我的列表视图项：Easy Medium Hard。 我怎么去禁用中等硬度？ 。以及如何在之后启用它 在“简单”测验中达到一定分数。请帮帮我们。 ：（
这是我的代码。
String classes[] = {"Easy", "Medium", "Hard" };
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, classes));
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
// TODO Auto-generated method stub
super.onListItemClick(l, v, position, id);
String easy = classes[position];
try{
Class openClass = Class.forName("first.project." + easy);
Intent openIntent = new Intent(this , openClass);
startActivity(openIntent);
}
catch (ClassNotFoundException e){
e.printStackTrace();
}
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
finish();
}
}
这是我的QuestionActivity上的代码
public class QuestionActivity extends Activity {
// Called when the activity is first created.
EditText question = null;
RadioButton answer1 = null;
RadioButton answer2 = null;
RadioButton answer3 = null;
RadioButton answer4 = null;
RadioGroup answers = null;
Button finish = null;
int selectedAnswer = -1;
int quesIndex = 0;
int numEvents = 0;
int selected[] = null;
int correctAns[] = null;
boolean review =false;
Button prev, next = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.question);
TableLayout quizLayout = (TableLayout) findViewById(R.id.quizLayout);
quizLayout.setVisibility(android.view.View.INVISIBLE);
try {
question = (EditText) findViewById(R.id.question);
answer1 = (RadioButton) findViewById(R.id.a0);
answer2 = (RadioButton) findViewById(R.id.a1);
answer3 = (RadioButton) findViewById(R.id.a2);
answer4 = (RadioButton) findViewById(R.id.a3);
answers = (RadioGroup) findViewById(R.id.answers);
RadioGroup questionLayout = (RadioGroup)findViewById(R.id.answers);
Button finish = (Button)findViewById(R.id.finish);
finish.setOnClickListener(finishListener);
prev = (Button)findViewById(R.id.Prev);
prev.setOnClickListener(prevListener);
next = (Button)findViewById(R.id.Next);
next.setOnClickListener(nextListener);
selected = new int[Easy.getQuesList().length()];
java.util.Arrays.fill(selected, -1);
correctAns = new int[Easy.getQuesList().length()];
java.util.Arrays.fill(correctAns, -1);
this.showQuestion(0,review);
quizLayout.setVisibility(android.view.View.VISIBLE);
} catch (Exception e) {
Log.e("", e.getMessage().toString(), e.getCause());
}
}
private void showQuestion(int qIndex,boolean review) {
try {
JSONObject aQues = Easy.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.WHITE);
answer2.setTextColor(Color.WHITE);
answer3.setTextColor(Color.WHITE);
answer4.setTextColor(Color.WHITE);
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());
aAns = ansList.getJSONObject(3).getString("Answer");
answer4.setText(aAns.toCharArray(), 0, aAns.length());
Log.d("",selected[qIndex]+"");
if (selected[qIndex] == 0)
answers.check(R.id.a0);
if (selected[qIndex] == 1)
answers.check(R.id.a1);
if (selected[qIndex] == 2)
answers.check(R.id.a2);
if (selected[qIndex] == 3)
answers.check(R.id.a3);
setScoreTitle();
if (quesIndex == (Easy.getQuesList().length()-1))
next.setEnabled(false);
if (quesIndex == 0)
prev.setEnabled(false);
if (quesIndex > 0)
prev.setEnabled(true);
if (quesIndex < (Easy.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 (selected[qIndex] == 3)
answer4.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);
if (correctAns[qIndex] == 3)
answer4.setTextColor(Color.GREEN);
}
} catch (Exception e) {
Log.e(this.getClass().toString(), e.getMessage(), e.getCause());
}
}
private OnClickListener finishListener = new OnClickListener() {
public void onClick(View v) {
setAnswer();
//Calculate Score
int score = 0;
for(int i=0; i<correctAns.length; i++){
if ((correctAns[i] != -1) && (correctAns[i] == selected[i]))
score++;
}
AlertDialog alertDialog;
alertDialog = new AlertDialog.Builder(QuestionActivity.this).create();
alertDialog.setTitle("Score");
alertDialog.setMessage((score) +" out of " + (Easy.getQuesList().length()));
alertDialog.setButton(AlertDialog.BUTTON_NEUTRAL, "Retake", new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int which) {
review = false;
quesIndex=0;
QuestionActivity.this.showQuestion(0, review);
}
});
alertDialog.setButton(AlertDialog.BUTTON_POSITIVE, "Review", new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int which) {
review = true;
quesIndex=0;
QuestionActivity.this.showQuestion(0, review);
}
});
alertDialog.setButton(AlertDialog.BUTTON_NEGATIVE,"Quit", new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int which) {
review = false;
finish();
}
});
alertDialog.show();
}
};
private void setAnswer() {
if (answer1.isChecked())
selected[quesIndex] = 0;
if (answer2.isChecked())
selected[quesIndex] = 1;
if (answer3.isChecked())
selected[quesIndex] = 2;
if (answer4.isChecked())
selected[quesIndex] = 3;
Log.d("",Arrays.toString(selected));
Log.d("",Arrays.toString(correctAns));
}
private OnClickListener nextListener = new OnClickListener() {
public void onClick(View v) {
setAnswer();
quesIndex++;
if (quesIndex >= Easy.getQuesList().length())
quesIndex = Easy.getQuesList().length() - 1;
showQuestion(quesIndex,review);
}
};
private OnClickListener prevListener = new OnClickListener() {
public void onClick(View v) {
setAnswer();
quesIndex--;
if (quesIndex < 0)
quesIndex = 0;
showQuestion(quesIndex,review);
}
};
private void setScoreTitle() {
this.setTitle("Question # " + (quesIndex+1)+ "/" + Easy.getQuesList().length());
}
@Override
public void onBackPressed() {
new AlertDialog.Builder(this)
.setTitle("Warning!!")
.setMessage("Are you sure you want to exit?")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int which) {
finish();
}
})
.setNegativeButton("No", null)
.show();
}
}
答案 0 :(得分：0)
使用如下循环：
int count = adapter.getCount();
for (int i = 0; i < count; i++) {
adapter.remove(adapter.getItem(i));
}
我认为应该有效
XcutionX
答案 1 :(得分：0)
这就是我的理解，你要做的是：
首先，'easy'按钮将被启用，其余两个将被禁用（我猜）。
buttonEasy.setEnabled(true);
buttonMediun.setEnabled(false);
buttonHard.setEnabled(false);
然后在完成“简单”等级的测验后，检查分数是否已达到某个值。如果是，那么您将启用带有代码的“中”按钮：
buttonMedium.setEnabled(true);