Activity生命周期

Activity生命周期相关知识，以及在各个生命阶段都发生哪些事情.

首先上代码

package com.example.activitythelifecycle;


import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;


public class MainActivity extends Activity {



/**
* 首先执行的是onPause onStop onDestroy 因为开始屏幕是锁屏状态 Activity没有呈现出来 所以就执行的这三个方法
* 回到桌面是实行了onPause onStop 重新回到Activity 执行的函数是 onRestart onStart onResume
* 按下后退键 执行的函数是 onPause onStop onDestroy再次返回Activity就会执行全新的onCreate onStart onResume
* 
*/
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
System.out.println("oncreate");
}


@Override
protected void onStart() {
// TODO Auto-generated method stub
super.onStart();
System.out.println("onStart");
}


@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
System.out.println("onResume");
}


@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
System.out.println("onPause");
}


@Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
System.out.println("onStop");
}


@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
System.out.println("onDestroy");
}


@Override
protected void onRestart() {
// TODO Auto-generated method stub
super.onRestart();
System.out.println("onRestart");
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}


}

初学者可以对着上面的代码进行学习了解