinnedmessages/ui/PinnedMessagesFragment.kt

@@ -48,12 +48,9 @@ class PinnedMessagesFragment : Fragment(), PinnedMessagesView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            chatRoomId = bundle.getString(BUNDLE_CHAT_ROOM_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            chatRoomId = getString(BUNDLE_CHAT_ROOM_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/profile/ui/ProfileFragment.kt

@@ -96,9 +96,13 @@ class ProfileFragment : Fragment(), ProfileView, ActionMode.Callback {
     override fun onActivityResult(requestCode: Int, resultCode: Int, resultData: Intent?) {
         if (resultData != null && resultCode == Activity.RESULT_OK) {
             if (requestCode == REQUEST_CODE_FOR_PERFORM_SAF) {
-                presenter.updateAvatar(resultData.data)
+                resultData.data?.let {
+                    presenter.updateAvatar(it)
+                }
             } else if (requestCode == REQUEST_CODE_FOR_PERFORM_CAMERA) {
-                presenter.preparePhotoAndUpdateAvatar(resultData.extras["data"] as Bitmap)
+                resultData.extras?.get("data")?.let {
+                    presenter.preparePhotoAndUpdateAvatar(it as Bitmap)
+                }
             }
         }
     }

app/src/main/java/chat/rocket/android/push/PushManager.kt

@@ -186,7 +186,7 @@ class PushManager @Inject constructor(
                 .setGroupSummary(false)
 
             if (style == null || "inbox" == style) {
-                val pushMessageList = groupedPushes.hostToPushMessageList.get(host)
+                val pushMessageList = groupedPushes.hostToPushMessageList[host]
 
                 if (pushMessageList != null) {
                     val userMessages = pushMessageList.filter {
@@ -230,7 +230,10 @@ class PushManager @Inject constructor(
     }
 
     @RequiresApi(Build.VERSION_CODES.O)
-    private fun createBaseNotificationBuilder(pushMessage: PushMessage, grouped: Boolean = false): NotificationCompat.Builder {
+    private fun createBaseNotificationBuilder(
+            pushMessage: PushMessage,
+            grouped: Boolean = false
+    ): NotificationCompat.Builder {
         return with(pushMessage) {
             val id = notificationId.toInt()
             val host = info.host
@@ -295,7 +298,12 @@ class PushManager @Inject constructor(
         return PendingIntent.getBroadcast(context, pushMessage.notificationId.toInt(), deleteIntent, PendingIntent.FLAG_UPDATE_CURRENT)
     }
 
-    private fun getContentIntent(context: Context, notificationId: Int, pushMessage: PushMessage, grouped: Boolean = false): PendingIntent {
+    private fun getContentIntent(
+            context: Context,
+            notificationId: Int,
+            pushMessage: PushMessage,
+            grouped: Boolean = false
+    ): PendingIntent {
         val roomId = if (!grouped) pushMessage.info.roomId else null
         val notificationIntent = context.changeServerIntent(pushMessage.info.host, chatRoomId = roomId)
         return PendingIntent.getActivity(context, random.nextInt(), notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT)
@@ -303,7 +311,11 @@ class PushManager @Inject constructor(
 
     // CharSequence extensions
     private fun CharSequence.fromHtml(): Spanned {
-        return Html.fromHtml(this as String)
+        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
+            Html.fromHtml(this as String, Html.FROM_HTML_MODE_LEGACY)
+        } else {
+            Html.fromHtml(this as String)
+        }
     }
 
     // NotificationCompat.Builder extensions
@@ -383,12 +395,12 @@ data class PushMessage(
 ) : Parcelable {
 
     constructor(parcel: Parcel) : this(
+        parcel.readString()!!,
+        parcel.readString()!!,
+        parcel.readParcelable(PushMessage::class.java.classLoader)!!,
         parcel.readString(),
         parcel.readString(),
-        parcel.readParcelable(PushMessage::class.java.classLoader),
-        parcel.readString(),
-        parcel.readString(),
-        parcel.readString(),
+        parcel.readString()!!,
         parcel.readString(),
         parcel.readString())
 
@@ -433,9 +445,9 @@ data class PushInfo @KotshiConstructor constructor(
     }
 
     constructor(parcel: Parcel) : this(
-        parcel.readString(),
-        parcel.readString(),
-        roomTypeOf(parcel.readString()),
+        parcel.readString()!!,
+        parcel.readString()!!,
+        roomTypeOf(parcel.readString()!!),
         parcel.readString(),
         parcel.readParcelable(PushInfo::class.java.classLoader))
 
@@ -481,7 +493,7 @@ data class PushSender @KotshiConstructor constructor(
     val name: String?
 ) : Parcelable {
     constructor(parcel: Parcel) : this(
-        parcel.readString(),
+        parcel.readString()!!,
         parcel.readString(),
         parcel.readString())
 

app/src/main/java/chat/rocket/android/server/infraestructure/ConnectionManager.kt

@@ -97,8 +97,8 @@ class ConnectionManager(
 
                         resubscribeRooms()
 
-                        temporaryStatus?.let { status ->
-                            client.setTemporaryStatus(status)
+                        temporaryStatus?.let { tempStatus ->
+                            client.setTemporaryStatus(tempStatus)
                         }
                     }
                     is State.Waiting -> {
@@ -231,7 +231,7 @@ class ConnectionManager(
     }
 
     private fun resubscribeRooms() {
-        roomMessagesChannels.toList().map { (roomId, channel) ->
+        roomMessagesChannels.toList().map { (roomId, _) ->
             client.subscribeRoomMessages(roomId) { _, id ->
                 Timber.d("Subscribed to $roomId: $id")
                 subscriptionIdMap[roomId] = id

app/src/main/java/chat/rocket/android/server/infraestructure/DatabaseMessageMapper.kt

@@ -153,7 +153,7 @@ class DatabaseMessageMapper(private val dbManager: DatabaseManager) {
                     null
                 }
 
-                val attachment = Attachment(
+                list.add(Attachment(
                         title = title,
                         type = type,
                         description = description,
@@ -179,10 +179,10 @@ class DatabaseMessageMapper(private val dbManager: DatabaseManager) {
                         authorLink = authorLink,
                         fields = fields,
                         fallback = fallback,
-                        buttonAlignment = if (actions != null && actions.isNotEmpty()) buttonAlignment ?: "vertical" else null,
+                        buttonAlignment = if (actions != null && actions.isNotEmpty()) buttonAlignment
+                                ?: "vertical" else null,
                         actions = actions
-                )
-                list.add(attachment)
+                ))
             }
         }
         return list

app/src/main/java/chat/rocket/android/server/infraestructure/DatabaseMessagesRepository.kt

@@ -46,8 +46,8 @@ class DatabaseMessagesRepository(
         dbManager.processMessagesBatch(listOf(message)).join()
     }
 
-    override suspend fun saveAll(messages: List<Message>) {
-        dbManager.processMessagesBatch(messages).join()
+    override suspend fun saveAll(newMessages: List<Message>) {
+        dbManager.processMessagesBatch(newMessages).join()
     }
 
     override suspend fun removeById(id: String) {
@@ -78,7 +78,7 @@ class DatabaseMessagesRepository(
 
     override suspend fun getLastSyncDate(roomId: String): Long? = withContext(CommonPool) {
         retryDB("getLastSync($roomId)") {
-            dbManager.messageDao().getLastSync(roomId)?.let { it.timestamp }
+            dbManager.messageDao().getLastSync(roomId)?.timestamp
         }
     }
 }
\ No newline at end of file

app/src/main/java/chat/rocket/android/server/infraestructure/SharedPreferencesAccountsRepository.kt

@@ -14,12 +14,12 @@ class SharedPreferencesAccountsRepository(
     private val moshi: Moshi
 ) : AccountsRepository {
 
-    override fun save(newAccount: Account) {
+    override fun save(account: Account) {
         val accounts = load()
 
-        val newList = accounts.filter { account -> newAccount.serverUrl != account.serverUrl }
+        val newList = accounts.filter { account -> account.serverUrl != account.serverUrl }
             .toMutableList()
-        newList.add(0, newAccount)
+        newList.add(0, account)
         save(newList)
     }
 
@@ -28,7 +28,7 @@ class SharedPreferencesAccountsRepository(
         val type = Types.newParameterizedType(List::class.java, Account::class.java)
         val adapter = moshi.adapter<List<Account>>(type)
 
-        return adapter.fromJson(json) ?: emptyList()
+        return if (json == null) emptyList() else adapter.fromJson(json) ?: emptyList()
     }
 
     override fun remove(serverUrl: String) {

app/src/main/java/chat/rocket/android/server/infraestructure/SharedPrefsBasicAuthRepository.kt

@@ -15,8 +15,7 @@ class SharedPrefsBasicAuthRepository(
 ) : BasicAuthRepository {
 
     override fun save(basicAuth: BasicAuth) {
-        val newList = load().filter { basicAuth -> basicAuth.host != basicAuth.host }
-            .toMutableList()
+        val newList = load().filter { item -> item.host != item.host }.toMutableList()
         newList.add(0, basicAuth)
         save(newList)
     }
@@ -26,7 +25,7 @@ class SharedPrefsBasicAuthRepository(
         val type = Types.newParameterizedType(List::class.java, BasicAuth::class.java)
         val adapter = moshi.adapter<List<BasicAuth>>(type)
 
-        return adapter.fromJson(json) ?: emptyList()
+        return if (json == null) emptyList() else adapter.fromJson(json) ?: emptyList()
     }
 
     private fun save(basicAuths: List<BasicAuth>) {

app/src/main/java/chat/rocket/android/server/presentation/ChangeServerPresenter.kt

@@ -51,6 +51,7 @@ class ChangeServerPresenter @Inject constructor(
                 val settings = settingsRepository.get(serverUrl)
                 if (settings == null) {
                     // TODO - reload settings...
+                    // settingsRepository returns non nullable settings
                 }
 
                 // Call disconnect on the old url if any...

app/src/main/java/chat/rocket/android/userdetails/ui/UserDetailsFragment.kt

@@ -52,12 +52,9 @@ class UserDetailsFragment : Fragment(), UserDetailsView {
         super.onCreate(savedInstanceState)
         AndroidSupportInjection.inject(this)
 
-        val bundle = arguments
-        if (bundle != null) {
-            userId = bundle.getString(BUNDLE_USER_ID)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            userId = getString(BUNDLE_USER_ID, "")
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(

app/src/main/java/chat/rocket/android/util/HttpLoggingInterceptor.kt

@@ -193,7 +193,7 @@ class HttpLoggingInterceptor constructor(private val logger: Logger) : Intercept
 
         val responseBody = response.body()
         val contentLength = responseBody!!.contentLength()
-        val bodySize = if (contentLength != -1L) contentLength.toString() + "-byte" else "unknown-length"
+        val bodySize = if (contentLength != -1L) "$contentLength-byte" else "unknown-length"
         val responseStr = if (response.message().isEmpty()) "" else " ${response.message()}"
         logger.log("<-- ${response.code()}$responseStr ${response.request().url()}"
                 + " (" + tookMs + "ms" + (if (!logHeaders) ", $bodySize body" else "") + ')'.toString())

app/src/main/java/chat/rocket/android/util/extensions/String.kt

@@ -69,11 +69,8 @@ fun String.userId(userId: String?): String? {
     return userId?.let { this.replace(it, "") }
 }
 
-fun String.lowercaseUrl(): String? {
-    val httpUrl = HttpUrl.parse(this)
-    val newScheme = httpUrl?.scheme()?.toLowerCase()
-
-    return httpUrl?.newBuilder()?.scheme(newScheme)?.build()?.toString()
+fun String.lowercaseUrl(): String? = HttpUrl.parse(this)?.run {
+    newBuilder().scheme(scheme().toLowerCase()).build().toString()
 }
 
 fun String?.isNotNullNorEmpty(): Boolean = this != null && this.isNotEmpty()

app/src/main/java/chat/rocket/android/util/extensions/TextView.kt

+package chat.rocket.android.util.extensions
+
+import android.content.Context
+import android.os.Build
+import android.widget.TextView
+
+fun TextView.setTextViewAppearance(context: Context, style: Int) {
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+        setTextAppearance(style)
+    } else {
+        setTextAppearance(context, style)
+    }
+}
\ No newline at end of file

app/src/main/java/chat/rocket/android/webview/adminpanel/ui/AdminPanelWebViewFragment.kt

@@ -27,13 +27,11 @@ class AdminPanelWebViewFragment : DaggerFragment() {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        val bundle = arguments
-        if (bundle != null) {
-            webPageUrl = bundle.getString(BUNDLE_WEB_PAGE_URL)
-            userToken = bundle.getString(BUNDLE_USER_TOKEN)
-        } else {
-            requireNotNull(bundle) { "no arguments supplied when the fragment was instantiated" }
-        }
+        arguments?.run {
+            webPageUrl = getString(BUNDLE_WEB_PAGE_URL, "")
+            userToken = getString(BUNDLE_USER_TOKEN, "")
+
+        } ?: requireNotNull(arguments) { "no arguments supplied when the fragment was instantiated" }
     }
 
     override fun onCreateView(
@@ -65,7 +63,7 @@ class AdminPanelWebViewFragment : DaggerFragment() {
         web_view.webViewClient = object : WebViewClient() {
             override fun onPageFinished(view: WebView, url: String) {
                 super.onPageFinished(view, url)
-                ui { _ ->
+                ui {
                     view_loading.hide()
                     web_view.evaluateJavascript("Meteor.loginWithToken('$userToken', function() { })") {}
                 }

app/src/main/java/chat/rocket/android/widget/DividerItemDecoration.kt

@@ -14,7 +14,7 @@ import androidx.recyclerview.widget.RecyclerView
  * @see RecyclerView.ItemDecoration
  */
 class DividerItemDecoration() : RecyclerView.ItemDecoration() {
-    private lateinit var divider: Drawable
+    private var divider: Drawable? = null
     private var boundStart = 0
     private var boundEnd = 0
 
@@ -59,10 +59,10 @@ class DividerItemDecoration() : RecyclerView.ItemDecoration() {
             val params = child.layoutParams as RecyclerView.LayoutParams
 
             val top = child.bottom + params.bottomMargin
-            val bottom = top + divider.intrinsicHeight
+            val bottom = top + (divider?.intrinsicHeight ?: 0)
 
-            divider.setBounds(left, top, right, bottom)
-            divider.draw(c)
+            divider?.setBounds(left, top, right, bottom)
+            divider?.draw(c)
         }
     }