Android之Listview（item为单选题）自定义adapter，像考试时前面的10几道单选题的实现

标签： android自定义listviewitem是单选题 2015-04-22 21:00  517人阅读  评论(2)  收藏  举报   分类： android开发（1） 

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用于展现重复性的东西，Listview比较好用，看了别人的自定义Adapter（item是EditText，能够很好地获取到每一个item的EditText值）。又由于在做项目的需要，故特制了一个item包含RadioGroup的Listview的自定义Adapter。  主要功能：  1.将任意数目的单选题（题干和4个选项）展现在界面上；  2.每一题都选择后，提交，可以讲每一题的答案获取到  涉及到两个entity：

public class TopicItem implements Serializable { private String questionId;//题目id private String question;//题干 private String answerId; private String userAnswerId; //选择的答案选项 private List<OptionItem> optionList; public String getQuestionId() { return questionId; } public void setQuestionId(String questionId) { this.questionId = questionId; } public String getQuestion() { return question; } public void setQuestion(String question) { this.question = question; } public String getAnswerId() { return answerId; } public void setAnswerId(String answerId) { this.answerId = answerId; } public String getUserAnswerId() { return userAnswerId; } public void setUserAnswerId(String userAnswerId) { this.userAnswerId = userAnswerId; } public List<OptionItem> getOptionList() { return optionList; } public void setOptionList(List<OptionItem> optionList) { this.optionList = optionList; } } 1234567891011121314151617181920212223242526272829303132333435363738 1234567891011121314151617181920212223242526272829303132333435363738 public class OptionItem implements Serializable { private String answerOption;//选项序号 private String answer;//选项文字 public String getAnswerOption() { return answerOption; } public void setAnswerOption(String answerOption) { this.answerOption = answerOption; } public String getAnswer() { return answer; } public void setAnswer(String anwer) { this.answer = anwer; } } 12345678910111213141516 12345678910111213141516

自定义的adapter：

public class TopicAdapter extends BaseAdapter { private static final String TAG = "TopicAdapter" ; String KEY = "list_topic_item"; private LayoutInflater mInflater; private Context context; private List<Map<String, TopicItem>> mData; public TopicAdapter(Context context, List<Map<String, TopicItem>> data) { mData = data; mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); this.context = context; init(); } private void init() { mData.clear(); } @Override public int getCount() { int count = mData == null ? 0 : mData.size(); return count ; } @Override public Object getItem(int position) { /*Object obj = records != null && records.size() > position ? records.get(position) : null; return obj;*/ return null; } @Override public long getItemId(int position) { //return position; return 0; } private Integer index = -1; @Override public View getView(final int position, View convertView, ViewGroup parent) { Holder holder = null; if( convertView == null ){ convertView = mInflater.inflate(R.layout.topic_item, null); holder = new Holder() ; holder.question = (TextView)convertView.findViewById(R.id.topic_item_question); holder.option = (RadioGroup) convertView.findViewById(R.id.topic_item_option); holder.option1 = (RadioButton) convertView.findViewById(R.id.topic_item_option1); holder.option2 = (RadioButton) convertView.findViewById(R.id.topic_item_option2); holder.option3 = (RadioButton) convertView.findViewById(R.id.topic_item_option3); holder.option4 = (RadioButton) convertView.findViewById(R.id.topic_item_option4); holder.option.setTag(position); holder.option.setOnTouchListener(new OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { if (event.getAction() == MotionEvent.ACTION_UP) { index = (Integer) v.getTag(); } return false; } }); class MyOnCheckedChangeListener implements RadioGroup.OnCheckedChangeListener { public MyOnCheckedChangeListener(Holder holder) { mHolder = holder; } private Holder mHolder; @Override public void onCheckedChanged(RadioGroup group, int checkedId) { // TODO Auto-generated method stub int position = (Integer) mHolder.option.getTag(); TopicItem item = mData.get(position).get(KEY); int RadioButtonId = mHolder.option.getCheckedRadioButtonId(); group.check(RadioButtonId); RadioButton rb = (RadioButton)mHolder.option.findViewById(RadioButtonId); if(RadioButtonId==mHolder.option1.getId()){ item.setUserAnswerId(item.getOptionList().get(0).getAnswerOption().trim()); }else if(RadioButtonId==mHolder.option2.getId()){ item.setUserAnswerId(item.getOptionList().get(1).getAnswerOption().trim()); }else if(RadioButtonId==mHolder.option3.getId()){ item.setUserAnswerId(item.getOptionList().get(2).getAnswerOption().trim()); }else if(RadioButtonId==mHolder.option4.getId()){ item.setUserAnswerId(item.getOptionList().get(3).getAnswerOption().trim()); } mData.get(position).put(KEY, item); } } holder.option.setOnCheckedChangeListener(new MyOnCheckedChangeListener(holder)); convertView.setTag(holder); }else{ holder = (Holder)convertView.getTag(); holder.option.setTag(position); } TopicItem item = (TopicItem)mData.get(position).get(KEY); if( item != null ){ holder.question.setText(item.getQuestion()); holder.option1.setText(item.getOptionList().get(0).getAnswer().toString()); holder.option2.setText(item.getOptionList().get(1).getAnswer().toString()); holder.option3.setText(item.getOptionList().get(2).getAnswer().toString()); holder.option4.setText(item.getOptionList().get(3).getAnswer().toString()); if(item.getUserAnswerId().trim().equalsIgnoreCase(item.getOptionList().get(0).getAnswerOption().trim())){ holder.option.check(holder.option1.getId()); } else if(item.getUserAnswerId().trim().equalsIgnoreCase(item.getOptionList().get(1).getAnswerOption().trim())){ holder.option.check(holder.option2.getId()); }else if(item.getUserAnswerId().trim().equalsIgnoreCase(item.getOptionList().get(2).getAnswerOption().trim())){ holder.option.check(holder.option3.getId()); }else if(item.getUserAnswerId().trim().equalsIgnoreCase(item.getOptionList().get(3).getAnswerOption().trim())){ holder.option.check(holder.option4.getId()); } } holder.option.clearFocus(); if (index != -1 && index == position) { holder.option.requestFocus(); } return convertView; } private class Holder{ private TextView question; private RadioGroup option; private RadioButton option1; private RadioButton option2; private RadioButton option3; private RadioButton option4; } } 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141

应用步骤：  1.定义一些变量，为后面做准备

//Adapter需要该Activity的context public Context context; private ListView topic_listview; private Button button_sent; private BaseAdapter mAdapter; //需要将题目数据存在Map中，多个Map组成list，并传给Adapter //一道题对应一个Map private List<Map<String, TopicItem>> data = new ArrayList<Map<String, TopicItem>>(); //模拟http获取到的Json类型的数据 JSONObject data_json; //Map存入数据时的key String KEY = "list_topic_item"; 123456789101112 123456789101112

2.初始化题目数据，这里直接本地编了几道题，可以从服务器上获取

private void initData(){ try { data_json = new JSONObject(); data_json.put("result", "success"); JSONArray array = new JSONArray(); for(int i=0;i<3;i++){ JSONObject object = new JSONObject(); object.put("questionId", "1"); object.put("question", "康熙是乾隆的谁？"); object.put("answerId", ""); //一开始选择好第三项 object.put("userAnswerId", "3"); JSONArray sarray = new JSONArray(); JSONObject sobject1 = new JSONObject(); sobject1.put("answerOption", "1"); sobject1.put("answer", "儿子"); sarray.put(sobject1); JSONObject sobject2 = new JSONObject(); sobject2.put("answerOption", "2"); sobject2.put("answer", "爷爷"); sarray.put(sobject2); JSONObject sobject3 = new JSONObject(); sobject3.put("answerOption", "3"); sobject3.put("answer", "父亲"); sarray.put(sobject3); JSONObject sobject4 = new JSONObject(); sobject4.put("answerOption", "4"); sobject4.put("answer", "孙子"); sarray.put(sobject4); object.put("optionList", sarray); array.put(object); } data_json.put("list", array); } catch (JSONException e) { // TODO Auto-generated catch block e.printStackTrace(); } } 1234567891011121314151617181920212223242526272829303132333435363738394041 1234567891011121314151617181920212223242526272829303132333435363738394041

3.将Listview与自定义的TopicAdapter关联起来

this.context = this; //获取Listview topic_listview = (ListView)findViewById(R.id.topic_quest_answer); //data是题目的数据，放在Map里 mAdapter = new TopicAdapter(context, data); topic_listview.setAdapter(mAdapter); 123456 123456

4.将Json中的题目数据解析并放入data，更新给Adapter，这样关联的Listview此时才将数据显示出来

private void getData(){ System.out.println(data_json.toString()); data.clear(); if(data_json.optString("result").equals("success")){ if(data_json.optJSONArray("list")!=null){ for(int i=0;i<data_json.optJSONArray("list").length();i++){ JSONObject object = data_json.optJSONArray("list").optJSONObject(i); TopicItem topic = new TopicItem(); topic.setAnswerId(object.optString("answerId")); topic.setQuestionId(object.optString("questionId")); topic.setQuestion(object.optString("question")); topic.setUserAnswerId(object.optString("userAnswerId")); List<OptionItem> optionList = new ArrayList<OptionItem>(); for(int j=0;j<object.optJSONArray("optionList").length();j++){ JSONObject object_option = object.optJSONArray("optionList").optJSONObject(j); OptionItem option = new OptionItem(); option.setAnswerOption(object_option.optString("answerOption")); option.setAnswer(object_option.optString("answer")); optionList.add(option); } topic.setOptionList(optionList); Map<String, TopicItem> list_item = new HashMap<String, TopicItem>(); list_item.put(KEY, topic); data.add(list_item); } //提醒Adapter更新数据，紧接着Listview显示新的数据 mAdapter.notifyDataSetChanged(); } } } 123456789101112131415161718192021222324252627282930313233343536 123456789101112131415161718192021222324252627282930313233343536

5.用户答题，提交题目的答案时，我们可以看到所有的题目及选择的选项：

button_sent = (Button) findViewById(R.id.topic_sent_comment); button_sent.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { // TODO Auto-generated method stub String t=""; for (int i = 0; i < data.size(); i++) { t = t+"第 "+(i+1)+" 题 ----------->您选择了【选项" +data.get(i).get(KEY).getUserAnswerId().trim()+"】 \n"; } Toast.makeText(context, t, Toast.LENGTH_SHORT).show(); } }); 12345678910111213 12345678910111213

接下来，我们来看具体运行情况：  a.  每一题我设选项都是第三项，object.put(“userAnswerId”, “3”);  b. 接下来人工选择，分别为4,3,2项  c.提交，可以看到提取结果正确