优化

app/src/main/java/io/legado/app/ui/book/remote/RemoteBookActivity.kt

@@ -122,7 +122,13 @@ class RemoteBookActivity : VMBaseActivity<ActivityImportBookBinding, RemoteBookV
         adapter.selected.clear()
         viewModel.loadRemoteBookList(
             viewModel.dirList.lastOrNull()?.path ?: RemoteBookWebDav.rootBookUrl
-        )
+        ) {
+            if (it) {
+                waitDialog.show()
+            } else {
+                waitDialog.dismiss()
+            }
+        }
     }
 
     override fun openDir(remoteBook: RemoteBook) {

app/src/main/java/io/legado/app/ui/book/remote/RemoteBookViewModel.kt

@@ -52,7 +52,7 @@ class RemoteBookViewModel(application: Application): BaseViewModel(application){
         }
     }
 
-    fun loadRemoteBookList(path: String) {
+    fun loadRemoteBookList(path: String, loadCallback: (loading: Boolean) -> Unit) {
         execute {
             dataCallback?.clear()
             val bookList = RemoteBookWebDav.getRemoteBookList(path)
@@ -60,6 +60,10 @@ class RemoteBookViewModel(application: Application): BaseViewModel(application){
         }.onError {
             AppLog.put("获取webDav书籍出错\n${it.localizedMessage}", it)
             context.toastOnUi("获取webDav书籍出错\n${it.localizedMessage}")
+        }.onStart {
+            loadCallback.invoke(true)
+        }.onFinally {
+            loadCallback.invoke(false)
         }
     }