TextToSpeech显示空指针异常？

Question

我正在TextToSpeech上创建一个应用程序.但是当我试图运行时,它会在后续行上抛出异常.

tts.speak(ruleOne, TextToSpeech.QUEUE_ADD, null);

这是我的完整代码供参考
请给我任何提示.我不明白我的代码有什么问题.当我编译我的代码时,所有值都正确传递但当它跳转到tts对象上方时它会命中空指针异常.是什么语法错了？哪个方法首先调用onCreate()或onActivityResult？提前致谢

这是Logcat的内容.

04-10 13:58:34.082: WARN/System.err(19352): java.lang.NullPointerException
04-10 13:58:34.082: WARN/System.err(19352):     at com.example.examguide.ExamRulesActivity.onCreate(ExamRulesActivity.java:60)
04-10 13:58:34.082: WARN/System.err(19352):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-10 13:58:34.092: WARN/System.err(19352):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
04-10 13:58:34.092: WARN/System.err(19352):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
04-10 13:58:34.092: WARN/System.err(19352):     at android.app.ActivityThread.access$1500(ActivityThread.java:117)
04-10 13:58:34.092: WARN/System.err(19352):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
04-10 13:58:34.092: WARN/System.err(19352):     at android.os.Handler.dispatchMessage(Handler.java:99)
04-10 13:58:34.092: WARN/System.err(19352):     at android.os.Looper.loop(Looper.java:123)
04-10 13:58:34.092: WARN/System.err(19352):     at android.app.ActivityThread.main(ActivityThread.java:3683)
04-10 13:58:34.102: WARN/System.err(19352):     at java.lang.reflect.Method.invokeNative(Native Method)
04-10 13:58:34.102: WARN/System.err(19352):     at java.lang.reflect.Method.invoke(Method.java:507)
04-10 13:58:34.102: WARN/System.err(19352):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
04-10 13:58:34.102: WARN/System.err(19352):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
04-10 13:58:34.102: WARN/System.err(19352):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

写

tts = new TextToSpeech(this, this);

在onCreate()方法的if循环中.