我正在开发一个测验，其中我存储了50个问题，并且我希望每次用户将在测验中随机显示。我可以这样做吗？是否有可能使用json随机化问题？请帮助我..我真的很感谢你的帮助..谢谢。
public class Question1 extends Activity {
Intent menu = null;
BufferedReader bReader = null;
static JSONArray quesList = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.question10);
Thread thread = new Thread() {
public void run() {
try {
Thread.sleep(1 * 1000);
finish();
loadQuestions();
Intent intent = new Intent(Question1.this,
Question2.class);
Question1.this.startActivity(intent);
} catch (Exception e) {
}
}
};
thread.start();
}
private void loadQuestions() throws Exception {
try {
InputStream questions = this.getBaseContext().getResources()
.openRawResource(R.raw.questions);
bReader = new BufferedReader(new InputStreamReader(questions));
StringBuilder quesString = new StringBuilder();
String aJsonLine = null;
while ((aJsonLine = bReader.readLine()) != null) {
quesString.append(aJsonLine);
}
Log.d(this.getClass().toString(), quesString.toString());
JSONObject quesObj = new JSONObject(quesString.toString());
quesList = quesObj.getJSONArray("Questions");
Log.d(this.getClass().getName(),
"Num Questions " + quesList.length());
} catch (Exception e) {
} finally {
try {
bReader.close();
} catch (Exception e) {
Log.e("", e.getMessage().toString(), e.getCause());
}
}
}
public static JSONArray getQuesList(){
return quesList;
}
}
public class Question2 extends Activity {
/** Called when the activity is first created. */
TextView question, items = null;
RadioButton answer1 = null;
RadioButton answer2 = null;
RadioButton answer3 = null;
RadioGroup answers = null;
int selectedAnswer = -1;
int quesIndex = 0;
int numEvents = 0;
int selected[] = null;
int correctAns[] = null;
boolean review = false;
Button next = null;
int score;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.startquiz);
try {
items = (TextView)findViewById(R.id.displayitems);
question = (TextView) findViewById(R.id.displayquestion);
answer1 = (RadioButton) findViewById(R.id.option1);
answer2 = (RadioButton) findViewById(R.id.option2);
answer3 = (RadioButton) findViewById(R.id.option3);
answers = (RadioGroup) findViewById(R.id.QueGroup1);
next = (Button) findViewById(R.id.selected);
next.setOnClickListener(nextListener);
selected = new int[Question1.getQuesList().length()];
java.util.Arrays.fill(selected, -1);
correctAns = new int[Question1.getQuesList().length()];
java.util.Arrays.fill(correctAns, -1);
this.showQuestion(0, review);
} catch (Exception e) {
Log.e("", e.getMessage().toString(), e.getCause());
}
}
private void showQuestion(int qIndex, boolean review) {
try {
JSONObject aQues = Question1.getQuesList().getJSONObject(
qIndex);
String quesValue = aQues.getString("Question");
if (correctAns[qIndex] == -1) {
String correctAnsStr = aQues.getString("CorrectAnswer");
correctAns[qIndex] = Integer.parseInt(correctAnsStr);
}
question.setText(quesValue.toCharArray(), 0, quesValue.length());
answers.check(-1);
answer1.setTextColor(Color.BLACK);
answer2.setTextColor(Color.BLACK);
answer3.setTextColor(Color.BLACK);
JSONArray ansList = aQues.getJSONArray("Answers");
String aAns = ansList.getJSONObject(0).getString("Answer");
answer1.setText(aAns.toCharArray(), 0, aAns.length());
aAns = ansList.getJSONObject(1).getString("Answer");
answer2.setText(aAns.toCharArray(), 0, aAns.length());
aAns = ansList.getJSONObject(2).getString("Answer");
answer3.setText(aAns.toCharArray(), 0, aAns.length());
Log.d("", selected[qIndex] + "");
if (selected[qIndex] == 0)
answers.check(R.id.option1);
if (selected[qIndex] == 1)
answers.check(R.id.option2);
if (selected[qIndex] == 2)
answers.check(R.id.option3);
setText();
if (quesIndex == (Question1.getQuesList().length() - 1))
next.setEnabled(false);
if (quesIndex < (Question1.getQuesList().length() - 1))
next.setEnabled(true);
if (review) {
Log.d("review", selected[qIndex] + "" + correctAns[qIndex]);
;
if (selected[qIndex] != correctAns[qIndex]) {
if (selected[qIndex] == 0)
answer1.setTextColor(Color.RED);
if (selected[qIndex] == 1)
answer2.setTextColor(Color.RED);
if (selected[qIndex] == 2)
answer3.setTextColor(Color.RED);
}
if (correctAns[qIndex] == 0)
answer1.setTextColor(Color.GREEN);
if (correctAns[qIndex] == 1)
answer2.setTextColor(Color.GREEN);
if (correctAns[qIndex] == 2)
answer3.setTextColor(Color.GREEN);
}
} catch (Exception e) {
Log.e(this.getClass().toString(), e.getMessage(), e.getCause());
}
}
private void setAnswer() {
if (answer1.isChecked())
selected[quesIndex] = 0;
if (answer2.isChecked())
selected[quesIndex] = 1;
if (answer3.isChecked())
selected[quesIndex] = 2;
Log.d("", Arrays.toString(selected));
Log.d("", Arrays.toString(correctAns));
}
private OnClickListener nextListener = new OnClickListener() {
public void onClick(View v) {
setAnswer();
for(int i=0; i<correctAns.length; i++){
if ((correctAns[i] != -1) || (correctAns[i] == selected[i]))
{
if (correctAns[i] == selected[i])
score++;
Toast.makeText(getApplicationContext(), "Your answer is correct!", Toast.LENGTH_SHORT).show();
}else
{
Toast.makeText(getApplicationContext(), "Your answer is wrong...", Toast.LENGTH_SHORT).show();
}
quesIndex++;
if (quesIndex >= Question1.getQuesList().length())
//quesIndex = Question1.getQuesList().length() - 1;
showQuestion(quesIndex, review);
}
}
};
private void setText() {
this.setTitle("Question " + (quesIndex + 1) + "out of "
+ Question1.getQuesList().length());
items.setGravity(250);
}
public void reload() {
Intent intent = getIntent();
overridePendingTransition(0, 0);
intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
finish();
overridePendingTransition(0, 0);
startActivity(intent);
}
}
答案 0 :(得分：0)
使用((int) Math.random() * <size of your array>)为您的问题数组生成随机索引