feat: 优化代码

app/src/main/java/io/legado/app/ui/book/search/DiffCallBack.kt

@@ -49,31 +49,33 @@ class DiffCallBack(private val oldItems: List<SearchBook>, private val newItems:
     }
 
     override fun getChangePayload(oldItemPosition: Int, newItemPosition: Int): Any? {
+        val oldItem = oldItems[oldItemPosition]
+        val newItem = newItems[newItemPosition]
         val payload = Bundle()
-        val newItem = newItems.getOrNull(newItemPosition)
-        val oldItem = oldItems.getOrNull(oldItemPosition)
-        if (newItem == null) return payload
-        if (oldItem?.name != newItem.name) {
+        if (oldItem.name != newItem.name) {
             payload.putString("name", newItem.name)
         }
-        if (oldItem?.author != newItem.author) {
+        if (oldItem.author != newItem.author) {
             payload.putString("author", newItem.author)
         }
-        if (oldItem?.origins?.size != newItem.origins.size) {
+        if (oldItem.origins.size != newItem.origins.size) {
             payload.putInt("origins", newItem.origins.size)
         }
-        if (oldItem?.coverUrl != newItem.coverUrl) {
+        if (oldItem.coverUrl != newItem.coverUrl) {
             payload.putString("cover", newItem.coverUrl)
         }
-        if (oldItem?.kind != newItem.kind) {
+        if (oldItem.kind != newItem.kind) {
             payload.putString("kind", newItem.kind)
         }
-        if (oldItem?.latestChapterTitle != newItem.latestChapterTitle) {
+        if (oldItem.latestChapterTitle != newItem.latestChapterTitle) {
             payload.putString("last", newItem.latestChapterTitle)
         }
-        if (oldItem?.intro != newItem.intro) {
+        if (oldItem.intro != newItem.intro) {
             payload.putString("intro", newItem.intro)
         }
+        if (payload.isEmpty) {
+            return null
+        }
         return payload
     }
 }

app/src/main/java/io/legado/app/ui/book/search/SearchViewModel.kt

@@ -55,7 +55,7 @@ class SearchViewModel(application: Application) : BaseViewModel(application) {
                 WebBook(item).searchBook(
                     searchKey,
                     searchPage,
-                    scope = this@execute,
+                        scope = this,
                     context = searchPool
                 )
                     .timeout(30000L)