Android签到功能的实现

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.text.format.Time;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class myrmbmanage extends Activity {

//定义共享优先数据及基础字段
private String MY_RMBCost ="MY_RMBCost";

private String TodayTime ="TodayTime";

public void onCreate(Bundle savedInstanceState ){
super.onCreate(savedInstanceState);
setContentView(R.layout.myrmbmanage);
final Button bt_qiandao = (Button)findViewById(R.id.bt_qiandao);
final TextView tv_time = (TextView)findViewById(R.id.tv_qiandaotime);

//读取共享数据
SharedPreferences my_rmb_data = getSharedPreferences(MY_RMBCost, 0);

Time t = new Time();
t.setToNow();
int lastmonth = t.month + 1 ;
final String str =  t.year + "年" + lastmonth + "月" + t.monthDay + "日";

final String nowtime =my_rmb_data.getString(TodayTime, "").toString();

if(nowtime.equals(str)==true)
{
tv_time.setText("日期："+ nowtime +"已签到！");
bt_qiandao.setBackgroundResource(R.drawable.yqd);
}
else
{
tv_time.setText("日期："+ str);
bt_qiandao.setBackgroundResource(R.drawable.qd);
}

//签到功能
bt_qiandao.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
// TODO Auto-generated method stub
SharedPreferences my_rmb_data = getSharedPreferences(MY_RMBCost, 0);
if(my_rmb_data.getString(TodayTime, "").toString().equals(str)==true)
{
Toast.makeText( myrmbmanage.this , "今日已签到！", Toast.LENGTH_SHORT).show();
}
else
{
my_rmb_data.edit()
.putString(TodayTime, str)
.commit();
tv_time.setText("日期："+ str +"已签到！");
bt_qiandao.setBackgroundResource(R.drawable.yqd);
Toast.makeText( myrmbmanage.this , "签到成功！", Toast.LENGTH_SHORT).show();
}
}
});

}
}