src: add isSaved parameter to LobstersItem

Signed-off-by: Aditya Wasan <adityawasan55@gmail.com>

app/src/main/java/dev/msfjarvis/lobsters/data/remote/LobstersPagingSource.kt

@@ -1,24 +1,18 @@
 package dev.msfjarvis.lobsters.data.remote
 
-import android.util.Log
 import androidx.paging.PagingSource
 import dev.msfjarvis.lobsters.data.api.LobstersApi
 import dev.msfjarvis.lobsters.data.local.LobstersPost
-import dev.msfjarvis.lobsters.data.repo.LobstersRepository
 import javax.inject.Inject
 
 class LobstersPagingSource @Inject constructor(
   private val lobstersApi: LobstersApi,
-  private val lobstersRepository: LobstersRepository,
 ) : PagingSource<Int, LobstersPost>() {
 
   override suspend fun load(params: LoadParams<Int>): LoadResult<Int, LobstersPost> {
     return try {
       val page = params.key ?: 1
-      val posts = lobstersApi.getHottestPosts(page).map { post ->
-        val isSaved = lobstersRepository.isPostSaved(post.short_id)
-        post.copy(is_saved = isSaved)
-      }
+      val posts = lobstersApi.getHottestPosts(page)
 
       LoadResult.Page(
         data = posts,

app/src/main/java/dev/msfjarvis/lobsters/ui/main/MainActivity.kt

@@ -78,6 +78,7 @@ fun LobstersApp() {
         HottestPosts(
           posts = hottestPosts,
           listState = hottestPostsListState,
+          isPostSaved = viewModel::isPostSaved,
           saveAction = viewModel::toggleSave,
           modifier = Modifier.padding(bottom = innerPadding.bottom),
         )

app/src/main/java/dev/msfjarvis/lobsters/ui/posts/HottestPosts.kt

@@ -3,6 +3,10 @@ package dev.msfjarvis.lobsters.ui.posts
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.paging.LoadState
 import androidx.paging.compose.LazyPagingItems
@@ -14,6 +18,7 @@ import dev.msfjarvis.lobsters.ui.urllauncher.AmbientUrlLauncher
 fun HottestPosts(
   posts: LazyPagingItems<LobstersPost>,
   listState: LazyListState,
+  isPostSaved: (String) -> Boolean,
   modifier: Modifier = Modifier,
   saveAction: (LobstersPost) -> Unit,
 ) {
@@ -28,11 +33,17 @@ fun HottestPosts(
     ) {
       items(posts) { item ->
         if (item != null) {
+          var isSaved by remember(item.short_id) { mutableStateOf(isPostSaved(item.short_id)) }
+
           LobstersItem(
             post = item,
+            isSaved = isSaved,
             onClick = { urlLauncher.launch(item.url.ifEmpty { item.comments_url }) },
             onLongClick = { urlLauncher.launch(item.comments_url) },
-            onSaveButtonClick = { saveAction.invoke(item) },
+            onSaveButtonClick = {
+              isSaved = isSaved.not()
+              saveAction.invoke(item)
+            },
           )
         }
       }

app/src/main/java/dev/msfjarvis/lobsters/ui/posts/LobstersItem.kt

@@ -61,6 +61,7 @@ val TEST_POST = LobstersPost(
 @Composable
 fun LobstersItem(
   post: LobstersPost,
+  isSaved: Boolean,
   onClick: () -> Unit,
   onLongClick: () -> Unit,
   onSaveButtonClick: () -> Unit,
@@ -121,7 +122,7 @@ fun LobstersItem(
           },
       )
       IconResource(
-        resourceId = if (post.is_saved == true) R.drawable.ic_favorite_24px else R.drawable.ic_favorite_border_24px,
+        resourceId = if (isSaved) R.drawable.ic_favorite_24px else R.drawable.ic_favorite_border_24px,
         modifier = Modifier
           .padding(8.dp)
           .clickable(
@@ -167,6 +168,7 @@ fun Preview() {
       items(listOf(TEST_POST, TEST_POST, TEST_POST, TEST_POST, TEST_POST)) { item ->
         LobstersItem(
           post = item,
+          isSaved = false,
           onClick = {},
           onLongClick = {},
           onSaveButtonClick = {},

app/src/main/java/dev/msfjarvis/lobsters/ui/posts/SavedPosts.kt

@@ -26,6 +26,7 @@ fun SavedPosts(
       items(posts) { item ->
         LobstersItem(
           post = item,
+          isSaved = true,
           onClick = { urlLauncher.launch(item.url.ifEmpty { item.comments_url }) },
           onLongClick = { urlLauncher.launch(item.comments_url) },
           onSaveButtonClick = { saveAction.invoke(item) },

app/src/main/java/dev/msfjarvis/lobsters/ui/viewmodel/LobstersViewModel.kt

@@ -6,7 +6,6 @@ import androidx.paging.Pager
 import androidx.paging.PagingConfig
 import androidx.paging.cachedIn
 import dagger.hilt.android.lifecycle.HiltViewModel
-import dev.msfjarvis.lobsters.data.api.LobstersApi
 import dev.msfjarvis.lobsters.data.local.LobstersPost
 import dev.msfjarvis.lobsters.data.remote.LobstersPagingSource
 import dev.msfjarvis.lobsters.data.repo.LobstersRepository
@@ -18,26 +17,23 @@ import javax.inject.Inject
 @HiltViewModel
 class LobstersViewModel @Inject constructor(
   private val lobstersRepository: LobstersRepository,
-  private val lobstersApi: LobstersApi,
+  private val pagingSource: LobstersPagingSource,
 ) : ViewModel() {
-  private lateinit var source: LobstersPagingSource
   private val _savedPosts = MutableStateFlow(lobstersRepository.getAllPostsFromCache())
   val savedPosts = _savedPosts.asStateFlow()
   val posts = Pager(PagingConfig(25)) {
-    source = LobstersPagingSource(lobstersApi, lobstersRepository)
-    source
+    pagingSource
   }.flow.cachedIn(viewModelScope)
 
   fun toggleSave(post: LobstersPost) {
     viewModelScope.launch {
       val isSaved = lobstersRepository.isPostSaved(post.short_id)
       if (isSaved) removeSavedPost(post) else savePost(post)
-      invalidateSource()
     }
   }
 
-  private fun invalidateSource() {
-    source.invalidate()
+  fun isPostSaved(postId: String): Boolean {
+    return lobstersRepository.isPostSaved(postId)
   }
 
   private fun savePost(post: LobstersPost) {