文章目录
点击获取每日答题完整布局
从每日答题代码做出以下修改
一、数据库存储题目信息
题目信息数据库存储，并从数据库中读取题目信息
1、案例演示
将题目信息存储到android自带数据库中
从中随机取5道题，从运行结果可以看出题目类型是随机的
2、实现步骤
2.1、MyDataBaseHepler.java
该类用于创建数据表questions，表结构如下
public class MyDataBaseHepler extends SQLiteOpenHelper {
public static final String CREATE_QUESTIONS="create table questions(" +
"id integer primary key autoincrement," +
"questionstem text," +
"optionA text," +
"optionB text," +
"optionC text," +
"optionD text," +
"correctOptions text," +
"type integer)";
private Context text;
public MyDataBaseHepler(@Nullable Context context, @Nullable String name, @Nullable SQLiteDatabase.CursorFactory factory, int version) {
super(context, name, factory, version);
text=context;
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_QUESTIONS);
Toast.makeText(text, "创建数据库成功", Toast.LENGTH_SHORT).show();
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
2.2、QuestionsDao.java
数据库操作类用于数据的插入和查询，加查询结果用游标遍历出来存到集合中
public class QuestionsDao {
private MyDataBaseHepler hepler;
public QuestionsDao(Context context){
hepler=new MyDataBaseHepler(context,"question",null,1);
}
//添加数据
public long insertQuestion(Question question){
SQLiteDatabase database=hepler.getWritableDatabase();
ContentValues values=new ContentValues();
String options[] =question.getOptions();
values.put("questionStem",question.getQuestionStem());
values.put("optionA",options[0]);
values.put("optionB",options[1]);
values.put("optionC",options[2]);
values.put("optionD",options[3]);
values.put("correctOptions",question.getCorrectOptions());
values.put("type",question.getQuestionTypes());
long i=database.insert("questions",null,values);
database.close();
return i;
}
//随机查询五道题
public ArrayList queryFive(){
SQLiteDatabase database=hepler.getWritableDatabase();
ArrayList list=new ArrayList();
String sql="select * from questions order by random() limit 5";
Cursor cursor=database.rawQuery(sql,null);
list=convertCursor(cursor);
return list;
}
public ArrayList convertCursor(Cursor cursor){
ArrayList list=new ArrayList();
if (cursor!=null&&cursor.moveToFirst()){
do {
Question question=new Question();
question.setQuestionStem(cursor.getString(1));
String options[]=new String[]{
cursor.getString(cursor.getColumnIndex("optionA")),
cursor.getString(cursor.getColumnIndex("optionB")),
cursor.getString(cursor.getColumnIndex("optionC")),
cursor.getString(cursor.getColumnIndex("optionD"))};
question.setOptions(options);
question.setCorrectOptions(cursor.getString(cursor.getColumnIndex("correctOptions")));
question.setQuestionTypes(cursor.getInt(cursor.getColumnIndex("type")));
list.add(question);
}while (cursor.moveToNext());
}
return list;
}
}
2.3、QuestionActivity.java
改写initQuestions()方法，为了区分是否是第一次调用，我们用SharedPreferences存储一个布尔类型的变量，开始该变量值为true，当第一次调用结束，即数据插入一次后，该变量为false，第二次调用直接进行查询调用数据
- 这里我们插入了7条题目
- 存储布尔类型的变量is
- 统一选项个数为4个
public void initQuestions(){
Log.e("信息更新", "执行了");
QuestionsDao dao=new QuestionsDao(this);
//读取is值
SharedPreferences spf=getPreferences(MODE_PRIVATE);
boolean is=spf.getBoolean("is",true);
if(is){
SharedPreferences.Editor editor=spf.edit();
editor.putBoolean("is",false);
editor.commit();
Question question=new Question();
//题干
question.setQuestionStem("1、哪个季节天气最热？");
//选项
question.setOptions(new String[]{"春","夏","秋","冬"});
//正确的答案
question.setCorrectOptions("1");
//题目类型
question.setQuestionTypes(1);
//把题目添加到集合中
questions.add(question);
Question question2=new Question();
//题干
question2.setQuestionStem("2、坤坤喜欢的运动是什么？");
//选项
question2.setOptions(new String[]{"唱","跳","rap","篮球"});
//正确的答案
question2.setCorrectOptions("1,2");
//题目类型
question2.setQuestionTypes(2);
//把题目添加到集合中
questions.add(question2);
Question question3=new Question();
//题干
question3.setQuestionStem("3、属于前端的是？");
//选项
question3.setOptions(new String[]{"html","css","java","mysql"});
//正确的答案
question3.setCorrectOptions("0,1");
//题目类型
question3.setQuestionTypes(2);
//把题目添加到集合中
questions.add(question3);
Question question4=new Question();
//题干
question4.setQuestionStem("4、属于后端的是？");
//选项
question4.setOptions(new String[]{"java","c","ppt","world"});
//正确的答案
question4.setCorrectOptions("0,1");
//题目类型
question4.setQuestionTypes(2);
//把题目添加到集合中
questions.add(question4);
Question question5=new Question();
//题干
question5.setQuestionStem("5、我使用的手机品牌是？");
//选项
question5.setOptions(new String[]{"苹果","化为","OPPO","VIVO"});
//正确的答案
question5.setCorrectOptions("3");
//题目类型
question5.setQuestionTypes(1);
//把题目添加到集合中
questions.add(question5);
Question question6=new Question();
//题干
question6.setQuestionStem("6、草帽海贼团？");
//选项
question6.setOptions(new String[]{"路飞","娜美","山治","索隆"});
//正确的答案
question6.setCorrectOptions("0,1,2,3");
//题目类型
question6.setQuestionTypes(2);
//把题目添加到集合中
questions.add(question6);
Question question7=new Question();
//题干
question7.setQuestionStem("7、你喜欢的单词？");
//选项
question7.setOptions(new String[]{"apple","food","ate","good"});
//正确的答案
question7.setCorrectOptions("3");
//题目类型
question7.setQuestionTypes(1);
//把题目添加到集合中
questions.add(question7);
dao.insertQuestion(question);
dao.insertQuestion(question2);
dao.insertQuestion(question3);
dao.insertQuestion(question4);
dao.insertQuestion(question5);
dao.insertQuestion(question6);
dao.insertQuestion(question7);
}
questions=dao.queryFive();
}
二、倒计时功能实现
1、案例演示
时间结束返回答题结束窗口
2、实现步骤
2.1、QuestionsDao.java
public class QuestionActivity extends AppCompatActivity {
private TextView time;
private int myTime=2*60;
private Handler handler=new Handler(){
@Override
public void handleMessage(@NonNull Message msg) {
switch (msg.what){
case 0:
showDialog();
break;
case 1:
int minute=msg.arg1;
int second=msg.arg2;
time.setText("剩余时间"+minute+":"+second);
break;
default:
}
}
};
private class ThreadRunnable implements Runnable{
@Override
public void run() {
myTime--;
if (myTime==0){
Message message=new Message();
message.what=0;//代表倒计时结束
handler.sendMessage(message);//发送消息
}else {
Message message=new Message();
message.what=1;
message.arg1=myTime/60;
message.arg2=myTime%60;
handler.sendMessage(message);
handler.postDelayed(this,1000);
}
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_question);
ThreadRunnable runnable=new ThreadRunnable();
runnable.run();
}
}