判断是否第一次登录

package text.xujiajian.asus.com.shaopdemo;import android.content.SharedPreferences;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.util.Log;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        SharedPreferences sp =this.getSharedPreferences("name",MODE_PRIVATE);        boolean isFirst =sp.getBoolean("isFirst",true);        SharedPreferences.Editor  editor=sp.edit();        if(isFirst){            Log.i("", "onCreate: 第一次");            editor.putBoolean("isFirst",false);            editor.commit();        }else {            Log.i("", "onCreate: 第二次");        }    }}