优化

app/src/main/java/io/legado/app/service/HttpReadAloudService.kt

@@ -95,9 +95,9 @@ class HttpReadAloudService : BaseReadAloudService(),
         task = execute {
             clearSpeakCache()
             removeCacheFile()
-            ReadAloud.httpTTS?.let { httpTts ->
+            val httpTts = ReadAloud.httpTTS ?: return@execute
             contentList.forEachIndexed { index, item ->
-                    if (isActive) {
+                ensureActive()
                 val speakText = item.replace(AppPattern.notReadAloudRegex, "")
                 val fileName =
                     md5SpeakFileName(
@@ -112,14 +112,14 @@ class HttpReadAloudService : BaseReadAloudService(),
                         playAudio(fis.fd)
                     }
                 } else if (hasSpeakCache(fileName)) { //缓存文件还在，可能还没下载完
-                            return@let
+                    return@forEachIndexed
                 } else { //没有下载并且没有缓存文件
-                            try {
                     if (speakText.isEmpty()) {
                         ensureActive()
                         createSilentSound(fileName)
-                                    return@let
+                        return@forEachIndexed
                     }
+                    try {
                         createSpeakCache(fileName)
                         val analyzeUrl = AnalyzeUrl(
                             httpTts.url,
@@ -197,8 +197,6 @@ class HttpReadAloudService : BaseReadAloudService(),
             }
         }
     }
-        }
-    }
 
     @Synchronized
     private fun playAudio(fd: FileDescriptor) {