[Don't use] Initial move GalleryPreviewsScene to compose

app/src/main/java/com/hippo/widget/ComposeContentLayout.kt

@@ -3,28 +3,75 @@ package com.hippo.widget
 import android.os.Parcelable
 import androidx.compose.foundation.layout.Box
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.MutableState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateListOf
 import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.saveable.listSaver
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
+import androidx.compose.runtime.snapshots.SnapshotStateList
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import com.hippo.widget.pullrefresh.PullRefreshIndicator
 import com.hippo.widget.pullrefresh.pullRefresh
 import com.hippo.widget.pullrefresh.rememberPullRefreshState
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import moe.tarsin.coroutines.runSuspendCatching
 
 @Composable
 inline fun <reified T : Parcelable> ContentLayout(
-    content: @Composable (Array<T>) -> Unit,
+    state: ContentState<T>,
+    noinline getData: suspend (Int) -> List<T>,
     modifier: Modifier = Modifier,
+    content: @Composable (Array<T>) -> Unit,
 ) {
     var refreshing by rememberSaveable { mutableStateOf(false) }
+    val coroutineScope = rememberCoroutineScope { Dispatchers.IO }
     val refreshState = rememberPullRefreshState(refreshing = refreshing, onRefresh = {
         refreshing = true
+        if (state.startPage == 0) {
+            coroutineScope.launch {
+                val result = runSuspendCatching { getData(0) }.getOrNull()
+                result?.let {
+                    state.data.clear()
+                    state.data.addAll(it)
+                }
+            }.invokeOnCompletion { refreshing = false }
+        } else {
+            TODO()
+        }
     })
-    val data = rememberSaveable { mutableStateListOf<T>() }
-    Box(modifier = modifier.pullRefresh(refreshState)) {
-        content(data.toTypedArray())
-        PullRefreshIndicator(refreshing = refreshing, state = refreshState)
+    Box(modifier = Modifier.pullRefresh(refreshState)) {
+        content(state.data.toTypedArray())
+        PullRefreshIndicator(refreshing = refreshing, state = refreshState, modifier = modifier.align(Alignment.TopCenter))
     }
 }
+
+class ContentState<T>(
+    val data: SnapshotStateList<T>,
+    _startPage: MutableState<Int>,
+    _endPage: MutableState<Int>,
+) {
+    var startPage by _startPage
+    var endPage by _endPage
+}
+
+@Composable
+fun <T> rememberContentState(
+    initialData: List<T>,
+): ContentState<T> {
+    val snapshotStateListSaver = remember {
+        listSaver(
+            save = { it.toList() },
+            restore = { mutableStateListOf<T>().apply { addAll(it) } },
+        )
+    }
+    val data = rememberSaveable(saver = snapshotStateListSaver) { mutableStateListOf<T>().apply { addAll(initialData) } }
+    val startPage = rememberSaveable { mutableStateOf(0) }
+    val endPage = rememberSaveable { mutableStateOf(0) }
+    return remember { ContentState(data, startPage, endPage) }
+}