增加加载异常处理

app/src/main/java/com/aiosman/ravenow/entity/Loader.kt

@@ -12,7 +12,10 @@ abstract class DataLoader<T,ET> {
     var total by mutableStateOf(0)
     var pageSize by mutableStateOf(10)
     var hasNext by mutableStateOf(true)
+    var isLoading by mutableStateOf(false)
+    var error by mutableStateOf<String?>(null)
     var onListChanged: ((List<T>) -> Unit)? = null
+    var onError: ((String) -> Unit)? = null
     private var firstLoad = true
 
 
@@ -28,7 +31,17 @@ abstract class DataLoader<T,ET> {
             Log.d("DataLoader", "loadData跳过 - 非首次加载")
             return
         }
+        
+        if (isLoading) {
+            Log.d("DataLoader", "loadData跳过 - 正在加载中")
+            return
+        }
+        
         firstLoad = false
+        isLoading = true
+        error = null
+        
+        try {
             Log.d("DataLoader", "调用fetchData - page: $page, pageSize: $pageSize")
             val result = fetchData(page, pageSize, extra)
             list = result.list.toMutableList()
@@ -38,6 +51,14 @@ abstract class DataLoader<T,ET> {
             this.hasNext = result.list.size == pageSize
             Log.d("DataLoader", "loadData完成 - 数据量: ${list.size}, total: $total, hasNext: $hasNext")
             onListChanged?.invoke(list)
+        } catch (e: Exception) {
+            Log.e("DataLoader", "loadData失败", e)
+            error = e.message ?: "加载数据时发生未知错误"
+            firstLoad = true // 重置firstLoad状态，允许重试
+            onError?.invoke(error!!)
+        } finally {
+            isLoading = false
+        }
     }
 
     suspend fun loadMore(extra: ET) {
@@ -49,6 +70,16 @@ abstract class DataLoader<T,ET> {
             Log.d("DataLoader", "loadMore跳过 - hasNext为false")
             return
         }
+        
+        if (isLoading) {
+            Log.d("DataLoader", "loadMore跳过 - 正在加载中")
+            return
+        }
+        
+        isLoading = true
+        error = null
+        
+        try {
             Log.d("DataLoader", "开始loadMore - 当前页: $page, 当前数据量: ${list.size}")
             val result = fetchData(page + 1, pageSize, extra)
             list.addAll(result.list)
@@ -56,6 +87,13 @@ abstract class DataLoader<T,ET> {
             hasNext = result.list.size == pageSize
             Log.d("DataLoader", "loadMore完成 - 新页: $page, 新数据量: ${list.size}, 本次获取: ${result.list.size}, hasNext: $hasNext")
             onListChanged?.invoke(list)
+        } catch (e: Exception) {
+            Log.e("DataLoader", "loadMore失败", e)
+            error = e.message ?: "加载更多数据时发生未知错误"
+            onError?.invoke(error!!)
+        } finally {
+            isLoading = false
+        }
     }
 
     fun clear() {
@@ -65,5 +103,7 @@ abstract class DataLoader<T,ET> {
         pageSize = 10
         hasNext = true
         firstLoad = true
+        isLoading = false
+        error = null
     }
 }