两个碎片之间的通信(Android)

Question

我的应用程序的屏幕分为两个片段（上和下）。上片段是一个问题（QuizFragmentType1），下部片段（QuizFragment）包含一个" next"的按钮，该按钮正在改变上部片段。

如何通过在下部片段中按"下一个"按钮从上部片段中获取数据？

问题在方法checkAnswers()中。当我尝试从QuizFragmentType1获取一些数据时，我不能。例如：

RadioGroup grp = (RadioGroup) getView().findViewById(R.id.radioGroup1);

radioGroup1在QuizFragmentType1的布局中，因此我无法达到它。我显然缺少这两个片段之间的交流。

有什么建议？

这是代码：

较低片段（quizfragment.java）

public class QuizFragment extends BaseFragment implements View.OnClickListener {
List<Question> quesList;
Button butNext;
EditText input_answer;
Question currentQ;
TextView txtQuestion;
RadioButton rda, rdb, rdc;
int score = 0;
int qid = 0;
private GameActivity activity;
int i = 0;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    return inflater.inflate(R.layout.fragment_quiz, container, false);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onViewCreated(view, savedInstanceState);
    butNext = (Button) view.findViewById(R.id.button1);
    butNext.setOnClickListener(this);
    Random r = new Random();
    int Low = 1;
    int High = 3;
    int numb = r.nextInt(High - Low) + Low;
    if (numb == 1) {
        ((GameActivity) getActivity()).addFragment(R.id.game,
                new QuizFragmentType1());
    } else if (numb == 2) {
        ((GameActivity) getActivity()).addFragment(R.id.game,
                new QuizFragmentType2());
    }
}
public void randomQuestionType() {
    if (i < 5) {
        Random r = new Random();
        int Low = 1;
        int High = 3;
        int numb = r.nextInt(High - Low) + Low;
        if (numb == 1) {
            ((GameActivity) getActivity()).addFragment(R.id.game,
                    new QuizFragmentType1());
        } else if (numb == 2) {
            ((GameActivity) getActivity()).addFragment(R.id.game,
                    new QuizFragmentType2());
        }
        i++;
    }
    else {
        ((GameActivity) getActivity()).setupFragment(R.id.game,
                new ResultFragment());
    }
}
public void checkAnswers() {
    RadioGroup grp = (RadioGroup) getView().findViewById(R.id.radioGroup1);
    RadioButton answer = (RadioButton) getView().findViewById(
            grp.getCheckedRadioButtonId());
    String input = ((EditText) getView().findViewById(R.id.userInput))
            .getText().toString();
    if (currentQ.getAnswer().equals(answer.getText())) {
        score++;
        Log.d("score", "Your score" + score);
    } else if (currentQ.getAnswer().equals(input)) {
        score++;
        Log.d("score", "Your score" + score);
        input_answer.getText().clear();
    }
}
public void onClick(View v) {
    randomQuestionType();
}

}

上部片段（quizfragmentType1.java）或（quizfragmenttype2.java）

public class QuizFragmentType1 extends BaseFragment implements SetQuestionView {
static List<Question> quesList;
int qid = 0;
static Question currentQ;
TextView txtQuestion;
RadioButton rda, rdb, rdc;
float help = 0;
private GameActivity activity;
@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    if (this.activity == null)
        this.activity = (GameActivity) activity;
    quesList = Question.getQuestions(this.activity.getCurrentCategory());
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    return inflater.inflate(R.layout.fragment_quiz_type1, container, false);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onViewCreated(view, savedInstanceState);
    Random br = new Random();
    currentQ = quesList.get(br.nextInt(quesList.size()));
    txtQuestion = (TextView) view.findViewById(R.id.textView1);
    rda = (RadioButton) view.findViewById(R.id.radio0);
    rdb = (RadioButton) view.findViewById(R.id.radio1);
    rdc = (RadioButton) view.findViewById(R.id.radio2);
    setQuestionView();
    for (int i = 0; i < quesList.size(); i++) {
        Log.d("Debug", "Pitanje " + i + ": "
                + quesList.get(i).getQuestion());
    }
}
public void setQuestionView() {
    txtQuestion.setText(currentQ.getQuestion());
    rda.setText(currentQ.getOptA());
    rdb.setText(currentQ.getOptB());
    rdc.setText(currentQ.getOptC());
    qid++;
}

}

Answer 1

您可以做的唯一方法是创建一个LocalBroadcastManager，可以处理所有应用程序组件的communication（互动）的类，即活动，片段，服务等。一旦您的Fragment已经注册了LocalBroadcastManager，它可以与您的自定义IntentFilter通信。您无需在清单中注册它，只需在课堂中注册它，您需要从其他组件中接收信息。

从发送者类中，请致电：

Intent intent = new Intent("custom-event-name");
intent.putExtra("key", dataToBePassed);// may boolean, String, int, etc.
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);

从接收器中，将其注册在onCreate()方法中：

LocalBroadcastManager.getInstance(context).registerReceiver(mMessageReceiver,
      new IntentFilter("custom-event-name"));

另外，请确保您需要在onDestroy()方法中取消注册：

LocalBroadcastManager.getInstance(context).unregisterReceiver(mMessageReceiver);

从接收器片段类获取信息：

private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        String message = intent.getStringExtra("key");
        Log.d("receiver", "Got message: " + message);
      }
    };

注意：如果您在Fragment上注册，则使用getActivity()更改context。如果在Activity上，用this更改。

有关更多示例，请参见此帖子。