Activity生命周期

package com.example.myapplication;

import android.support.v7.app.AppCompatActivity;
        import android.os.Bundle;
import android.util.Log;

/*
        *一个activity理解成一个界面
         */
public class MainActivity extends AppCompatActivity {
/*
*当activity第一次启动的时候执行
*/
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //加载一个页面 页面的内容来自于activity_main布局
        setContentView(R.layout.activity_main);
        Log.i("MainActivity","调用oncreate方法");
    }
//页面可见
    @Override
    protected void onStart() {
        super.onStart();
        Log.i("MainActivity","调用onstart方法");
    }
//当Activity获取焦点开始于用户交互时
    @Override
    protected void onResume() {
        super.onResume();
        Log.i("MainActivity","调用onResume方法");
    }
//失去焦点，不可以进行交互
    @Override
    protected void onPause() {
        super.onPause();
        Log.i("MainActivity","调用onPause方法");
    }
//当页面不可见
    @Override
    protected void onStop() {
        super.onStop();
        Log.i("MainActivity","调用onstop方法");

    }
//页面销毁
    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.i("MainActivity","调用onDestroy方法");
    }

    @Override
    protected void onRestart() {
        super.onRestart();
        Log.i("MainActivity","调用onRestart方法");
    }
}