public class MainActivity extends Activity {	//Log标签	private static final String TAG = "SIGN";	//声明对象	private Button sign;	private TextView show;	private GridView myDate;	//获取本地时间	Time nowTime = new Time();	//一个月内的天数	private int dayMaxNum;	private int year,month,day,ym;	private SignDAO sdao;	//查询结果	private List<String> list = new ArrayList<String>();	private ArrayList<HashMap<String, Object>> sinalist,alisttmp;	@SuppressLint("NewApi")	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.activity_main);		Log.i(TAG, "SIGN is onCreate");				//初始化对象		init();		//初始化数据库信息		initdata();				myDate.setOnItemClickListener(new OnItemClickListener(){			@Override			public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,					long arg3) {				//判断是否已经签到 从服务器获取签到信息				//模拟从本地数据库获取信息				if(day==arg2+1)//只能当天签到				{					sinalist = sdao.findSinInfo("zhangsan",year+"-"+month+"-"+(arg2+1),"0");					if(sinalist.size()>0)					{						Toast.makeText(getApplicationContext(), "已经签过到不能重复签到", 200).show();						Log.d("", "已签到");					}					else					{						//在数据库插入一条数据						sdao.insertSinInfo("zhangsan", "张三", year+"-"+month+"-"+(arg2+1),year+""+month);						initdata();					}				}							}		});	}		/**	 * @param	初始化对象	 */	private void init(){		sign = (Button)this.findViewById(R.id.sign);		show = (TextView)this.findViewById(R.id.show);		myDate = (GridView)this.findViewById(R.id.myDate);		//取本地时间（时间应该从服务器获取）		nowTime.setToNow();		year = nowTime.year;		month = nowTime.month+1;		day = nowTime.monthDay;		show.setText(year+"-"+month+"-"+day);	}	/**	 * @param	初始化数据库信息	 */	private void initdata(){		 sdao = new SignDAO(MainActivity.this);		 sdao.open();		 sinalist = sdao.findSinInfo("zhangsan","",year+""+month);//查询当月已签到的日期		 list.clear();		 dayMaxNum = getCurrentMonthDay();		 for(int i=0;i<dayMaxNum;i++)			{				list.add(i, i+1+"");			}		 myDate.setSelector(new ColorDrawable(Color.TRANSPARENT));		 myDate.setAdapter(new getDayNumAdapter(getApplicationContext()));	}		class getDayNumAdapter extends BaseAdapter{				Context c;		public getDayNumAdapter(Context c)		{			this.c = c;		}		@Override		public int getCount() {			return list.size();		}		@Override		public Object getItem(int position) {			return list.get(position);		}		@Override		public long getItemId(int arg0) {			return 0;		}		@Override		public View getView(int position, View convertView, ViewGroup parent) {			View v = LinearLayout.inflate(c, R.layout.date, null);			TextView txtWeek = (TextView)v.findViewById(R.id.txtWeekDateMB);			TextView txtDay = (TextView)v.findViewById(R.id.txtDayDateMB);			switch (position)			{				case 0:					txtWeek.setText("一");					break;				case 1:					txtWeek.setText("二");					break;				case 2:					txtWeek.setText("三");					break;				case 3:					txtWeek.setText("四");					break;				case 4:					txtWeek.setText("五");					break;				case 5:					txtWeek.setText("六");					break;				case 6:					txtWeek.setText("日");					break;			}			if(position<7)			{				txtWeek.setVisibility(View.VISIBLE);			}			int lstDay = Integer.parseInt(list.get(position));			//标记当前日期			if(day==lstDay)			{				txtDay.setText(list.get(position).toString());				txtDay.setTextColor(Color.RED);			}else				txtDay.setText(list.get(position).toString());			//标记已签到后的背景			for(int i=0;i<sinalist.size();i++)			{				String nowdate = sinalist.get(i).get("sindate").toString();				String[] nowdatearr = nowdate.split("-");				if(lstDay==Integer.parseInt(nowdatearr[2])){					txtDay.setBackgroundColor(Color.BLUE);					++ym;				}				sign.setText("已经签到天数:"+ym);			}			return v;		}			}			//获取当月的 天数 	public  int getCurrentMonthDay() {  		Calendar a = Calendar.getInstance();  		a.set(Calendar.DATE, 1);  		a.roll(Calendar.DATE, -1);  		int maxDate = a.get(Calendar.DATE);  		return maxDate;  	}			}

DBHelper.java

public class DBHelper extends SQLiteOpenHelper {	public DBHelper(Context context) {		super(context, "sign.db", null, 1);	}	/**	 * @param	创建表	 */	@Override	public void onCreate(SQLiteDatabase db) {		String sql="create table sinTB(" +				"sin_id integer primary key autoincrement," +				"userid varchar(20)," +				"usernmae varchar(20)," +				"sindate varchar(20)," +				"yearmonth varchar(20)," +				"nowdate integer" +				")";		db.execSQL(sql);	}	/**	 * @param	数据库版本更新时，会调用此方法	 */	@Override	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {			}}

SignDAO.java

public class SignDAO {	//声明对象	Context context;	SQLiteDatabase db;	DBHelper dbHelper;		public SignDAO(Context context){		this.context = context;	}		/**	 * @param 打开数据库连接	 */	public boolean open(){		dbHelper = new DBHelper(context);		db = dbHelper.getWritableDatabase();		if(db == null){			return false;		}		return true;	}		/**	 * @param	关闭连接	 */	public void close(){		dbHelper.close();	}		/**	 * @param	插入信息	 * @param uid	 * @param name	 * @param date	 * @param ym	 */	public void insertSinInfo(String uid,String name,String date,String month){		String sql="insert into sinTB(userid,usernmae,sindate,yearmonth,nowdate) values(?,?,?,?,?)";		db.execSQL(sql,new Object[]{uid,name,date,month,System.currentTimeMillis()});	}		/**	 * @param	查询信息	 * @param uid	 * @param date	 * @param ym	 * @return	 */	public ArrayList<HashMap<String, Object>> findSinInfo(String uid,String date,String month){		ArrayList<HashMap<String,Object>> alist = new ArrayList<HashMap<String,Object>>();		alist.clear();		HashMap<String, Object> rowMap;		String sql;		try{			if("0".equals(month))			{				sql="select * from sinTB where userid='"+uid+"' and sindate='"+date+"'";			}			else			{				sql="select * from sinTB where userid='"+uid+"' and yearmonth='"+month+"'";			}			Cursor cur = db.rawQuery(sql, null);			cur.moveToFirst();			while(cur.moveToNext()){				rowMap = new HashMap<String, Object>();				rowMap.put("sin_id", cur.getInt(cur.getColumnIndex("sin_id")));				rowMap.put("userid", cur.getString(cur.getColumnIndex("userid")));				rowMap.put("usernmae", cur.getString(cur.getColumnIndex("usernmae")));				rowMap.put("sindate", cur.getString(cur.getColumnIndex("sindate")));				long aa = cur.getLong(cur.getColumnIndex("nowdate"));				SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");				Date now = new Date(aa);				String date1 = format.format(now);				rowMap.put("nowdate", date1);				Log.e("", cur.getString(cur.getColumnIndex("sindate")));				alist.add(rowMap);			}			return alist;		}catch(Exception e){			return alist;		}			}}