簡(jiǎn)單介紹Activity生命周期經(jīng)常調(diào)用的幾個(gè)方法：

• onCreate()與onDestroy()
  Activity的創(chuàng)建與銷毀瓜富，處于Activity的entire lifetime完整生命周期
• onStart()與onStop()
  Activity的可見與不可見，處于Activity的visible lifetime可見生命周期
• onResume()與onPause()
  Activity的獲取焦點(diǎn)與失去焦點(diǎn),處于Activity的foreground time 前臺(tái)生命周期
• onSaveInstanceState()與onRestoreIntanceState()
  保存數(shù)據(jù)和取出保存的數(shù)據(jù)合溺，橫豎屏切換的時(shí)候毁欣，兩個(gè)方法會(huì)被同時(shí)調(diào)用庇谆，當(dāng)然這只是這兩個(gè)方法同時(shí)出現(xiàn)場(chǎng)景之一
• onConfiguration()
  在Activity的Manifest文件下配置完configChanges屬性,如果是橫豎屏切換相關(guān)值，則在橫豎屏切換時(shí)會(huì)被調(diào)用

下面用Activity的使用的七個(gè)場(chǎng)景來這些生命周期方法的執(zhí)行順序

一凭疮、Activity1首次啟動(dòng)

onCreate-->onStart-->onResume

控制臺(tái)打印效果圖

Activity首次啟動(dòng)生命周期調(diào)用順序.png

二饭耳、Activity1按返回鍵并從手機(jī)緩存應(yīng)用列表中啟動(dòng)

onResume-->onPause-->onStop-->onDestroy
再次啟動(dòng)：onCreate-->onStart-->onResume

控制臺(tái)打印效果圖

Activity從手機(jī)緩存啟動(dòng).jpg

三、Activity1按住home鍵從手機(jī)緩存應(yīng)用列表中再次啟動(dòng)

onResume-->onPause-->onSaveInstanceState-->onStop
再次啟動(dòng):onRestart-->onStart-->onResume

控制臺(tái)打印效果圖

Home鍵再?gòu)氖謾C(jī)緩存啟動(dòng).jpg

四执解、Activity1鎖屏關(guān)閉再開啟

onResume-->onPause-->onSaveInstanceState-->onStop
再次啟動(dòng):onRestart-->onStart-->onResume

控制臺(tái)打印效果圖

鎖屏關(guān)閉.jpg

五寞肖、Activity1啟動(dòng)Activity2

Activity1:onResume-->onPause
Activity2:onCreate-->onStart-->onResume
Activity1:onSaveInstanceState-->onStop

控制臺(tái)打印效果圖

Activity1啟動(dòng)Activity2.jpg

六、Activity1啟動(dòng)Activity2,Activity2退出或者按返回鍵

Activity2:onResume-->onPause
Activity1:onRestart-->onStart-->onResume
Activity2:onStop-->onDestroy

控制臺(tái)打印效果圖

Activity2被關(guān)閉.jpg

七衰腌、Activity1橫縱屏切換新蟆，并做相關(guān)配置

豎屏：onCreate-->onStart-->onResume-->onPause-->onSaveInstanceState
-->onStop-->onDestroy

橫屏：onCreate-->onStart-->onRestoreInstanceState-->onResume

控制臺(tái)打印效果圖

橫縱屏切換.jpg

配置Activity橫豎切換不重新創(chuàng)建

android:configChanges="orientation|screenSize"
是在AndroidManifest.xml相應(yīng)的<activity>標(biāo)簽的屬性

控制臺(tái)打印效果圖

配置ActivityconfigChanges后生命周期.jpg

Activity1代碼塊

public class MainActivity extends AppCompatActivity {
   static String TAG="dayng";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if(savedInstanceState!=null){
            Log.i(TAG,"退出時(shí)保存的數(shù)據(jù)"+savedInstanceState.getString("dayang"));
        }
        Log.i(TAG,"-------MainActivity.onCreate--------");
    }
    public void onClick(View view){
        Intent intent=new Intent(this,Main2Activity.class);
        startActivity(intent);
    }
    @Override
    protected void onStart() {
        super.onStart();
        Log.i(TAG,"-------MainActivity.onStart--------");
    }
    @Override
    protected void onResume() {
        super.onResume();
        Log.i(TAG,"-------MainActivity.onResume--------");
    }
    @Override
    protected void onPause() {
        super.onPause();
        Log.i(TAG,"-------MainActivity.onPause--------");
    }
    @Override
    protected void onRestart() {
        super.onRestart();
        Log.i(TAG,"-------MainActivity.onRestart--------");
    }
    @Override
    protected void onStop() {
        super.onStop();
        Log.i(TAG,"-------MainActivity.onStop--------");
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.i(TAG,"-------MainActivity.onDestroy--------");
    }
    @Override
    protected void onSaveInstanceState(Bundle outState) {
        outState.putString("dayang","-----7777777");
        super.onSaveInstanceState(outState);
        Log.i(TAG,"--------MainActivity.onSaveInstanceState--------");
    }
    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        Log.i(TAG,"--------MainActivity.onRestoreInstanceState--------");
    }
    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        Log.i(TAG,"--------MainActivity.onConfiguration--------");
    }
}

Activity2代碼塊

public class Main2Activity extends AppCompatActivity {
    static String TAG="dayang";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        Log.i(TAG,"-------Main2Activity.onCreate-------");
    }
    @Override
    protected void onStart() {
        super.onStart();
        Log.i(TAG,"-------Main2Activity.onStart-------");
    }
    @Override
    protected void onResume() {
        super.onResume();
        Log.i(TAG,"-------Main2Activity.onResume-------");
    }
    @Override
    protected void onPause() {
        super.onPause();
        Log.i(TAG,"-------Main2Activity.onPause-------");
    }
    @Override
    protected void onStop() {
        super.onStop();
        Log.i(TAG,"-------Main2Activity.onStop-------");
    }
    @Override
    protected void onRestart() {
        super.onRestart();
        Log.i(TAG,"-------Main2Activity.onRestart-------");
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.i(TAG,"-------Main2Activity.onDestroy-------");
    }
    public void close(View view){
        finish();
    }
    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        Log.i(TAG,"-------Main2Activity.onSaveInstanceState-------");
    }
    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        Log.i(TAG,"-------Main2Activity.onRestoreInstanceState-------");
    }
    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        Log.i(TAG,"-------Main2Activity.onConfiguration-------");
    }
}