refactor: simplify logic of loading comments and replies

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

@@ -4,7 +4,6 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.core.view.isGone
 import androidx.core.view.isVisible
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
@@ -72,23 +71,26 @@ class CommentsMainFragment : Fragment() {
         }
         binding.commentsRV.adapter = commentsAdapter
 
-        if (viewModel.commentsPage.value?.comments.orEmpty().isEmpty()) {
-            binding.progress.isVisible = true
+        if (viewModel.commentsPage.value?.comments.isNullOrEmpty()) {
             viewModel.fetchComments()
         } else {
             binding.commentsRV.scrollToPosition(viewModel.currentCommentsPosition)
         }
 
+        viewModel.isLoading.observe(viewLifecycleOwner) {
+            _binding?.progress?.isVisible = it == true
+        }
+
         // listen for new comments to be loaded
         viewModel.commentsPage.observe(viewLifecycleOwner) {
+            if (it == null) return@observe
             val viewBinding = _binding ?: return@observe
 
-            if (it == null) return@observe
-            viewBinding.progress.isGone = true
             if (it.disabled) {
                 viewBinding.errorTV.isVisible = true
                 return@observe
             }
+
             commentsSheet?.updateFragmentInfo(
                 false,
                 "${getString(R.string.comments)} (${it.commentCount.formatShort()})"

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

@@ -82,13 +82,11 @@ class CommentsRepliesFragment : Fragment() {
                 ::repliesPage.isInitialized &&
                 repliesPage.nextpage != null
             ) {
-                fetchReplies(videoId, repliesPage.nextpage!!) {
-                    repliesAdapter.updateItems(repliesPage.comments)
-                }
+                fetchReplies(videoId, repliesPage.nextpage!!)
             }
         }
 
-        loadInitialReplies(videoId, comment.repliesPage.orEmpty(), repliesAdapter)
+        loadInitialReplies(videoId, comment.repliesPage.orEmpty())
     }
 
     override fun onDestroyView() {
@@ -98,34 +96,32 @@ class CommentsRepliesFragment : Fragment() {
 
     private fun loadInitialReplies(
         videoId: String,
-        nextPage: String,
-        repliesAdapter: CommentsAdapter
+        nextPage: String
     ) {
         _binding?.progress?.isVisible = true
-        fetchReplies(videoId, nextPage) {
-            repliesAdapter.updateItems(it.comments)
-            _binding?.progress?.isGone = true
-        }
+        fetchReplies(videoId, nextPage)
     }
 
-    private fun fetchReplies(
-        videoId: String,
-        nextPage: String,
-        onFinished: (CommentsPage) -> Unit
-    ) {
-        lifecycleScope.launch(Dispatchers.IO) {
+    private fun fetchReplies(videoId: String, nextPage: String) {
+        _binding?.progress?.isVisible = true
+
+        lifecycleScope.launch {
             if (isLoading) return@launch
             isLoading = true
 
             repliesPage = try {
-                RetrofitInstance.api.getCommentsNextPage(videoId, nextPage)
+                withContext(Dispatchers.IO) {
+                    RetrofitInstance.api.getCommentsNextPage(videoId, nextPage)
+                }
             } catch (e: Exception) {
                 Log.e(TAG(), "IOException, you might not have internet connection")
                 return@launch
+            } finally {
+                _binding?.progress?.isGone = true
             }
             repliesPage.comments = repliesPage.comments.filterNonEmptyComments()
             withContext(Dispatchers.Main) {
-                onFinished.invoke(repliesPage)
+                repliesAdapter.updateItems(repliesPage.comments)
             }
             isLoading = false
         }

app/src/main/java/com/github/libretube/ui/models/CommentsViewModel.kt

@@ -10,6 +10,7 @@ import com.github.libretube.extensions.TAG
 import com.github.libretube.ui.extensions.filterNonEmptyComments
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 
 class CommentsViewModel : ViewModel() {
     val commentsPage = MutableLiveData<CommentsPage?>()
@@ -17,11 +18,12 @@ class CommentsViewModel : ViewModel() {
 
     var videoId: String? = null
     var channelAvatar: String? = null
+    var handleLink: ((url: String) -> Unit)? = null
+
     private var nextPage: String? = null
-    private var isLoading = false
+    var isLoading = MutableLiveData<Boolean>()
     var currentCommentsPosition = 0
     var commentsSheetDismiss: (() -> Unit)? = null
-    var handleLink: ((url: String) -> Unit)? = null
 
     fun setCommentSheetExpand(value: Boolean?) {
         if (commentSheetExpand.value != value) {
@@ -30,31 +32,43 @@ class CommentsViewModel : ViewModel() {
     }
 
     fun fetchComments() {
-        videoId ?: return
-        viewModelScope.launch(Dispatchers.IO) {
-            isLoading = true
+        val videoId = videoId ?: return
+
+        isLoading.value = true
+
+        viewModelScope.launch {
             val response = try {
-                RetrofitInstance.api.getComments(videoId!!)
+                withContext(Dispatchers.IO) {
+                    RetrofitInstance.api.getComments(videoId)
+                }
             } catch (e: Exception) {
                 Log.e(TAG(), e.toString())
                 return@launch
+            } finally {
+                isLoading.value = false
             }
+
             nextPage = response.nextpage
             response.comments = response.comments.filterNonEmptyComments()
             commentsPage.postValue(response)
-            isLoading = false
         }
     }
 
     fun fetchNextComments() {
-        if (isLoading || nextPage == null || videoId == null) return
-        viewModelScope.launch(Dispatchers.IO) {
-            isLoading = true
+        if (isLoading.value == true || nextPage == null || videoId == null) return
+
+        isLoading.value = true
+
+        viewModelScope.launch {
             val response = try {
-                RetrofitInstance.api.getCommentsNextPage(videoId!!, nextPage!!)
+                withContext(Dispatchers.IO) {
+                    RetrofitInstance.api.getCommentsNextPage(videoId!!, nextPage!!)
+                }
             } catch (e: Exception) {
                 Log.e(TAG(), e.toString())
                 return@launch
+            } finally {
+                isLoading.value = false
             }
 
             val updatedPage = commentsPage.value?.apply {
@@ -65,12 +79,11 @@ class CommentsViewModel : ViewModel() {
 
             nextPage = response.nextpage
             commentsPage.postValue(updatedPage)
-            isLoading = false
         }
     }
 
     fun reset() {
-        isLoading = false
+        isLoading.value = false
         nextPage = null
         commentsPage.value = null
         videoId = null

app/src/main/res/layout/fragment_comments.xml

@@ -1,7 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
-    android:layout_height="match_parent">
+    android:layout_height="match_parent"
+    android:orientation="vertical">
 
     <androidx.recyclerview.widget.RecyclerView
         android:id="@+id/commentsRV"
@@ -15,6 +16,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_gravity="center"
+        android:layout_marginTop="20dp"
         android:visibility="gone" />
 
     <TextView
@@ -26,4 +28,4 @@
         android:text="@string/comments_disabled"
         android:visibility="gone" />
 
-</FrameLayout>
+</LinearLayout>