activity生命周期

来源：互联网发布：歌曲音量增大软件编辑：程序博客网时间：2024/05/16 15:16

前言：activity生命周期一个老生常谈的话题，但是没有亲自动手测试过，每次遇到都不是特别的清晰，处于模糊的装填。故

两个activity main second class 布局在main中添加了两个按钮一个弹出对话框和一个跳转的按钮布局简单不黏贴了

public class MainActivity extends Activity {String TAG = "MainActivity";private AlertDialog.Builder builder;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);builder = new Builder(this);builder.setTitle("title");builder.setMessage("消息");builder.setCancelable(false);Button btn = (Button) this.findViewById(R.id.button);btn.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View arg0) {// TODO Auto-generated method stubbuilder.create().show();}});Button button = (Button) this.findViewById(R.id.tiaozhuan);button.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View arg0) {// TODO Auto-generated method stubstartActivity(new Intent(MainActivity.this,SecondActivity.class));}});}@Overrideprotected void onStart() {// TODO Auto-generated method stubsuper.onStart();Log.e(TAG, "onStart");}@Overrideprotected void onResume() {// TODO Auto-generated method stubsuper.onResume();Log.e(TAG, "onResume");}@Overrideprotected void onPause() {// TODO Auto-generated method stubsuper.onPause();Log.e(TAG, "onPause");}@Overrideprotected void onStop() {// TODO Auto-generated method stubsuper.onStop();Log.e(TAG, "onStop");}@Overrideprotected void onDestroy() {// TODO Auto-generated method stubsuper.onDestroy();Log.e(TAG, "onDestroy");}}

second 代码

package com.example.ceshi;import android.os.Bundle;import android.app.Activity;import android.util.Log;import android.view.Menu;public class SecondActivity extends Activity {String TAG = "SecondActivity";@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_second);Log.e(TAG, "onCreate");}@Overrideprotected void onStart() {// TODO Auto-generated method stubsuper.onStart();Log.e(TAG, "onStart");}@Overrideprotected void onResume() {// TODO Auto-generated method stubsuper.onResume();Log.e(TAG, "onResume");}@Overrideprotected void onPause() {// TODO Auto-generated method stubsuper.onPause();Log.e(TAG, "onPause");}@Overrideprotected void onStop() {// TODO Auto-generated method stubsuper.onStop();Log.e(TAG, "onStop");}@Overrideprotected void onDestroy() {// TODO Auto-generated method stubsuper.onDestroy();Log.e(TAG, "onDestroy");}}

当我们点击弹出对话框的时候是对activity的生命周期没有任何影响的。

当我们点击跳转时候打印如下

07-27 21:36:33.855: E/MainActivity(1848): onPause
07-27 21:36:33.871: E/SecondActivity(1848): onCreate
07-27 21:36:33.871: E/SecondActivity(1848): onStart
07-27 21:36:33.871: E/SecondActivity(1848): onResume
07-27 21:36:34.267: E/MainActivity(1848): onStop

当我们进入第二个activity后按返回按钮打印如下

07-27 21:38:37.119: E/SecondActivity(1848): onPause
07-27 21:38:37.119: E/MainActivity(1848): onStart
07-27 21:38:37.119: E/MainActivity(1848): onResume
07-27 21:38:37.515: E/SecondActivity(1848): onStop
07-27 21:38:37.515: E/SecondActivity(1848): onDestroy

可以看到返回按钮会销毁activity的

当我们在第一个activity直接返回主界面打印如下

07-27 21:40:31.843: E/MainActivity(1848): onPause
07-27 21:40:32.379: E/MainActivity(1848): onStop

再回到主界面

07-27 21:41:08.107: E/MainActivity(1848): onStart
07-27 21:41:08.107: E/MainActivity(1848): onResume

其次但我们进行屏幕切换横竖

系统默认会重新加载即 onpause onstop ondestroy oncreat onstart onresume

虽然勉强初级的了解了整个流程了，但是还要结合到具体的需求中才行，还要继续参透

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