diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/activity/AccountSelectorActivity.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/activity/AccountSelectorActivity.kt
index e073ed083..cb2c44b5e 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/activity/AccountSelectorActivity.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/activity/AccountSelectorActivity.kt
@@ -42,7 +42,7 @@ import org.mariotaku.twidere.model.util.AccountUtils
 
 class AccountSelectorActivity : BaseActivity(), OnClickListener, OnItemClickListener {
 
-    private var adapter: AccountDetailsAdapter? = null
+    private lateinit var adapter: AccountDetailsAdapter
 
     private var firstCreated: Boolean = false
 
@@ -136,7 +136,6 @@ class AccountSelectorActivity : BaseActivity(), OnClickListener, OnItemClickList
     }
 
     fun selectSingleAccount(position: Int) {
-        val adapter = adapter!!
         val account = adapter.getItem(position)
         val data = Intent()
         data.putExtra(EXTRA_ID, account.key.id)
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsActivitiesFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsActivitiesFragment.kt
index 112710ead..9af4c9bf3 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsActivitiesFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsActivitiesFragment.kt
@@ -217,14 +217,10 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
     }
 
     protected fun saveReadPosition() {
-        val layoutManager = layoutManager
-        if (layoutManager != null) {
-            saveReadPosition(layoutManager.findFirstVisibleItemPosition())
-        }
+        saveReadPosition(layoutManager.findFirstVisibleItemPosition())
     }
 
     override fun onLoadFinished(loader: Loader<List<ParcelableActivity>>, data: List<ParcelableActivity>) {
-        val adapter = adapter
         val rememberPosition = preferences.getBoolean(KEY_REMEMBER_POSITION, false)
         val readFromBottom = preferences.getBoolean(KEY_READ_FROM_BOTTOM, false)
         var lastReadId: Long
@@ -315,7 +311,6 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
     }
 
     override fun onMediaClick(holder: IStatusViewHolder, view: View, media: ParcelableMedia, position: Int) {
-        val adapter = adapter
         val status = adapter.getActivity(position)?.getActivityStatus() ?: return
         IntentUtils.openMedia(activity, status, media, null, preferences.getBoolean(KEY_NEW_DOCUMENT_API))
         // BEGIN HotMobi
@@ -435,7 +430,6 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
         scrollListener!!.reversed = preferences.getBoolean(KEY_READ_FROM_BOTTOM)
-        val adapter = adapter
         val layoutManager = layoutManager
         adapter.setListener(this)
         registerForContextMenu(recyclerView)
@@ -452,7 +446,6 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
     override val reachingEnd: Boolean
         get() {
             val lm = layoutManager
-            val adapter = adapter
             val lastPosition = lm.findLastCompletelyVisibleItemPosition()
             val itemCount = adapter.itemCount
             var finalPos = itemCount - 1
@@ -520,7 +513,6 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
 
     override fun onCreateContextMenu(menu: ContextMenu, v: View, menuInfo: ContextMenu.ContextMenuInfo?) {
         if (!userVisibleHint || menuInfo == null) return
-        val adapter = adapter
         val inflater = MenuInflater(context)
         val contextMenuInfo = menuInfo as ExtendedRecyclerView.ContextMenuInfo?
         val position = contextMenuInfo!!.position
@@ -534,10 +526,9 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
         }
     }
 
-    override fun onContextItemSelected(item: MenuItem?): Boolean {
+    override fun onContextItemSelected(item: MenuItem): Boolean {
         if (!userVisibleHint) return false
-        val adapter = adapter
-        val contextMenuInfo = item!!.menuInfo as ExtendedRecyclerView.ContextMenuInfo
+        val contextMenuInfo = item.menuInfo as ExtendedRecyclerView.ContextMenuInfo
         val position = contextMenuInfo.position
 
         when (adapter.getItemViewType(position)) {
@@ -559,7 +550,6 @@ abstract class AbsActivitiesFragment protected constructor() : AbsContentListRec
 
     override fun createItemDecoration(context: Context, recyclerView: RecyclerView,
                                       layoutManager: LinearLayoutManager): RecyclerView.ItemDecoration? {
-        val adapter = adapter
         val itemDecoration = object : DividerItemDecoration(context,
                 (recyclerView.layoutManager as LinearLayoutManager).orientation) {
             override fun isDividerEnabled(childPos: Int): Boolean {
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsContentListViewFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsContentListViewFragment.kt
index 254f270bf..be1154402 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsContentListViewFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsContentListViewFragment.kt
@@ -42,12 +42,12 @@ import org.mariotaku.twidere.util.TwidereColorUtils
  * Created by mariotaku on 15/4/16.
  */
 abstract class AbsContentListViewFragment<A : ListAdapter> : BaseSupportFragment(), OnRefreshListener, RefreshScrollTopInterface, ControlBarOffsetListener, ContentListSupport, AbsListView.OnScrollListener {
-    private var scrollHandler: ListViewScrollHandler? = null
+    private lateinit var scrollHandler: ListViewScrollHandler
 
-    override var adapter: A? = null
+    override lateinit var adapter: A
 
     // Data fields
-    private val mSystemWindowsInsets = Rect()
+    private val systemWindowsInsets = Rect()
 
     override fun onControlBarOffsetChanged(activity: IControlBarActivity, offset: Float) {
         updateRefreshProgressOffset()
@@ -128,9 +128,10 @@ abstract class AbsContentListViewFragment<A : ListAdapter> : BaseSupportFragment
         }
         listView.adapter = adapter
         listView.clipToPadding = false
-        scrollHandler = ListViewScrollHandler(this, ListViewScrollHandler.ListViewCallback(listView))
-        scrollHandler!!.touchSlop = ViewConfiguration.get(context).scaledTouchSlop
-        scrollHandler!!.onScrollListener = this
+        scrollHandler = ListViewScrollHandler(this, ListViewScrollHandler.ListViewCallback(listView)).apply {
+            this.touchSlop = ViewConfiguration.get(context).scaledTouchSlop
+            this.onScrollListener = this@AbsContentListViewFragment
+        }
     }
 
 
@@ -148,7 +149,7 @@ abstract class AbsContentListViewFragment<A : ListAdapter> : BaseSupportFragment
         listView.setPadding(insets.left, insets.top, insets.right, insets.bottom)
         errorContainer.setPadding(insets.left, insets.top, insets.right, insets.bottom)
         progressContainer.setPadding(insets.left, insets.top, insets.right, insets.bottom)
-        mSystemWindowsInsets.set(insets)
+        systemWindowsInsets.set(insets)
         updateRefreshProgressOffset()
     }
 
@@ -192,14 +193,14 @@ abstract class AbsContentListViewFragment<A : ListAdapter> : BaseSupportFragment
 
     protected fun updateRefreshProgressOffset() {
         val activity = activity
-        if (activity !is IControlBarActivity || mSystemWindowsInsets.top == 0 || swipeLayout == null
+        if (activity !is IControlBarActivity || systemWindowsInsets.top == 0 || swipeLayout == null
                 || refreshing) {
             return
         }
         val density = resources.displayMetrics.density
         val progressCircleDiameter = swipeLayout.progressCircleDiameter
         val controlBarOffsetPixels = Math.round(activity.controlBarHeight * (1 - activity.controlBarOffset))
-        val swipeStart = mSystemWindowsInsets.top - controlBarOffsetPixels - progressCircleDiameter
+        val swipeStart = systemWindowsInsets.top - controlBarOffsetPixels - progressCircleDiameter
         // 64: SwipeRefreshLayout.DEFAULT_CIRCLE_TARGET
         val swipeDistance = Math.round(64 * density)
         swipeLayout.setProgressViewOffset(false, swipeStart, swipeStart + swipeDistance)
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsStatusesFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsStatusesFragment.kt
index 614cd735d..2f6799615 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsStatusesFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/AbsStatusesFragment.kt
@@ -170,7 +170,6 @@ abstract class AbsStatusesFragment protected constructor() :
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
         scrollListener?.reversed = preferences.getBoolean(SharedPreferenceConstants.KEY_READ_FROM_BOTTOM)
-        val adapter = adapter
         adapter.statusClickListener = this
         registerForContextMenu(recyclerView)
         navigationHelper = RecyclerViewNavigationHelper(recyclerView, layoutManager, adapter, this)
@@ -223,7 +222,6 @@ abstract class AbsStatusesFragment protected constructor() :
     }
 
     override fun onDestroy() {
-        val adapter = adapter
         adapter.statusClickListener = null
         super.onDestroy()
     }
@@ -316,7 +314,6 @@ abstract class AbsStatusesFragment protected constructor() :
     }
 
     override fun onLoadFinished(loader: Loader<List<ParcelableStatus>?>, data: List<ParcelableStatus>?) {
-        val adapter = adapter
         val rememberPosition = preferences.getBoolean(SharedPreferenceConstants.KEY_REMEMBER_POSITION, false)
         val readFromBottom = preferences.getBoolean(SharedPreferenceConstants.KEY_READ_FROM_BOTTOM, false)
         var lastReadPositionKey: Long
@@ -410,7 +407,6 @@ abstract class AbsStatusesFragment protected constructor() :
     }
 
     override fun onMediaClick(holder: IStatusViewHolder, view: View, media: ParcelableMedia, statusPosition: Int) {
-        val adapter = adapter
         val status = adapter.getStatus(statusPosition) ?: return
         IntentUtils.openMedia(activity, status, media, null,
                 preferences.getBoolean(SharedPreferenceConstants.KEY_NEW_DOCUMENT_API))
@@ -422,16 +418,12 @@ abstract class AbsStatusesFragment protected constructor() :
     }
 
     override fun onItemActionClick(holder: RecyclerView.ViewHolder, id: Int, position: Int) {
-        val context = context ?: return
-        val adapter = adapter
         val status = adapter.getStatus(position) ?: return
         handleStatusActionClick(context, fragmentManager, twitterWrapper, holder as StatusViewHolder, status, id)
     }
 
     override fun createItemDecoration(context: Context, recyclerView: RecyclerView, layoutManager: LinearLayoutManager): RecyclerView.ItemDecoration? {
-        val adapter = adapter
-        val itemDecoration = DividerItemDecoration(context,
-                (recyclerView.layoutManager as LinearLayoutManager).orientation)
+        val itemDecoration = DividerItemDecoration(context, (recyclerView.layoutManager as LinearLayoutManager).orientation)
         val res = context.resources
         if (adapter.profileImageEnabled) {
             val decorPaddingLeft = res.getDimensionPixelSize(R.dimen.element_spacing_normal) * 2 + res.getDimensionPixelSize(R.dimen.icon_size_status_profile_image)
@@ -511,7 +503,6 @@ abstract class AbsStatusesFragment protected constructor() :
     protected fun saveReadPosition(position: Int) {
         if (host == null) return
         if (position == RecyclerView.NO_POSITION) return
-        val adapter = adapter
         val status = adapter.getStatus(position) ?: return
         val positionKey = if (status.position_key > 0) status.position_key else status.timestamp
         readPositionTagWithArguments?.let {
@@ -534,7 +525,6 @@ abstract class AbsStatusesFragment protected constructor() :
 
     override fun onCreateContextMenu(menu: ContextMenu, v: View, menuInfo: ContextMenu.ContextMenuInfo?) {
         if (!userVisibleHint || menuInfo == null) return
-        val adapter = adapter
         val inflater = MenuInflater(context)
         val contextMenuInfo = menuInfo as ExtendedRecyclerView.ContextMenuInfo?
         val status = adapter.getStatus(contextMenuInfo!!.position)
@@ -542,9 +532,9 @@ abstract class AbsStatusesFragment protected constructor() :
         MenuUtils.setupForStatus(context, preferences, menu, status!!, twitterWrapper)
     }
 
-    override fun onContextItemSelected(item: MenuItem?): Boolean {
+    override fun onContextItemSelected(item: MenuItem): Boolean {
         if (!userVisibleHint) return false
-        val contextMenuInfo = item!!.menuInfo as ExtendedRecyclerView.ContextMenuInfo
+        val contextMenuInfo = item.menuInfo as ExtendedRecyclerView.ContextMenuInfo
         val status = adapter.getStatus(contextMenuInfo.position) ?: return false
         if (item.itemId == R.id.share) {
             val shareIntent = Utils.createStatusShareIntent(activity, status)
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/BaseFiltersFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/BaseFiltersFragment.kt
index 4557ede68..30d82452a 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/BaseFiltersFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/BaseFiltersFragment.kt
@@ -169,7 +169,6 @@ abstract class BaseFiltersFragment : AbsContentListViewFragment<SimpleCursorAdap
     }
 
     override fun onLoadFinished(loader: Loader<Cursor?>, data: Cursor?) {
-        val adapter = adapter
         adapter!!.swapCursor(data)
         if (data != null && data.count > 0) {
             showContent()
@@ -179,7 +178,6 @@ abstract class BaseFiltersFragment : AbsContentListViewFragment<SimpleCursorAdap
     }
 
     override fun onLoaderReset(loader: Loader<Cursor?>) {
-        val adapter = adapter
         adapter!!.swapCursor(null)
     }
 
@@ -254,15 +252,15 @@ abstract class BaseFiltersFragment : AbsContentListViewFragment<SimpleCursorAdap
                 val autoCompleteType: Int
                 autoCompleteType = args.getInt(EXTRA_AUTO_COMPLETE_TYPE, 0)
                 if (autoCompleteType != 0) {
-                    val mUserAutoCompleteAdapter: SimpleCursorAdapter
+                    val userAutoCompleteAdapter: SimpleCursorAdapter
                     if (autoCompleteType == AUTO_COMPLETE_TYPE_SOURCES) {
-                        mUserAutoCompleteAdapter = SourceAutoCompleteAdapter(activity)
+                        userAutoCompleteAdapter = SourceAutoCompleteAdapter(activity)
                     } else {
                         val adapter = ComposeAutoCompleteAdapter(activity)
                         adapter.accountKey = Utils.getDefaultAccountKey(activity)
-                        mUserAutoCompleteAdapter = adapter
+                        userAutoCompleteAdapter = adapter
                     }
-                    editText.setAdapter(mUserAutoCompleteAdapter)
+                    editText.setAdapter(userAutoCompleteAdapter)
                     editText.threshold = 1
                 }
             }
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorActivitiesFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorActivitiesFragment.kt
index e87a50930..42ddfeed3 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorActivitiesFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorActivitiesFragment.kt
@@ -55,7 +55,6 @@ abstract class CursorActivitiesFragment : AbsActivitiesFragment() {
 
     override fun onLoadingFinished() {
         val accountKeys = accountKeys
-        val adapter = adapter
         if (adapter.itemCount > 0) {
             showContent()
         } else if (accountKeys.isNotEmpty()) {
@@ -100,7 +99,6 @@ abstract class CursorActivitiesFragment : AbsActivitiesFragment() {
         }
         val expression = processWhere(where, accountSelectionArgs)
         val selection = expression.sql
-        val adapter = adapter
         adapter.showAccountsColor = accountKeys.size > 1
         val projection = Activities.COLUMNS
         return CursorActivitiesLoader(context, uri, projection, selection, expression.parameters,
@@ -258,7 +256,6 @@ abstract class CursorActivitiesFragment : AbsActivitiesFragment() {
     fun replaceStatusStates(result: ParcelableStatus?) {
         if (result == null) return
         val lm = layoutManager
-        val adapter = adapter
         val rangeStart = Math.max(adapter.activityStartIndex, lm.findFirstVisibleItemPosition())
         val rangeEnd = Math.min(lm.findLastVisibleItemPosition(), adapter.activityStartIndex + adapter.activityCount - 1)
         loop@ for (i in rangeStart..rangeEnd) {
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorStatusesFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorStatusesFragment.kt
index eeea4ccdb..b1acd9a0b 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorStatusesFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CursorStatusesFragment.kt
@@ -27,14 +27,12 @@ import android.net.Uri
 import android.os.Bundle
 import android.os.Handler
 import android.support.v4.content.Loader
-import android.util.Log
 import com.squareup.otto.Subscribe
 import kotlinx.android.synthetic.main.fragment_content_recyclerview.*
 import org.mariotaku.sqliteqb.library.ArgsArray
 import org.mariotaku.sqliteqb.library.Columns.Column
 import org.mariotaku.sqliteqb.library.Expression
 import org.mariotaku.twidere.R
-import org.mariotaku.twidere.TwidereConstants.LOGTAG
 import org.mariotaku.twidere.adapter.ListParcelableStatusesAdapter
 import org.mariotaku.twidere.adapter.iface.ILoadMoreSupportAdapter
 import org.mariotaku.twidere.adapter.iface.ILoadMoreSupportAdapter.IndicatorPosition
@@ -86,7 +84,6 @@ abstract class CursorStatusesFragment : AbsStatusesFragment() {
         } else {
             where = accountWhere
         }
-        val adapter = adapter
         adapter.showAccountsColor = accountKeys.size > 1
         val projection = Statuses.COLUMNS
         val selectionArgs = Array(accountKeys.size) {
@@ -103,8 +100,7 @@ abstract class CursorStatusesFragment : AbsStatusesFragment() {
 
 
     private fun showContentOrError() {
-        val accountKeys = accountKeys
-        val adapter = adapter
+        val accountKeys = this.accountKeys
         if (adapter.itemCount > 0) {
             showContent()
         } else if (accountKeys.isNotEmpty()) {
@@ -270,7 +266,6 @@ abstract class CursorStatusesFragment : AbsStatusesFragment() {
                 val status = event.status
                 val data = adapterData
                 if (status == null || data == null || data.isEmpty()) return
-                val adapter = adapter
                 val firstVisiblePosition = layoutManager.findFirstVisibleItemPosition()
                 val lastVisiblePosition = layoutManager.findLastVisibleItemPosition()
                 val startIndex = adapter.statusStartIndex
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CustomTabsFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CustomTabsFragment.kt
index c022f9b8a..e5344616f 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CustomTabsFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/CustomTabsFragment.kt
@@ -73,7 +73,7 @@ import org.mariotaku.twidere.view.holder.TwoLineWithIconViewHolder
 
 class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, MultiChoiceModeListener {
 
-    private var adapter: CustomTabsAdapter? = null
+    private lateinit var adapter: CustomTabsAdapter
 
     override fun onActionItemClicked(mode: ActionMode, item: MenuItem): Boolean {
         when (item.itemId) {
@@ -95,7 +95,7 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
         listView.choiceMode = ListView.CHOICE_MODE_MULTIPLE_MODAL
         listView.setMultiChoiceModeListener(this)
         listView.onItemClickListener = OnItemClickListener { parent, view, position, id ->
-            val tab = adapter!!.getTab(position)
+            val tab = adapter.getTab(position)
             val df = TabEditorDialogFragment()
             df.arguments = Bundle {
                 this[EXTRA_OBJECT] = tab
@@ -105,7 +105,7 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
         listView.adapter = adapter
         listView.emptyView = emptyView
         listView.setDropListener { from, to ->
-            adapter!!.drop(from, to)
+            adapter.drop(from, to)
             if (listView.choiceMode != AbsListView.CHOICE_MODE_NONE) {
                 listView.moveCheckState(from, to)
             }
@@ -132,7 +132,7 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
                     values.put(Tabs.TYPE, data.getStringExtra(EXTRA_TYPE))
                     values.put(Tabs.ARGUMENTS, data.getStringExtra(EXTRA_ARGUMENTS))
                     values.put(Tabs.EXTRAS, data.getStringExtra(EXTRA_EXTRAS))
-                    values.put(Tabs.POSITION, adapter!!.count)
+                    values.put(Tabs.POSITION, adapter.count)
                     contentResolver.insert(Tabs.CONTENT_URI, values)
                     SettingsActivity.setShouldRestart(activity)
                 }
@@ -187,7 +187,6 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
                     val df = TabEditorDialogFragment()
                     df.arguments = Bundle {
                         this[EXTRA_TAB_TYPE] = type
-                        val adapter = adapter!!
                         if (!adapter.isEmpty) {
                             this[EXTRA_TAB_POSITION] = adapter.getTab(adapter.count - 1).position + 1
                         }
@@ -214,11 +213,11 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
 
 
     override fun onLoaderReset(loader: Loader<Cursor?>) {
-        adapter!!.changeCursor(null)
+        adapter.changeCursor(null)
     }
 
     override fun onLoadFinished(loader: Loader<Cursor?>, cursor: Cursor?) {
-        adapter!!.changeCursor(cursor)
+        adapter.changeCursor(cursor)
         setListShown(true)
     }
 
@@ -242,8 +241,8 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
     }
 
     private fun saveTabPositions() {
-        val positions = adapter!!.cursorPositions
-        val c = adapter!!.cursor
+        val positions = adapter.cursorPositions
+        val c = adapter.cursor
         if (positions != null && c != null && !c.isClosed) {
             val idIdx = c.getColumnIndex(Tabs._ID)
             for (i in 0 until positions.size) {
@@ -368,7 +367,7 @@ class CustomTabsFragment : BaseSupportFragment(), LoaderCallbacks<Cursor?>, Mult
                 extraConfigContainer.addView(view)
             }
 
-            accountSpinner.onItemSelectedListener = object :AdapterView.OnItemSelectedListener {
+            accountSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
 
                 private fun updateExtraTabs(account: AccountDetails?) {
                     extraConfigurations.forEach {
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ExtensionsListFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ExtensionsListFragment.kt
index 717ab0752..222a8e8e2 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ExtensionsListFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ExtensionsListFragment.kt
@@ -44,7 +44,6 @@ import org.mariotaku.twidere.util.PermissionsManager
 
 class ExtensionsListFragment : BaseListFragment(), LoaderCallbacks<List<ExtensionInfo>> {
 
-    private var adapter: ExtensionsAdapter? = null
     private var packageManager: PackageManager? = null
     private var permissionsManager: PermissionsManager? = null
 
@@ -52,8 +51,7 @@ class ExtensionsListFragment : BaseListFragment(), LoaderCallbacks<List<Extensio
         super.onActivityCreated(savedInstanceState)
         packageManager = activity.packageManager
         permissionsManager = PermissionsManager(activity)
-        adapter = ExtensionsAdapter(activity)
-        listAdapter = adapter
+        listAdapter = ExtensionsAdapter(activity)
         listView.setOnCreateContextMenuListener(this)
         loaderManager.initLoader(0, null, this)
         setEmptyText(getString(R.string.no_extension_installed))
@@ -69,28 +67,28 @@ class ExtensionsListFragment : BaseListFragment(), LoaderCallbacks<List<Extensio
     }
 
     override fun onLoadFinished(loader: Loader<List<ExtensionInfo>>, data: List<ExtensionInfo>) {
-        adapter!!.setData(data)
+        (listAdapter as ExtensionsAdapter).setData(data)
         setListShown(true)
     }
 
     override fun onLoaderReset(loader: Loader<List<ExtensionInfo>>) {
-        adapter!!.setData(null)
+        (listAdapter as ExtensionsAdapter).setData(null)
     }
 
     override fun onListItemClick(l: ListView?, v: View?, position: Int, id: Long) {
-        openSettings(adapter!!.getItem(position))
+        openSettings((listAdapter as ExtensionsAdapter).getItem(position))
     }
 
     override fun onResume() {
         super.onResume()
-        adapter!!.notifyDataSetChanged()
+        (listAdapter as ExtensionsAdapter).notifyDataSetChanged()
     }
 
     override fun onCreateContextMenu(menu: ContextMenu, v: View, menuInfo: ContextMenuInfo) {
         val inflater = MenuInflater(v.context)
         inflater.inflate(R.menu.action_extension, menu)
         val adapterMenuInfo = menuInfo as AdapterContextMenuInfo
-        val extensionInfo = adapter!!.getItem(adapterMenuInfo.position)
+        val extensionInfo = (listAdapter as ExtensionsAdapter).getItem(adapterMenuInfo.position)
         if (extensionInfo.pname != null && extensionInfo.settings != null) {
             val intent = Intent(IntentConstants.INTENT_ACTION_EXTENSION_SETTINGS)
             intent.setClassName(extensionInfo.pname, extensionInfo.settings)
@@ -103,7 +101,7 @@ class ExtensionsListFragment : BaseListFragment(), LoaderCallbacks<List<Extensio
 
     override fun onContextItemSelected(item: MenuItem?): Boolean {
         val adapterMenuInfo = item!!.menuInfo as AdapterContextMenuInfo
-        val extensionInfo = adapter!!.getItem(adapterMenuInfo.position)
+        val extensionInfo = (listAdapter as ExtensionsAdapter).getItem(adapterMenuInfo.position)
         when (item.itemId) {
             R.id.settings -> {
                 openSettings(extensionInfo)
@@ -113,7 +111,7 @@ class ExtensionsListFragment : BaseListFragment(), LoaderCallbacks<List<Extensio
             }
             R.id.revoke -> {
                 permissionsManager!!.revoke(extensionInfo.pname)
-                adapter!!.notifyDataSetChanged()
+                (listAdapter as ExtensionsAdapter).notifyDataSetChanged()
             }
             else -> {
                 return false
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/IncomingFriendshipsFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/IncomingFriendshipsFragment.kt
index abcc59cd2..bdbf7f048 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/IncomingFriendshipsFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/IncomingFriendshipsFragment.kt
@@ -59,13 +59,11 @@ class IncomingFriendshipsFragment : CursorSupportUsersListFragment(), IUsersAdap
     }
 
     override fun onAcceptClicked(holder: UserViewHolder, position: Int) {
-        val adapter = adapter
         val user = adapter.getUser(position) ?: return
         twitterWrapper.acceptFriendshipAsync(user.account_key, user.key)
     }
 
     override fun onDenyClicked(holder: UserViewHolder, position: Int) {
-        val adapter = adapter
         val user = adapter.getUser(position) ?: return
         twitterWrapper.denyFriendshipAsync(user.account_key, user.key)
     }
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ItemsListFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ItemsListFragment.kt
index 468ec7f0f..82a7e3814 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ItemsListFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ItemsListFragment.kt
@@ -116,7 +116,6 @@ class ItemsListFragment : AbsContentListRecyclerViewFragment<VariousItemsAdapter
         val inflater = MenuInflater(context)
         val contextMenuInfo = menuInfo as ExtendedRecyclerView.ContextMenuInfo?
         val position = contextMenuInfo!!.position
-        val adapter = adapter
         when (adapter.getItemViewType(position)) {
             VariousItemsAdapter.VIEW_TYPE_STATUS -> {
                 val dummyAdapter = adapter.dummyAdapter
@@ -132,7 +131,6 @@ class ItemsListFragment : AbsContentListRecyclerViewFragment<VariousItemsAdapter
         if (!userVisibleHint) return false
         val contextMenuInfo = item!!.menuInfo as ExtendedRecyclerView.ContextMenuInfo
         val position = contextMenuInfo.position
-        val adapter = adapter
         when (adapter.getItemViewType(position)) {
             VariousItemsAdapter.VIEW_TYPE_STATUS -> {
                 val dummyAdapter = adapter.dummyAdapter
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableGroupsFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableGroupsFragment.kt
index 2d46a60ca..a8b1f09f2 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableGroupsFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableGroupsFragment.kt
@@ -76,7 +76,6 @@ abstract class ParcelableGroupsFragment : AbsContentListRecyclerViewFragment<Par
     }
 
     override fun onLoadFinished(loader: Loader<List<ParcelableGroup>?>, data: List<ParcelableGroup>?) {
-        val adapter = adapter
         adapter.setData(data)
         if (loader !is IExtendedLoader || loader.fromUser) {
             adapter.loadMoreSupportedPosition = if (hasMoreData(data)) ILoadMoreSupportAdapter.END else ILoadMoreSupportAdapter.NONE
@@ -123,7 +122,6 @@ abstract class ParcelableGroupsFragment : AbsContentListRecyclerViewFragment<Par
 
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
-        val adapter = adapter
         val layoutManager = layoutManager
         adapter.groupAdapterListener = this
 
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableStatusesFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableStatusesFragment.kt
index b00713d44..63e61bfaa 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableStatusesFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableStatusesFragment.kt
@@ -128,7 +128,6 @@ abstract class ParcelableStatusesFragment : AbsStatusesFragment() {
         refreshEnabled = true
         refreshing = false
         setLoadMoreIndicatorPosition(ILoadMoreSupportAdapter.NONE)
-        val adapter = adapter
         if (adapter.itemCount > 0) {
             showContent()
         } else if (loader is MicroBlogAPIStatusesLoader) {
@@ -149,7 +148,6 @@ abstract class ParcelableStatusesFragment : AbsStatusesFragment() {
         if (position and ILoadMoreSupportAdapter.START !== 0L || refreshing) return
         super.onLoadMoreContents(position)
         if (position == 0L) return
-        val adapter = adapter
         // Load the last item
         val idx = adapter.statusStartIndex + adapter.rawStatusCount - 1
         if (idx < 0) return
@@ -165,7 +163,6 @@ abstract class ParcelableStatusesFragment : AbsStatusesFragment() {
     fun replaceStatusStates(status: ParcelableStatus?) {
         if (status == null) return
         val lm = layoutManager
-        val adapter = adapter
         val rangeStart = Math.max(adapter.statusStartIndex, lm.findFirstVisibleItemPosition())
         val rangeEnd = Math.min(lm.findLastVisibleItemPosition(), adapter.statusStartIndex + adapter.statusCount - 1)
         for (i in rangeStart..rangeEnd) {
@@ -183,7 +180,6 @@ abstract class ParcelableStatusesFragment : AbsStatusesFragment() {
 
     override fun triggerRefresh(): Boolean {
         super.triggerRefresh()
-        val adapter = adapter
         val accountKeys = accountKeys
         if (adapter.statusCount > 0) {
             val firstStatus = adapter.getStatus(0)!!
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUserListsFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUserListsFragment.kt
index d162d00f2..6d7851797 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUserListsFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUserListsFragment.kt
@@ -78,7 +78,6 @@ abstract class ParcelableUserListsFragment : AbsContentListRecyclerViewFragment<
     }
 
     override fun onLoadFinished(loader: Loader<List<ParcelableUserList>>, data: List<ParcelableUserList>) {
-        val adapter = adapter
         adapter.setData(data)
         if (loader !is IExtendedLoader || loader.fromUser) {
             adapter.loadMoreSupportedPosition = if (hasMoreData(data)) ILoadMoreSupportAdapter.END else ILoadMoreSupportAdapter.NONE
@@ -129,7 +128,6 @@ abstract class ParcelableUserListsFragment : AbsContentListRecyclerViewFragment<
 
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
-        val adapter = adapter
         val layoutManager = layoutManager
         adapter.userListClickListener = this
 
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUsersFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUsersFragment.kt
index 00a72df89..8e214e6ef 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUsersFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/ParcelableUsersFragment.kt
@@ -63,7 +63,6 @@ abstract class ParcelableUsersFragment : AbsContentListRecyclerViewFragment<Parc
 
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
-        val adapter = adapter
         adapter.userClickListener = this
 
         navigationHelper = RecyclerViewNavigationHelper(recyclerView, layoutManager, adapter,
@@ -99,7 +98,6 @@ abstract class ParcelableUsersFragment : AbsContentListRecyclerViewFragment<Parc
     }
 
     override fun onLoadFinished(loader: Loader<List<ParcelableUser>?>, data: List<ParcelableUser>?) {
-        val adapter = adapter
         adapter.setData(data)
         if (loader !is IExtendedLoader || loader.fromUser) {
             adapter.loadMoreSupportedPosition = if (hasMoreData(data)) ILoadMoreSupportAdapter.END else ILoadMoreSupportAdapter.NONE
@@ -183,7 +181,6 @@ abstract class ParcelableUsersFragment : AbsContentListRecyclerViewFragment<Parc
 
     override fun createItemDecoration(context: Context, recyclerView: RecyclerView,
                                       layoutManager: LinearLayoutManager): RecyclerView.ItemDecoration? {
-        val adapter = adapter
         val itemDecoration = DividerItemDecoration(context,
                 (recyclerView.layoutManager as LinearLayoutManager).orientation)
         val res = context.resources
@@ -227,7 +224,6 @@ abstract class ParcelableUsersFragment : AbsContentListRecyclerViewFragment<Parc
 
         @Subscribe
         fun onFriendshipTaskEvent(event: FriendshipTaskEvent) {
-            val adapter = adapter
             val position = findPosition(event.accountKey, event.userKey)
             val data = adapter.getData() ?: return
             if (position < 0 || position >= data.size) return
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/StatusFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/StatusFragment.kt
index 360a775d3..628ebda36 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/StatusFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/StatusFragment.kt
@@ -120,7 +120,8 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         OnMediaClickListener, StatusClickListener, KeyboardShortcutCallback, ContentListSupport {
     private var mItemDecoration: DividerItemDecoration? = null
 
-    override var adapter: StatusAdapter? = null
+    override lateinit var adapter: StatusAdapter
+        private set
 
     private var layoutManager: LinearLayoutManager? = null
     private var loadTranslationTask: LoadTranslationTask? = null
@@ -136,7 +137,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     // Listeners
     private val conversationsLoaderCallback = object : LoaderCallbacks<List<ParcelableStatus>> {
         override fun onCreateLoader(id: Int, args: Bundle): Loader<List<ParcelableStatus>> {
-            val adapter = this@StatusFragment.adapter!!
+            val adapter = this@StatusFragment.adapter
             adapter.isRepliesLoading = true
             adapter.isConversationsLoading = true
             adapter.updateItemDecoration()
@@ -154,7 +155,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         }
 
         override fun onLoadFinished(loader: Loader<List<ParcelableStatus>>, data: List<ParcelableStatus>?) {
-            val adapter = this@StatusFragment.adapter!!
+            val adapter = this@StatusFragment.adapter
             adapter.updateItemDecoration()
             val conversationLoader = loader as ConversationLoader
             var supportedPositions: Long = 0
@@ -215,8 +216,8 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         }
 
         override fun onLoadFinished(loader: Loader<StatusActivity?>, data: StatusActivity?) {
-            adapter!!.updateItemDecoration()
-            adapter!!.statusActivity = data
+            adapter.updateItemDecoration()
+            adapter.statusActivity = data
         }
 
         override fun onLoaderReset(loader: Loader<StatusActivity?>) {
@@ -228,7 +229,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         val activity = activity ?: return
         when (requestCode) {
             REQUEST_SET_COLOR -> {
-                val status = adapter!!.status ?: return
+                val status = adapter.status ?: return
                 if (resultCode == Activity.RESULT_OK) {
                     if (data == null) return
                     val color = data.getIntExtra(EXTRA_COLOR, Color.TRANSPARENT)
@@ -245,7 +246,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
                 loaderManager.restartLoader(LOADER_ID_DETAIL_STATUS, args, this)
             }
             REQUEST_SELECT_ACCOUNT -> {
-                val status = adapter!!.status ?: return
+                val status = adapter.status ?: return
                 if (resultCode == Activity.RESULT_OK) {
                     if (data == null || !data.hasExtra(EXTRA_ID)) return
                     val accountKey = data.getParcelableExtra<UserKey>(EXTRA_ACCOUNT_KEY)
@@ -271,12 +272,12 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         })
         adapter = StatusAdapter(this)
         layoutManager = StatusListLinearLayoutManager(context, recyclerView)
-        mItemDecoration = StatusDividerItemDecoration(context, adapter!!, layoutManager!!.orientation)
+        mItemDecoration = StatusDividerItemDecoration(context, adapter, layoutManager!!.orientation)
         recyclerView.addItemDecoration(mItemDecoration)
         layoutManager!!.recycleChildrenOnDetach = true
         recyclerView.layoutManager = layoutManager
         recyclerView.clipToPadding = false
-        adapter!!.statusClickListener = this
+        adapter.statusClickListener = this
         recyclerView.adapter = adapter
         registerForContextMenu(recyclerView!!)
 
@@ -285,7 +286,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         scrollListener!!.touchSlop = ViewConfiguration.get(context).scaledTouchSlop
 
         navigationHelper = RecyclerViewNavigationHelper(recyclerView!!, layoutManager!!,
-                adapter!!, null)
+                adapter, null)
 
         setState(STATE_LOADING)
 
@@ -293,12 +294,12 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     }
 
     override fun onMediaClick(holder: IStatusViewHolder, view: View, media: ParcelableMedia, statusPosition: Int) {
-        val status = adapter!!.getStatus(statusPosition) ?: return
+        val status = adapter.getStatus(statusPosition) ?: return
         IntentUtils.openMedia(activity, status, media, null,
                 preferences.getBoolean(SharedPreferenceConstants.KEY_NEW_DOCUMENT_API))
 
         val event = MediaEvent.create(activity, status, media, TimelineType.DETAILS,
-                adapter!!.mediaPreviewEnabled)
+                adapter.mediaPreviewEnabled)
         HotMobiLogger.getInstance(activity).log(status.account_key, event)
     }
 
@@ -308,13 +309,13 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     }
 
     override fun onItemActionClick(holder: ViewHolder, id: Int, position: Int) {
-        val status = adapter!!.getStatus(position)
+        val status = adapter.getStatus(position)
         AbsStatusesFragment.handleStatusActionClick(context, fragmentManager, twitterWrapper,
                 holder as StatusViewHolder, status, id)
     }
 
     override fun onStatusClick(holder: IStatusViewHolder, position: Int) {
-        IntentUtils.openStatus(activity, adapter!!.getStatus(position)!!, null)
+        IntentUtils.openStatus(activity, adapter.getStatus(position)!!, null)
     }
 
     override fun onStatusLongClick(holder: IStatusViewHolder, position: Int): Boolean {
@@ -329,20 +330,20 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
 
     override fun onUserProfileClick(holder: IStatusViewHolder, position: Int) {
         val activity = activity
-        val status = adapter!!.getStatus(position)
+        val status = adapter.getStatus(position)
         IntentUtils.openUserProfile(activity, status!!.account_key, status.user_key,
                 status.user_screen_name, null, preferences.getBoolean(KEY_NEW_DOCUMENT_API),
                 Referral.TIMELINE_STATUS)
     }
 
     override fun onMediaClick(view: View, media: ParcelableMedia?, accountKey: UserKey, extraId: Long) {
-        val status = adapter!!.status
+        val status = adapter.status
         if (status == null || media == null) return
         IntentUtils.openMediaDirectly(activity, accountKey, status, media, null,
                 preferences.getBoolean(KEY_NEW_DOCUMENT_API))
         // BEGIN HotMobi
         val event = MediaEvent.create(activity, status, media, TimelineType.OTHER,
-                adapter!!.mediaPreviewEnabled)
+                adapter.mediaPreviewEnabled)
         HotMobiLogger.getInstance(activity).log(status.account_key, event)
         // END HotMobi
     }
@@ -359,7 +360,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
             return false
         }
         if (position == -1) return false
-        val status = adapter!!.getStatus(position) ?: return false
+        val status = adapter.getStatus(position) ?: return false
         val action = handler.getKeyAction(CONTEXT_TAG_STATUS, keyCode, event, metaState) ?: return false
         when (action) {
             ACTION_STATUS_REPLY -> {
@@ -416,17 +417,17 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
             val readPosition = saveReadPosition()
             val dataExtra = data.extras
             val details: AccountDetails = dataExtra.getParcelable(EXTRA_ACCOUNT)
-            if (adapter!!.setStatus(status, details)) {
+            if (adapter.setStatus(status, details)) {
                 val args = arguments
                 if (args.containsKey(EXTRA_STATUS)) {
                     args.putParcelable(EXTRA_STATUS, status)
                 }
-                adapter!!.loadMoreSupportedPosition = ILoadMoreSupportAdapter.BOTH
-                adapter!!.setData(null)
+                adapter.loadMoreSupportedPosition = ILoadMoreSupportAdapter.BOTH
+                adapter.setData(null)
                 loadConversation(status, null, null)
                 loadActivity(status)
 
-                val position = adapter!!.getFirstPositionOfItem(StatusAdapter.ITEM_IDX_STATUS)
+                val position = adapter.getFirstPositionOfItem(StatusAdapter.ITEM_IDX_STATUS)
                 if (position != RecyclerView.NO_POSITION) {
                     layoutManager!!.scrollToPositionWithOffset(position, 0)
                 }
@@ -440,7 +441,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
             }
             setState(STATE_LOADED)
         } else {
-            adapter!!.loadMoreSupportedPosition = ILoadMoreSupportAdapter.NONE
+            adapter.loadMoreSupportedPosition = ILoadMoreSupportAdapter.NONE
             setState(STATE_ERROR)
             errorText.text = Utils.getErrorMessage(context, data.exception)
         }
@@ -459,15 +460,15 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     }
 
     override fun onPrepareOptionsMenu(menu: Menu?) {
-        MenuUtils.setItemAvailability(menu, R.id.current_status, adapter!!.status != null)
+        MenuUtils.setItemAvailability(menu, R.id.current_status, adapter.status != null)
         super.onPrepareOptionsMenu(menu)
     }
 
     override fun onOptionsItemSelected(item: MenuItem?): Boolean {
         when (item!!.itemId) {
             R.id.current_status -> {
-                if (adapter!!.status != null) {
-                    val position = adapter!!.getFirstPositionOfItem(StatusAdapter.ITEM_IDX_STATUS)
+                if (adapter.status != null) {
+                    val position = adapter.getFirstPositionOfItem(StatusAdapter.ITEM_IDX_STATUS)
                     recyclerView!!.smoothScrollToPosition(position)
                 }
                 return true
@@ -478,7 +479,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
 
     private fun setConversation(data: List<ParcelableStatus>?) {
         val readPosition = saveReadPosition()
-        val changed = adapter!!.setData(data)
+        val changed = adapter.setData(data)
         hasMoreConversation = data != null && changed
         restoreReadPosition(readPosition)
     }
@@ -489,16 +490,16 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     override fun onLoadMoreContents(@IndicatorPosition position: Long) {
         if (!hasMoreConversation) return
         if (position and ILoadMoreSupportAdapter.START !== 0L) {
-            val start = adapter!!.getIndexStart(StatusAdapter.ITEM_IDX_CONVERSATION)
-            val status = adapter!!.getStatus(start)
+            val start = adapter.getIndexStart(StatusAdapter.ITEM_IDX_CONVERSATION)
+            val status = adapter.getStatus(start)
             if (status == null || status.in_reply_to_status_id == null) return
             loadConversation(status, null, status.id)
         } else if (position and ILoadMoreSupportAdapter.END !== 0L) {
-            val start = adapter!!.getIndexStart(StatusAdapter.ITEM_IDX_CONVERSATION)
-            val status = adapter!!.getStatus(start + adapter!!.statusCount - 1) ?: return
+            val start = adapter.getIndexStart(StatusAdapter.ITEM_IDX_CONVERSATION)
+            val status = adapter.getStatus(start + adapter.statusCount - 1) ?: return
             loadConversation(status, status.id, null)
         }
-        adapter!!.loadMoreIndicatorPosition = position
+        adapter.loadMoreIndicatorPosition = position
     }
 
     override fun setControlVisible(visible: Boolean) {
@@ -506,13 +507,13 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     }
 
     override val reachingEnd: Boolean
-        get() = layoutManager!!.findLastCompletelyVisibleItemPosition() >= adapter!!.itemCount - 1
+        get() = layoutManager!!.findLastCompletelyVisibleItemPosition() >= adapter.itemCount - 1
 
     override val reachingStart: Boolean
         get() = layoutManager!!.findFirstCompletelyVisibleItemPosition() <= 1
 
     private val status: ParcelableStatus?
-        get() = adapter!!.status
+        get() = adapter.status
 
     private fun loadConversation(status: ParcelableStatus?, sinceId: String?, maxId: String?) {
         if (status == null || activity == null) return
@@ -555,7 +556,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
 
 
     private fun displayTranslation(translation: TranslationResult) {
-        adapter?.translationResult = translation
+        adapter.translationResult = translation
         val status = this.status
         val context = this.context ?: return
         if (status != null) {
@@ -566,7 +567,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
 
     private fun saveReadPosition(): ReadPosition? {
         val lm = layoutManager ?: return null
-        val adapter = this.adapter ?: return null
+        val adapter = this.adapter
         val position = lm.findFirstVisibleItemPosition()
         if (position == RecyclerView.NO_POSITION) return null
         val itemType = adapter.getItemType(position)
@@ -583,7 +584,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     }
 
     private fun restoreReadPosition(position: ReadPosition?) {
-        val adapter = this.adapter ?: return
+        val adapter = this.adapter
         if (position == null) return
         val adapterPosition = adapter.findPositionByItemId(position.statusId)
         if (adapterPosition < 0) return
@@ -619,7 +620,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
         if (!userVisibleHint || menuInfo == null) return
         val inflater = MenuInflater(context)
         val contextMenuInfo = menuInfo as ExtendedRecyclerView.ContextMenuInfo?
-        val status = adapter!!.getStatus(contextMenuInfo!!.position)
+        val status = adapter.getStatus(contextMenuInfo!!.position)
         inflater.inflate(R.menu.action_status, menu)
         MenuUtils.setupForStatus(context, preferences, menu, status!!,
                 twitterWrapper)
@@ -628,7 +629,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
     override fun onContextItemSelected(item: MenuItem?): Boolean {
         if (!userVisibleHint) return false
         val contextMenuInfo = item!!.menuInfo as ExtendedRecyclerView.ContextMenuInfo
-        val status = adapter!!.getStatus(contextMenuInfo.position) ?: return false
+        val status = adapter.getStatus(contextMenuInfo.position) ?: return false
         if (item.itemId == R.id.share) {
             val shareIntent = Utils.createStatusShareIntent(activity, status)
             val chooser = Intent.createChooser(shareIntent, getString(R.string.share_status))
@@ -641,15 +642,13 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
 
     @Subscribe
     fun notifyStatusListChanged(event: StatusListChangedEvent) {
-        val adapter = adapter
-        adapter!!.notifyDataSetChanged()
+        adapter.notifyDataSetChanged()
     }
 
     @Subscribe
     fun notifyFavoriteTask(event: FavoriteTaskEvent) {
         if (!event.isSucceeded) return
-        val adapter = adapter
-        val status = adapter!!.findStatusById(event.accountKey, event.statusId)
+        val status = adapter.findStatusById(event.accountKey, event.statusId)
         if (status != null) {
             when (event.action) {
                 FavoriteTaskEvent.Action.CREATE -> {
@@ -675,7 +674,7 @@ class StatusFragment : BaseSupportFragment(), LoaderCallbacks<SingleResponse<Par
                     val f = parentFragment
                     if (f is StatusFragment) {
                         val adapter = f.adapter
-                        adapter!!.isDetailMediaExpanded = true
+                        adapter.isDetailMediaExpanded = true
                     }
                 }
             }
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListMembersFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListMembersFragment.kt
index 363aa1ded..b094de72a 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListMembersFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListMembersFragment.kt
@@ -87,7 +87,6 @@ class UserListMembersFragment : CursorSupportUsersListFragment() {
         val accountId = args.getParcelable<UserKey>(EXTRA_ACCOUNT_KEY)
         val userKey = args.getParcelable<UserKey>(EXTRA_USER_KEY)
         if (accountId == null || accountId != userKey) return
-        val adapter = adapter
         val inflater = MenuInflater(context)
         val contextMenuInfo = menuInfo as ExtendedRecyclerView.ContextMenuInfo?
         inflater.inflate(R.menu.action_user_list_member, menu)
@@ -132,7 +131,6 @@ class UserListMembersFragment : CursorSupportUsersListFragment() {
         }
         when (event.action) {
             UserListMembersChangedEvent.Action.ADDED -> {
-                val adapter = adapter
                 val newUsers = Arrays.asList(*event.users)
                 val users = adapter.getData() ?: return
                 if (users is MutableList) {
@@ -143,7 +141,6 @@ class UserListMembersFragment : CursorSupportUsersListFragment() {
                 adapter.notifyDataSetChanged()
             }
             UserListMembersChangedEvent.Action.REMOVED -> {
-                val adapter = adapter
                 val removedUsers = Arrays.asList(*event.users)
                 val users = adapter.getData() ?: return
                 if (users is MutableList) {
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListsFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListsFragment.kt
index 023283bfa..9707dcfe6 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListsFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserListsFragment.kt
@@ -101,7 +101,6 @@ class UserListsFragment : ParcelableUserListsFragment() {
     }
 
     private fun removeUserList(id: String) {
-        val adapter = adapter
         //        final int listsIdx = adapter.findItemPosition(id);
         //        if (listsIdx >= 0) {
         //            adapter.removeAt(listsIdx);
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserMediaTimelineFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserMediaTimelineFragment.kt
index 0e4dd5328..01b06e709 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserMediaTimelineFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserMediaTimelineFragment.kt
@@ -47,7 +47,6 @@ class UserMediaTimelineFragment : AbsContentRecyclerViewFragment<StaggeredGridPa
 
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
-        val adapter = adapter
         adapter.statusClickListener = this
         val loaderArgs = Bundle(arguments)
         loaderArgs.putBoolean(EXTRA_FROM_USER, true)
@@ -99,7 +98,6 @@ class UserMediaTimelineFragment : AbsContentRecyclerViewFragment<StaggeredGridPa
     }
 
     override fun onLoadFinished(loader: Loader<List<ParcelableStatus>>, data: List<ParcelableStatus>?) {
-        val adapter = adapter
         val changed = adapter.setData(data)
         if ((loader as IExtendedLoader).fromUser && loader is MediaTimelineLoader) {
             val maxId = loader.maxId
@@ -138,7 +136,6 @@ class UserMediaTimelineFragment : AbsContentRecyclerViewFragment<StaggeredGridPa
         if (position and ILoadMoreSupportAdapter.START != 0L) return
         super.onLoadMoreContents(position)
         if (position == 0L) return
-        val adapter = adapter
         val maxId = adapter.getStatusId(adapter.statusCount - 1)
         getStatuses(maxId, null)
     }
diff --git a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserTimelineFragment.kt b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserTimelineFragment.kt
index fb3d59144..833f85c17 100644
--- a/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserTimelineFragment.kt
+++ b/twidere/src/main/kotlin/org/mariotaku/twidere/fragment/UserTimelineFragment.kt
@@ -99,7 +99,6 @@ class UserTimelineFragment : ParcelableStatusesFragment() {
 
     override fun onStatusesLoaded(loader: Loader<List<ParcelableStatus>?>, data: List<ParcelableStatus>?) {
         val timelineLoader = loader as UserTimelineLoader
-        val adapter = adapter
         if (!adapter.hasPinnedStatuses) {
             adapter.pinnedStatuses = timelineLoader.pinnedStatuses
         }