我对 Fragments 和 ViewPager 很陌生。我正在使用 Jack Wharton 的 ActionBarSherlock 和 ViewPageIndicator。
我从一个标准的 Android MasterDetailFlow Activity 开始，并尝试修改它以在细节部分使用 ViewPager。
我正在使用标准的 DummyContent 来提供一些静态数据，但我已将 DummyItem 替换为我必须在此应用程序中使用的“调查”库。DummyContent 提供了一个公共静态 ArrayList，我用它来填充列表活动中的列表。在我在此列表中选择一项调查后，相应的问题应显示在视图寻呼机中。
这是托管问题片段的 QuestionActivity.java 的代码。
public class QuestionActivity extends SherlockFragmentActivity {
private QuestionsFragmentPagerAdapter mAdapter;
private PageIndicator mIndicator;
private ViewPager mPager;
private String surveyName;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_viewpager);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
surveyName = getIntent().getExtras().getString(ItemDetailFragment.ARG_SURVEY_NAME);
mAdapter = new QuestionsFragmentPagerAdapter(getSupportFragmentManager(), DummyContent.mgr.getSurvey(surveyName).getQuestions());
mPager = (ViewPager) findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
mIndicator = (PageIndicator) findViewById(R.id.indicator);
mIndicator.setViewPager(mPager);
}
}
问题FragmentPagerAdapter.java
public class QuestionsFragmentPagerAdapter extends FragmentPagerAdapter {
ArrayList<Question> questions;
public QuestionsFragmentPagerAdapter(FragmentManager fm, List<Question> questions) {
super(fm);
this.questions = (ArrayList<Question>) questions;
}
@Override
public Fragment getItem(int position) {
Fragment f = QuestionFragment.newInstance(questions.get(position));
return f;
}
@Override
public int getCount() {
return questions.size();
}
}
QuestionFragment.java
public class QuestionFragment extends SherlockListFragment {
protected enum QuestionType {
FT, SC, MC;
}
public final static String ARG_QUESTION_QUESTION = "question_question";
public final static String ARG_QUESTION_TYPE = "question_type";
public final static String ARG_QUESTION_ANSWERINGOPTIONS = "question_answeringptions";
private TextView lblQuestion;
private EditText txtAnswer;
private ListView listAnswers;
private ArrayAdapter<String> listAdapter;
private Question question;
private int listLayout;
/**
*
* @param question
* @return
*/
public static QuestionFragment newInstance(Question question) {
QuestionFragment fragment = new QuestionFragment();
// Creates a Bundle with all informations available in the question obj.
Bundle args = createBundleFromQuestion(question);
fragment.setArguments(args);
return fragment;
}
/**
*
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Creates the question object from the given arguments.
// I know this isn't a good solution, i will implement the
// Parcelable asap i have solved the current issues.
//
createQuestionFromBundle(getArguments());
// String questionXml = getArguments() != null ? getArguments().getString(ARG_QUESTION_XML) : null;
// this.question = (Question) MyXmlSerializer.deserialize(questionXml, Question.class);
}
/**
* Creates a the Question object form the Bundle.
* @param extras
*/
private void createQuestionFromBundle(Bundle extras) {
// Think we don't need it here. The field question gets instantiated.
}
/**
*
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.answer_question, null);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
initWidgets();
setCorrectLayout();
initContent();
}
private void initContent() {
String questionStr = question.getQuestion();
lblQuestion.setText(questionStr);
if(question instanceof FTQuestion) {
} else if (question instanceof ClosedQuestion) {
listAdapter = new ArrayAdapter<String>(getActivity(), listLayout);
List<Answer> answeringOptions = question.getAnswers();
for(Answer answer : answeringOptions) {
listAdapter.add(answer.getAnswer());
}
listAnswers.setAdapter(listAdapter);
}
}
/**
*
*/
private void initWidgets() {
listAnswers = getListView();
lblQuestion = (TextView) getActivity().findViewById(R.id.lblQuestion);
txtAnswer = (EditText) getActivity().findViewById(R.id.txtAnswer);
}
/**
* Sets the FT/SC/MC layout
*/
private void setCorrectLayout() {
if(question instanceof FTQuestion) {
setFtLayout();
} else if (question instanceof SCQuestion) {
setScLayout();
} else if (question instanceof MCQuestion) {
setMcLayout();
}
}
/**
*
*/
private void setFtLayout() {
if(listAnswers.getVisibility()!=ListView.INVISIBLE && listAnswers.getVisibility()!=ListView.GONE) {
listAnswers.setVisibility(ListView.GONE);
}
}
/**
*
*/
private void setScLayout() {
listLayout = R.layout.answer_question_single_choice_list_row;
listAnswers.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
if(txtAnswer.getVisibility() == TextView.VISIBLE) txtAnswer.setVisibility(TextView.GONE);
}
/**
*
*/
private void setMcLayout() {
listLayout = R.layout.answer_question_multiple_choice_list_row;
listAnswers.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
if(txtAnswer.getVisibility() == TextView.VISIBLE) txtAnswer.setVisibility(TextView.GONE);
}
}
在列表中选择正确的调查工作正常，但现在显示的问题完全错误。
实际上现在应该有 3 页，包含 3 个不同的问题。在第一页上应该有一个带有问题的标签“Eine tolle FT Frage？” 在此标签下方是一个 EditText。在第二页上应该有一个带有问题“Eine tolle SC Frage？”的标签。并在带有回答选项的列表下方。在第三页应该有问题“Eine tolle MC Frage？” 以及下面的列表，其中包含与第二页相同的回答选项。
屏幕截图按以下顺序显示页面之间的转换：1 -> 2 -> 3 -> 2 -> 1 -> 2。
你可以看到，它并没有以我上面描述的方式出现。页面的内容在转换过程中也会发生变化。我相信 DummyContent 可能有问题，因为它是静态的？！
如果我创建一个只有一个问题的调查，一切正常......