Use isEmpty() extension functions.

app/src/main/java/com/github/libretube/api/PlaylistsHelper.kt

@@ -104,7 +104,7 @@ object PlaylistsHelper {
                 DatabaseHolder.Database.localPlaylistsDao().addPlaylistVideo(localPlaylistItem)
 
                 val playlist = localPlaylist.playlist
-                if (playlist.thumbnailUrl == "") {
+                if (playlist.thumbnailUrl.isEmpty()) {
                     // set the new playlist thumbnail URL
                     localPlaylistItem.thumbnailUrl?.let {
                         playlist.thumbnailUrl = it

app/src/main/java/com/github/libretube/ui/activities/MainActivity.kt

@@ -291,13 +291,12 @@ class MainActivity : BaseActivity() {
                 }
 
                 // prevent malicious navigation when the search view is getting collapsed
-                if (navController.currentDestination?.id in listOf(
+                val destIds = listOf(
-                        R.id.searchResultFragment,
+                    R.id.searchResultFragment,
-                        R.id.channelFragment,
+                    R.id.channelFragment,
-                        R.id.playlistFragment
+                    R.id.playlistFragment
-                    ) &&
+                )
-                    (newText == null || newText == "")
+                if (navController.currentDestination?.id in destIds && newText.isNullOrEmpty()) {
-                ) {
                     return false
                 }
 

app/src/main/java/com/github/libretube/ui/dialogs/CreatePlaylistDialog.kt

@@ -53,8 +53,8 @@ class CreatePlaylistDialog(
         binding.createNewPlaylist.setOnClickListener {
             // avoid creating the same playlist multiple times by spamming the button
             binding.createNewPlaylist.setOnClickListener(null)
-            val listName = binding.playlistName.text.toString()
+            val listName = binding.playlistName.text?.toString()
-            if (listName != "") {
+            if (!listName.isNullOrEmpty()) {
                 lifecycleScope.launch {
                     requireDialog().hide()
                     val playlistId = withContext(Dispatchers.IO) {

app/src/main/java/com/github/libretube/ui/dialogs/DeleteAccountDialog.kt

@@ -27,8 +27,9 @@ class DeleteAccountDialog(
         }
 
         binding.deleteAccountConfirm.setOnClickListener {
-            if (binding.deletePassword.text.toString() != "") {
+            val password = binding.deletePassword.text?.toString()
-                deleteAccount(binding.deletePassword.text.toString())
+            if (!password.isNullOrEmpty()) {
+                deleteAccount(password)
             } else {
                 Toast.makeText(context, R.string.empty, Toast.LENGTH_SHORT).show()
             }

app/src/main/java/com/github/libretube/ui/dialogs/LoginDialog.kt

@@ -28,35 +28,30 @@ class LoginDialog(
         binding = DialogLoginBinding.inflate(layoutInflater)
 
         binding.login.setOnClickListener {
-            if (isInsertionValid()) {
+            val email = binding.username.text?.toString()
-                signIn(
+            val password = binding.password.text?.toString()
-                    binding.username.text.toString(),
+
-                    binding.password.text.toString()
+            if (!email.isNullOrEmpty() && !password.isNullOrEmpty()) {
-                )
+                signIn(email, password)
             } else {
                 Toast.makeText(context, R.string.empty, Toast.LENGTH_SHORT).show()
             }
         }
         binding.register.setOnClickListener {
-            if (isEmail(binding.username.text.toString())) {
+            val email = binding.username.text?.toString().orEmpty()
+            val password = binding.password.text?.toString().orEmpty()
+
+            if (isEmail(email)) {
                 MaterialAlertDialogBuilder(requireContext())
                     .setTitle(R.string.privacy_alert)
                     .setMessage(R.string.username_email)
                     .setNegativeButton(R.string.proceed) { _, _ ->
-                        signIn(
+                        signIn(email, password, true)
-                            binding.username.text.toString(),
-                            binding.password.text.toString(),
-                            true
-                        )
                     }
                     .setPositiveButton(R.string.cancel, null)
                     .show()
-            } else if (isInsertionValid()) {
+            } else if (email.isNotEmpty() && password.isNotEmpty()) {
-                signIn(
+                signIn(email, password, true)
-                    binding.username.text.toString(),
-                    binding.password.text.toString(),
-                    true
-                )
             } else {
                 Toast.makeText(context, R.string.empty, Toast.LENGTH_SHORT).show()
             }
@@ -67,10 +62,6 @@ class LoginDialog(
             .show()
     }
 
-    private fun isInsertionValid(): Boolean {
-        return binding.username.text.toString() != "" && binding.password.text.toString() != ""
-    }
-
     private fun signIn(username: String, password: String, createNewAccount: Boolean = false) {
         val login = Login(username, password)
         lifecycleScope.launchWhenCreated {

app/src/main/java/com/github/libretube/ui/dialogs/RenamePlaylistDialog.kt

@@ -36,13 +36,10 @@ class RenamePlaylistDialog(
             .show()
             .apply {
                 getButton(DialogInterface.BUTTON_POSITIVE).setOnClickListener {
-                    val input = binding.input.text.toString()
+                    val input = binding.input.text?.toString()
-                    if (input == "") {
+                    if (input.isNullOrEmpty()) {
-                        Toast.makeText(
+                        Toast.makeText(context, R.string.emptyPlaylistName, Toast.LENGTH_SHORT)
-                            context,
+                            .show()
-                            R.string.emptyPlaylistName,
-                            Toast.LENGTH_SHORT
-                        ).show()
                         return@setOnClickListener
                     }
                     if (input == currentPlaylistName) return@setOnClickListener

app/src/main/java/com/github/libretube/ui/fragments/PlayerFragment.kt

@@ -1270,7 +1270,7 @@ class PlayerFragment : Fragment(R.layout.fragment_player), OnlinePlayerOptions {
 
     private fun setStreamSource() {
         val defaultResolution = PlayerHelper.getDefaultResolution(requireContext()).replace("p", "")
-        if (defaultResolution != "") setPlayerResolution(defaultResolution.toInt())
+        if (defaultResolution.isNotEmpty()) setPlayerResolution(defaultResolution.toInt())
 
         if (!PreferenceHelper.getBoolean(PreferenceKeys.USE_HLS_OVER_DASH, false) &&
             streams.videoStreams.isNotEmpty()

app/src/main/java/com/github/libretube/ui/fragments/SearchFragment.kt

@@ -51,7 +51,7 @@ class SearchFragment : Fragment(R.layout.fragment_search) {
         // fetch the search or history
         binding.historyEmpty.visibility = View.GONE
         binding.suggestionsRecycler.visibility = View.VISIBLE
-        if (query == null || query == "") {
+        if (query.isNullOrEmpty()) {
             showHistory()
         } else {
             fetchSuggestions(query)
@@ -71,7 +71,7 @@ class SearchFragment : Fragment(R.layout.fragment_search) {
                 response.reversed(),
                 (activity as MainActivity).searchView
             )
-            if (isAdded && viewModel.searchQuery.value != "") {
+            if (isAdded && !viewModel.searchQuery.value.isNullOrEmpty()) {
                 binding.suggestionsRecycler.adapter = suggestionsAdapter
             }
         }

app/src/main/java/com/github/libretube/workers/NotificationWorker.kt

@@ -99,7 +99,7 @@ class NotificationWorker(appContext: Context, parameters: WorkerParameters) :
         val latestFeedStreamId = videoFeed.firstOrNull()?.url?.toID() ?: return true
 
         // first time notifications are enabled or no new video available
-        if (lastSeenStreamId == "" || lastSeenStreamId == latestFeedStreamId) {
+        if (lastSeenStreamId.isEmpty() || lastSeenStreamId == latestFeedStreamId) {
             PreferenceHelper.setLatestVideoId(lastSeenStreamId)
             return true
         }