android: add swipe refresh

android/build.gradle.kts

@@ -13,6 +13,7 @@ dependencies {
   implementation(projects.api)
   implementation(projects.common)
   implementation(libs.accompanist.insets)
+  implementation(libs.accompanist.swiperefresh)
   implementation(libs.accompanist.sysuicontroller)
   implementation(libs.androidx.activity.compose)
   implementation(libs.androidx.appcompat)

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/LobstersApp.kt

@@ -4,15 +4,12 @@ import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.size
-import androidx.compose.material.CircularProgressIndicator
 import androidx.compose.material.MaterialTheme
 import androidx.compose.material.Scaffold
 import androidx.compose.material.primarySurface
 import androidx.compose.material.rememberScaffoldState
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.SideEffect
-import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
@@ -20,6 +17,8 @@ import androidx.paging.LoadState
 import androidx.paging.compose.collectAsLazyPagingItems
 import com.google.accompanist.insets.ProvideWindowInsets
 import com.google.accompanist.insets.statusBarsPadding
+import com.google.accompanist.swiperefresh.SwipeRefresh
+import com.google.accompanist.swiperefresh.rememberSwipeRefreshState
 import com.google.accompanist.systemuicontroller.rememberSystemUiController
 import dev.msfjarvis.claw.android.viewmodel.ClawViewModel
 import dev.msfjarvis.claw.common.theme.LobstersTheme
@@ -46,20 +45,19 @@ fun LobstersApp(
         topBar = { ClawAppBar(modifier = Modifier.statusBarsPadding()) },
         modifier = Modifier,
       ) {
-        if (items.loadState.refresh != LoadState.Loading) {
+        val isRefreshing = items.loadState.refresh == LoadState.Loading
+        SwipeRefresh(
+          state = rememberSwipeRefreshState(isRefreshing),
+          onRefresh = viewModel::reloadPosts,
+        ) {
+          if (items.itemCount == 0) {
+            Box(modifier = Modifier.fillMaxSize())
+          } else {
             NetworkPosts(
               items = items,
               launchUrl = urlLauncher::launch,
               modifier = Modifier.padding(top = 16.dp),
             )
-        } else {
-          Box(
-            modifier = Modifier.fillMaxSize(),
-          ) {
-            CircularProgressIndicator(
-              modifier = Modifier.size(64.dp).align(Alignment.Center),
-              color = MaterialTheme.colors.secondary,
-            )
           }
         }
       }

android/src/main/kotlin/dev/msfjarvis/claw/android/ui/NetworkPosts.kt

@@ -10,7 +10,6 @@ import androidx.paging.compose.items
 import dev.msfjarvis.claw.android.ext.toDbModel
 import dev.msfjarvis.claw.api.model.LobstersPost
 import dev.msfjarvis.claw.common.posts.LobstersCard
-import dev.msfjarvis.claw.common.urllauncher.UrlLauncher
 
 @Composable
 fun NetworkPosts(

android/src/main/kotlin/dev/msfjarvis/claw/android/viewmodel/ClawViewModel.kt

@@ -9,11 +9,21 @@ import dev.msfjarvis.claw.api.LobstersApi
 import javax.inject.Inject
 
 @HiltViewModel
-class ClawViewModel @Inject constructor(
+class ClawViewModel
+@Inject
+constructor(
   api: LobstersApi,
 ) : ViewModel() {
-  private val pager = Pager(PagingConfig(20)) { LobstersPagingSource(api::getHottestPosts) }
+  var lastPagingSource: LobstersPagingSource? = null
+  private val pager =
+    Pager(PagingConfig(20)) {
+      LobstersPagingSource(api::getHottestPosts).also { lastPagingSource = it }
+    }
 
   val pagerFlow
     get() = pager.flow
+
+  fun reloadPosts() {
+    lastPagingSource?.invalidate()
+  }
 }

gradle/libs.versions.toml

@@ -14,6 +14,7 @@ kotlin-coroutines-core = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-co
 kotlin-coroutines-jvm = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core-jvm", version.ref = "coroutines" }
 
 accompanist-insets = { module = "com.google.accompanist:accompanist-insets", version.ref = "accompanist" }
+accompanist-swiperefresh = { module = "com.google.accompanist:accompanist-swiperefresh", version.ref = "accompanist" }
 accompanist-sysuicontroller = { module = "com.google.accompanist:accompanist-systemuicontroller", version.ref = "accompanist" }
 
 androidx-activity-compose = "androidx.activity:activity-compose:1.4.0-alpha02"