基于Android实现答题倒计时功能

package com.zking.sun.dao;import android.support.v4.app.Fragment;import android.util.Log;/** * Created by sun on 2017/1/11. */public abstract class LazyFragment extends Fragment {  protected boolean isVisible;  /**   * 在这里实现Fragment数据的缓加载.   * @param isVisibleToUser   */  @Override  public void setUserVisibleHint(boolean isVisibleToUser) {    super.setUserVisibleHint(isVisibleToUser);    if(getUserVisibleHint()) {      //可见时调用      isVisible = true;      onVisible();    } else {      isVisible = false;      onInvisible();    }  }  protected abstract void onVisible();  //protected abstract void lazyLoad();  protected abstract void onInvisible();}

package com.zking.sun.android_06_project;import android.content.Intent;import android.os.Bundle;import android.os.CountDownTimer;import android.os.Handler;import android.support.annotation.Nullable;import android.support.v4.app.Fragment;import android.support.v4.view.ViewPager;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.Button;import android.widget.RadioButton;import android.widget.RadioGroup;import android.widget.TextView;import com.zking.sun.dao.LazyFragment;import com.zking.sun.dao.QusetionDao;import com.zking.sun.entity.QuestionEntity;import java.util.List;import static com.zking.sun.android_06_project.R.id.tv_splash_01;/** * Created by sun on 2016/12/21. */public class FragmentActivity extends LazyFragment {  private ViewPager viewpager_main_01;  private TextView question_fragment_tv;  private RadioButton answer_fragment_01,answer_fragment_02,answer_fragment_03,answer_fragment_04;  private QusetionDao qusetionDao=new QusetionDao();  private int i;  private RadioGroup rg_fragment_qu;  private String right_answer;  private TextView count_fragment_down;  private int SPLASH_DISPLAY_LENGHT = 10000; //延迟多少秒  private TextView tv_splash_01;  private Handler handler = new Handler();  private Runnable runnbale ;  private Intent intent;  private MyCountdownTimer countdowntimer;  private TextView questionR_fragment_tv;  private boolean isPrepared;  public FragmentActivity(){  }  public FragmentActivity(int i){    this.i=i;  }  public int getI() {    return i;  }  public void setI(int i) {    this.i = i;  }  @Nullable  @Override  public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {    View v=inflater.inflate(R.layout.fragment_1,null);    //找到问题和答案的控件     question_fragment_tv = (TextView) v.findViewById(R.id.question_fragment_tv);    questionR_fragment_tv = (TextView) v.findViewById(R.id.questionR_fragment_tv);    questionR_fragment_tv.setVisibility(View.INVISIBLE);    answer_fragment_01 = (RadioButton) v.findViewById(R.id.answer_fragment_01);    answer_fragment_02 = (RadioButton) v.findViewById(R.id.answer_fragment_02);    answer_fragment_03 = (RadioButton) v.findViewById(R.id.answer_fragment_03);    answer_fragment_04 = (RadioButton) v.findViewById(R.id.answer_fragment_04);    rg_fragment_qu = (RadioGroup) v.findViewById(R.id.rg_fragment_qu);    count_fragment_down = (TextView) v.findViewById(R.id.count_fragment_down);    //倒计时    countdowntimer = new MyCountdownTimer(10000, 1000);    //绑定值 获取页面的监听的i 传过来改变    isPrepared = true;    //懒加载    getvalue(this.i);    onVisible();//可见    onInvisible();//不可见    // lazyLoad();    return v;  }  public void getvalue(int i){    //查询数据    /**     * @param context 上下文     * @param name  名字（数据库名），文件名     * @param factory 游标工厂，多数情况：null     * @param version 数据库版本     */    //DBHepler dbHepler=new DBHepler(this,"questions.db",null,1);    List<QuestionEntity> questionEntityList=qusetionDao.findAll(getContext());    right_answer = questionEntityList.get(i).getRight_answer();    questionR_fragment_tv.setText("答案："+right_answer);    /* if (right_answer.equalsIgnoreCase("A")){      right_answer = "answer_fragment_01";    }*/    //将查询出来的数据放到控件里面    question_fragment_tv.setText(questionEntityList.get(i).getQusetion());    answer_fragment_01.setText(questionEntityList.get(i).getAnswera());    answer_fragment_02.setText(questionEntityList.get(i).getAnswerb());    answer_fragment_03.setText(questionEntityList.get(i).getAnswerc());    String this04=questionEntityList.get(i).getAnswerd()+"";    Log.i("answer_fragment_04","_____________"+this04+"_____________");    if(this04.equals("")||this04.equals("null")){      answer_fragment_04.setVisibility(View.INVISIBLE);    }    else{      answer_fragment_04.setText(questionEntityList.get(i).getAnswerd());      answer_fragment_04.setVisibility(View.VISIBLE);    }    //get组设点击事件    rg_fragment_qu.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {      @Override      public void onCheckedChanged(RadioGroup group, int checkedId) {        rg_fragment_qu.setEnabled(false);        int selectRadio = group.getCheckedRadioButtonId();        switch (selectRadio){          case R.id.answer_fragment_01:            // countdowntimer.cancel();            if (right_answer.equalsIgnoreCase("A")){              answer_fragment_01.setBackgroundResource(R.drawable.examtxt_btn_right);            }            else{              answer_fragment_01.setBackgroundResource(R.drawable.examtxt_btn_wrong);              questionR_fragment_tv.setVisibility(View.VISIBLE);            }            answer_fragment_02.setEnabled(false);            answer_fragment_03.setEnabled(false);            answer_fragment_04.setEnabled(false);            break;          case R.id.answer_fragment_02:            //countdowntimer.cancel();            if (right_answer.equalsIgnoreCase("B")){              answer_fragment_02.setBackgroundResource(R.drawable.examtxt_btn_right);            }            else{              answer_fragment_02.setBackgroundResource(R.drawable.examtxt_btn_wrong);              questionR_fragment_tv.setVisibility(View.VISIBLE);            }            answer_fragment_01.setEnabled(false);            answer_fragment_03.setEnabled(false);            answer_fragment_04.setEnabled(false);            break;          case R.id.answer_fragment_03:            //countdowntimer.cancel();            if (right_answer.equalsIgnoreCase("C")){              answer_fragment_03.setBackgroundResource(R.drawable.examtxt_btn_right);            }            else{              answer_fragment_03.setBackgroundResource(R.drawable.examtxt_btn_wrong);              questionR_fragment_tv.setVisibility(View.VISIBLE);            }            answer_fragment_02.setEnabled(false);            answer_fragment_01.setEnabled(false);            answer_fragment_04.setEnabled(false);            break;          case R.id.answer_fragment_04:            //countdowntimer.cancel();            if (right_answer.equalsIgnoreCase("D")){              answer_fragment_04.setBackgroundResource(R.drawable.examtxt_btn_right);            }            else{              answer_fragment_04.setBackgroundResource(R.drawable.examtxt_btn_wrong);              questionR_fragment_tv.setVisibility(View.VISIBLE);            }            answer_fragment_02.setEnabled(false);            answer_fragment_03.setEnabled(false);            answer_fragment_01.setEnabled(false);            break;        }      }    });  }  /**   * Rewrite 'CountDownTimer' method.   *   * @param   *      // 倒计时总数，单位为毫秒。   * @param   *      // 每隔多久调用onTick一次   * @author DaiZhenWei   *   */    protected class MyCountdownTimer extends CountDownTimer {      public MyCountdownTimer(long millisInFuture, long countDownInterval) {        super(millisInFuture, countDownInterval);      }      @Override      public void onTick(long millisUntilFinished) {        count_fragment_down.setText("倒计时: " + millisUntilFinished / 1000);      }      @Override      public void onFinish() {        //count_fragment_down.setText("Turning");        FightActivity.getNext(null);      }    }  //fragment的懒加载 重写  @Override  protected void onVisible() {    //可见的    if(!isPrepared || !isVisible) {      //判断isPrepared和isVisible只要有一个不为true就不往下执行      Log.i("isPrepared",isPrepared+"____________"+isVisible);      return;    }    /**     * 倒计时     */    countdowntimer.start();//开始倒计时    Log.i("isPrepared",this.i+"_______4");  }  @Override  protected void onInvisible() {    //不可见的    if(!isPrepared || isVisible) {      return;    }    Log.i("isPrepared","____________我取消了"+this.i);    countdowntimer.cancel();//将倒计时取消  }/*   //主页面  public void loadUI(Class c){    //启动之后跳著页面//    Intent intent=new Intent(SplashActivity.this,MainActivity.class);    Intent intent=new Intent(FragmentActivity.this.getContext(),c);//    SplashActivity.this.startActivity(intent);//    SplashActivity.this.finish();//Toast.LENGTH_LONG  }*/}