添加actionbar.setsubtitle后android應用崩潰

Question

我嘗試運行我的應用程序（來自bignerdranch），添加以下代碼后無法運行它：

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { ActionBar actionBar = getActionBar(); actionBar.setSubtitle("Bodies of Water"); }

我得到一個運行時異常。 如果我刪除這些行，則該應用程序運行正常。 當然我加了@TargetApi（11）

我嘗試更改目標SDK，嘗試復制其他人的代碼。 沒用！！

這是我的代碼：

private void updateQuestion() {

    int question = mQuestionBank[mCurrentIndex].getQuestion();
    mQuestionTextView.setText(question);
}

private void checkAnswer(boolean userPressedTrue) {
    boolean answerIsTrue = mQuestionBank[mCurrentIndex].isTrueQuestion();
    int messageResId = 0;

    if (mIsCheater[mCurrentIndex]) {
        messageResId = R.string.judgment_toast;
    } else {
        if (userPressedTrue == answerIsTrue) {
            messageResId = R.string.correct_toast;
        } else {
            messageResId = R.string.incorrect_toast;
        }
    }
    Toast.makeText(this, messageResId, Toast.LENGTH_SHORT).show();
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (data == null) {
        return;
    }
    mIsCheater[mCurrentIndex] = data.getBooleanExtra(
            CheatActivity.EXTRA_ANSWER_SHOWN, false);
}

@TargetApi(11)
@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    Log.d(TAG, "onCreate(Bundle) called");
    setContentView(R.layout.activity_quiz);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
        ActionBar actionBar = getActionBar();
        actionBar.setSubtitle("Bodies of Water");
    }
    mQuestionTextView = (TextView) findViewById(R.id.question_text_view);

    mTrueButton = (Button) findViewById(R.id.true_button);
    mTrueButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            checkAnswer(true);

        }
    });

    mFalseButton = (Button) findViewById(R.id.false_button);
    mFalseButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            checkAnswer(false);

        }
    }

    );

    mNextButton = (Button) findViewById(R.id.next_button);
    mNextButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            mCurrentIndex = (mCurrentIndex + 1) % mQuestionBank.length;
            // mIsCheater=false;
            updateQuestion();

        }
    });

    if (savedInstanceState != null) {
        mCurrentIndex = savedInstanceState.getInt(KEY_INDEX, 0);
        mIsCheater[mCurrentIndex] = savedInstanceState.getBoolean(CHEATED);
    }

    mCheatButton = (Button) findViewById(R.id.cheat_button);
    mCheatButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            Intent i = new Intent(QuizActivity.this, CheatActivity.class);
            boolean answerIsTrue = mQuestionBank[mCurrentIndex]
                    .isTrueQuestion();
            i.putExtra(CheatActivity.EXTRA_ANSWER_IS_TRUE, answerIsTrue);
            startActivityForResult(i, 0);
        }
    });
    updateQuestion();

}

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
    super.onSaveInstanceState(savedInstanceState);
    Log.i(TAG, "onSaveInstanceState");
    savedInstanceState.putInt(KEY_INDEX, mCurrentIndex);
    savedInstanceState.putBoolean(CHEATED, mIsCheater[mCurrentIndex]);
}

@Override
public void onStart() {
    super.onStart();
    Log.d(TAG, "onStart() called");
}

@Override
public void onPause() {
    super.onPause();
    Log.d(TAG, "onPause() called");
}

@Override
public void onResume() {
    super.onResume();
    Log.d(TAG, "onResume() called");
}

@Override
public void onStop() {
    super.onStop();
    Log.d(TAG, "onStop() called");
}

@Override
public void onDestroy() {
    super.onDestroy();
    Log.d(TAG, "onDestroy() called");
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.quiz, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

}`

可能是什么問題呢？

請幫我..

Answer 1

我在bignerdranch上遇到了同樣的問題。 似乎因為QuizActivity是ActionBarActivity的子類而不是Activity，所以我必須使用getSupportActionBar（）而不是getActionBar（）