Android：TextToSpeech 不工作

Question

Hi i create one application which is depend on TextToSpeech. When i am trying to run my
application It show the NullPointerException in Logcat. i search lot but didn't find helpful Answer.Here Check my Code on this link and Here is my logcat.

04-10 15:11:37.872: WARN/System.err(2798): java.lang.NullPointerException
04-10 15:11:37.872: WARN/System.err(2798):     at com.example.examguide.ExamAppearingActivity.onCreate(ExamAppearingActivity.java:80)
04-10 15:11:37.872: WARN/System.err(2798):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-10 15:11:37.882: WARN/System.err(2798):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
04-10 15:11:37.882: WARN/System.err(2798):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
04-10 15:11:37.882: WARN/System.err(2798):     at android.app.ActivityThread.access$1500(ActivityThread.java:117)
04-10 15:11:37.882: WARN/System.err(2798):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
04-10 15:11:37.882: WARN/System.err(2798):     at android.os.Handler.dispatchMessage(Handler.java:99)
04-10 15:11:37.882: WARN/System.err(2798):     at android.os.Looper.loop(Looper.java:123)
04-10 15:11:37.882: WARN/System.err(2798):     at android.app.ActivityThread.main(ActivityThread.java:3683)
04-10 15:11:37.882: WARN/System.err(2798):     at java.lang.reflect.Method.invokeNative(Native Method)
04-10 15:11:37.892: WARN/System.err(2798):     at java.lang.reflect.Method.invoke(Method.java:507)
04-10 15:11:37.892: WARN/System.err(2798):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
04-10 15:11:37.892: WARN/System.err(2798):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
04-10 15:11:37.892: WARN/System.err(2798):     at dalvik.system.NativeStart.main(Native Method)

Any help is Appreciated...

Answer 1

you have used this code.

final List<ObjectiveWiseQuestion> QuestionWiseProfile1= db.getOneQuestion(examId); 

but you have not opened db before. So it is getting null. ok write

tts = new TextToSpeech(this, this);

before you use tts object.

Answer 2

The tts object is not initialized. Hence you get a null pointer exception there.