Update ReadBookActivity.kt

app/src/main/java/io/legado/app/ui/book/read/ReadBookActivity.kt

@@ -781,10 +781,11 @@ class ReadBookActivity : VMBaseActivity<ReadBookViewModel>(R.layout.activity_boo
                             val query = data.getStringExtra("query")
                             viewModel.openChapter(index)
                             // block until load correct chapter and pages
-                            while (ReadBook.durChapterIndex != index || ReadBook.curTextChapter?.pages == null ){
+                            var pages = ReadBook.curTextChapter?.pages
+                            while (ReadBook.durChapterIndex != index || pages == null ){
                                 delay(100L)
+                                pages = ReadBook.curTextChapter?.pages
                             }
-                            val pages = ReadBook.curTextChapter?.pages
                             val positions = ReadBook.searchResultPositions(pages, indexWithinChapter, query!!)
                             //todo: show selected text
                             val job1 = async(Main){