Activity与service的生命周期及其关系

要了解Activtiy与service的生命周期先要了解他们直接各个生命周期是多少，他们之间有是如何联系一起！

Acitvity有7个生命周期，网上很多资料都有：onCreate--onStart---onRuzme---onPause---onStop--onDestory.、onRestart。还有经常用到的两个函数：onSaveInstanceState、、onConfigurationChanged，onRestoreInstanceState在保持页面信息、横竖屏切换（或者配置变更）及恢复页面信息时候调用。

Sevice的生命周期相对简单：onCreate--onStartCommand--onbind--onunbind--onDestory;其中startService的执行顺序是：onCreate--onStartCommand-onDestory。而bindService的执行顺序是：onCreate--onbind--onunbind--onDestory。

好了了解以上的原理我们现在探索一下他们的之间关系是如何：

思路：建立一个Mainctivity来关系他们。创建三个子Activity和两个service，

MainActivity的代码如下：

import android.app.Service;import android.content.Intent;import android.content.res.Configuration;import android.os.IBinder;import android.util.Log;public class Service2 extends Service{@Overridepublic IBinder onBind(Intent intent) {// TODO Auto-generated method stubLog.i("TAG2", "onBind");intent.setClass(this, Activity2.class);startActivity(intent);return null;}@Overridepublic void onCreate() {// TODO Auto-generated method stubsuper.onCreate();Log.i("TAG2", "onCreate");}@Overridepublic int onStartCommand(Intent intent, int flags, int startId) {// TODO Auto-generated method stubLog.i("TAG2", "onStartCommand");intent.setClass(this, Activity2.class);startActivity(intent);return super.onStartCommand(intent, flags, startId);}@Overridepublic void onDestroy() {// TODO Auto-generated method stubLog.i("TAG2", "onDestroy");super.onDestroy();}@Overridepublic void onConfigurationChanged(Configuration newConfig) {// TODO Auto-generated method stubsuper.onConfigurationChanged(newConfig);Log.i("TAG2", "onConfigurationChanged");}@Overridepublic boolean onUnbind(Intent intent) {// TODO Auto-generated method stubLog.i("TAG2", "onUnbind");return super.onUnbind(intent);}}

Activity1的代码：

public class Activity1 extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.activit1);Log.i("TAGActivity1", "onCreate");}@Overrideprotected void onRestoreInstanceState(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onRestoreInstanceState(savedInstanceState);Log.i("TAGActivity1", "onRestoreInstanceState");}@Overrideprotected void onStart() {// TODO Auto-generated method stubsuper.onStart();Log.i("TAGActivity1", "onStart()");}@Overrideprotected void onRestart() {// TODO Auto-generated method stubsuper.onRestart();Log.i("TAGActivity1", " onRestart()");}@Overrideprotected void onResume() {// TODO Auto-generated method stubsuper.onResume();Log.i("TAGActivity1", "onResume()");}@Overrideprotected void onSaveInstanceState(Bundle outState) {// TODO Auto-generated method stubsuper.onSaveInstanceState(outState);Log.i("TAGActivity1", "onSaveInstanceState");}@Overrideprotected void onPause() {// TODO Auto-generated method stubsuper.onPause();Log.i("TAGActivity1", "onPause");}@Overrideprotected void onStop() {// TODO Auto-generated method stubsuper.onStop();Log.i("TAGActivity1", "onStop");}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {// TODO Auto-generated method stubsuper.onActivityResult(requestCode, resultCode, data);Log.i("TAGActivity1", "onActivityResult");}@Overrideprotected void onDestroy() {// TODO Auto-generated method stubsuper.onDestroy();Log.i("TAGActivity1", "onDestroy");}}

Activity2的代码如下：

package com.acivity_service_test1;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.util.Log;public class Activity2 extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.activit2);Log.i("TAGActivity2", "onCreate");}@Overrideprotected void onRestoreInstanceState(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onRestoreInstanceState(savedInstanceState);Log.i("TAGActivity2", "onRestoreInstanceState");}@Overrideprotected void onStart() {// TODO Auto-generated method stubsuper.onStart();Log.i("TAGActivity2", "onStart()");}@Overrideprotected void onRestart() {// TODO Auto-generated method stubsuper.onRestart();Log.i("TAGActivity2", " onRestart()");}@Overrideprotected void onResume() {// TODO Auto-generated method stubsuper.onResume();Log.i("TAGActivity2", "onResume()");}@Overrideprotected void onSaveInstanceState(Bundle outState) {// TODO Auto-generated method stubsuper.onSaveInstanceState(outState);Log.i("TAGActivity2", "onSaveInstanceState");}@Overrideprotected void onPause() {// TODO Auto-generated method stubsuper.onPause();Log.i("TAGActivity2", "onPause");}@Overrideprotected void onStop() {// TODO Auto-generated method stubsuper.onStop();Log.i("TAGActivity2", "onStop");}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {// TODO Auto-generated method stubsuper.onActivityResult(requestCode, resultCode, data);Log.i("TAGActivity2", "onActivityResult");}@Overrideprotected void onDestroy() {// TODO Auto-generated method stubsuper.onDestroy();Log.i("TAGActivity2", "onDestroy");}}

Activity3的代码：

package com.acivity_service_test1;import android.app.Activity;import android.content.Intent;import android.content.res.Configuration;import android.os.Bundle;import android.util.Log;public class Activity3 extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.activit3);Log.i("TAGActivity3", "onCreate");}@Overrideprotected void onRestoreInstanceState(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onRestoreInstanceState(savedInstanceState);Log.i("TAGActivity3", "onRestoreInstanceState");}@Overrideprotected void onStart() {// TODO Auto-generated method stubsuper.onStart();Log.i("TAGActivity3", "onStart()");}@Overrideprotected void onRestart() {// TODO Auto-generated method stubsuper.onRestart();Log.i("TAGActivity3", " onRestart()");}@Overrideprotected void onResume() {// TODO Auto-generated method stubsuper.onResume();Log.i("TAGActivity3", "onResume()");}@Overrideprotected void onSaveInstanceState(Bundle outState) {// TODO Auto-generated method stubsuper.onSaveInstanceState(outState);Log.i("TAGActivity3", "onSaveInstanceState");}@Overrideprotected void onPause() {// TODO Auto-generated method stubsuper.onPause();Log.i("TAGActivity3", "onPause");}@Overrideprotected void onStop() {// TODO Auto-generated method stubsuper.onStop();Log.i("TAGActivity3", "onStop");}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {// TODO Auto-generated method stubsuper.onActivityResult(requestCode, resultCode, data);Log.i("TAGActivity3", "onActivityResult");}@Overrideprotected void onDestroy() {// TODO Auto-generated method stubsuper.onDestroy();Log.i("TAGActivity3", "onDestroy");}@Overridepublic void onConfigurationChanged(Configuration newConfig) {// TODO Auto-generated method stubsuper.onConfigurationChanged(newConfig);Log.i("TAGActivity3", "onConfigurationChanged");}}

Sservice1的代码：

package com.acivity_service_test1;import android.app.Service;import android.content.Intent;import android.content.res.Configuration;import android.os.IBinder;import android.util.Log;public class Service1 extends Service{@Overridepublic IBinder onBind(Intent intent) {// TODO Auto-generated method stubLog.i("TAG1", "onBind");//Log.i("TAG1", intent.getStringExtra("zhongguo"));return null;}@Overridepublic void onCreate() {// TODO Auto-generated method stubsuper.onCreate();Log.i("TAG1", "onCreate");}@Overridepublic int onStartCommand(Intent intent, int flags, int startId) {// TODO Auto-generated method stub//intent=new Intent();//Log.i("TAG1", intent.getStringExtra("zhongguo"));Log.i("TAG1", "onStartCommand");//Log.i("TAG1", intent.getStringExtra("zhongguo"));//intent=new Intent();////if (getPackageName()==null) {//Log.i("TAG1", "package==null");////}else Log.i("TAG1", getPackageName().toString());intent.setClassName(getPackageName(),getPackageName()+"."+ "Activity1");startActivity(intent);//intent.setClass(this, Activity2.class);//startActivity(intent);return super.onStartCommand(intent, flags, startId);}@Overridepublic void onDestroy() {// TODO Auto-generated method stubLog.i("TAG1", "onDestroy");super.onDestroy();}@Overridepublic void onConfigurationChanged(Configuration newConfig) {// TODO Auto-generated method stubsuper.onConfigurationChanged(newConfig);Log.i("TAG1", "onConfigurationChanged");}@Overridepublic boolean onUnbind(Intent intent) {// TODO Auto-generated method stubLog.i("TAG1", "onUnbind");return super.onUnbind(intent);}}

Service2的代码：

package com.acivity_service_test1;import android.app.Service;import android.content.Intent;import android.content.res.Configuration;import android.os.IBinder;import android.util.Log;public class Service2 extends Service{@Overridepublic IBinder onBind(Intent intent) {// TODO Auto-generated method stubLog.i("TAG2", "onBind");intent.setClass(this, Activity2.class);startActivity(intent);return null;}@Overridepublic void onCreate() {// TODO Auto-generated method stubsuper.onCreate();Log.i("TAG2", "onCreate");}@Overridepublic int onStartCommand(Intent intent, int flags, int startId) {// TODO Auto-generated method stubLog.i("TAG2", "onStartCommand");intent.setClass(this, Activity2.class);startActivity(intent);return super.onStartCommand(intent, flags, startId);}@Overridepublic void onDestroy() {// TODO Auto-generated method stubLog.i("TAG2", "onDestroy");super.onDestroy();}@Overridepublic void onConfigurationChanged(Configuration newConfig) {// TODO Auto-generated method stubsuper.onConfigurationChanged(newConfig);Log.i("TAG2", "onConfigurationChanged");}@Overridepublic boolean onUnbind(Intent intent) {// TODO Auto-generated method stubLog.i("TAG2", "onUnbind");return super.onUnbind(intent);}}

启动Activity界面如下：

  

一、研究Activity的生命周期，启动StartActivity

    如果是按返回键Activity销毁

如果是home键

这时候再点击Activity时

如果是横竖屏会生命情况呢？

   在在manifest.xml设置：android:configChanges

如下：

 4.0以上版本需要在mainfest.xml中设置了 android:configChanges="keyboardHidden|orientation|screenSize“。如果是4.0以下的版本的属性设置：android:configChanges="keyboardHidden|orientation“

锁屏和开屏有是什么情况呢，看如下

二、Activity与Service的关系

    Service的启动的有两种一个舍startService一个是bindservice。如果要停止一定要使用stopservice否则service会一直存在，如果service没有被销毁当再次启动时，直接调用onStartCommand方法。后者与启动它的Activity同个生命周期，当启动它的Activity调用onDestory时。程序调用service中的这两个方法onUnbind和onDestory；

还有一种情况是当Activity销毁时没调用onDestory方法而是强制退出销毁，Startservice也是回被销毁。