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官方解释： 通过设置这个属性可以使Activity捕捉设备状态变化，以下是可以被识别的内容：
设置方法：将下列字段用“|”符号分隔开，例如：“locale|navigation|orientation”Value Description
“mcc“
The IMSI mobile country code (MCC) has changed — that is, a SIM hasbeen detected and updated the MCC.移动国家号码，由三位数字组成，每个国家都有自己独立的MCC，可以识别手机用户所属国家。“mnc“
The IMSI mobile network code (MNC) has changed — that is, a SIM hasbeen detected and updated the MNC.移动网号，在一个国家或者地区中，用于区分手机用户的服务商。“locale“
The locale has changed — for example, the user has selected a new language that text should be displayed in.用户所在地区发生变化。“touchscreen“
The touchscreen has changed. (This should never normally happen.)“keyboard“
The keyboard type has changed — for example, the user has plugged in an external keyboard.键盘模式发生变化，例如：用户接入外部键盘输入。“keyboardHidden“
The keyboard accessibility has changed — for example, the user has slid the keyboard out to expose it.用户打开手机硬件键盘“navigation“
The navigation type has changed. (This should never normally happen.)“orientation“
The screen orientation has changed — that is, the user has rotated the device.设备旋转，横向显示和竖向显示模式切换。“fontScale“
The font scaling factor has changed — that is, the user has selected a new global font size.全局字体大小缩放发生改变
项目的AndroidManifest.xml文件配置方法:
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | <manifest xmlns:android="" package="com.androidres.ConfigChangedTesting" android:versionCode="1" android:versionName="1.0.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".ConfigChangedTesting" android:label="@string/app_name" android:configChanges="keyboardHidden|orientation"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> |
二、横竖屏切换时候 Activity 的生命周期
测试代码：
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 | public class AndroidLifecycle extends Activity { private String TAG = "AndroidLifecycle"; public void onCreate(Bundle savedInstanceState) { Log.i(TAG,"AndroidLifecycle =======onCreate()========"); super.onCreate(savedInstanceState); setContentView(R.layout.main); }
@Override protected void onSaveInstanceState(Bundle outState) { Log.i(TAG,"AndroidLifecycle =======onSaveInstanceState()========"); super.onSaveInstanceState(outState); }
@Override protected void onRestoreInstanceState(Bundle outState) { Log.i(TAG,"AndroidLifecycle=======onRestoreInstanceState()========"); super.onRestoreInstanceState(outState); }
@Override public void onConfigurationChanged(Configuration newConfig) { Log.i(TAG,"AndroidLifecycle =======onConfigurationChanged()========"); super.onConfigurationChanged(newConfig); }
// Called after onCreate — or after onRestart when the activity had been // stopped, but is now again being displayed to the user. It will be // followed by onResume protected void onStart() { Log.i(TAG,"AndroidLifecycle =======onStart()========"); super.onStart(); }
// Called after onRestoreInstanceState, onRestart, or onPause, for your // activity to start interacting with the user protected void onResume() { Log.i(TAG,"AndroidLifecycle =======onResume()========"); super.onResume(); }
// Called as part of the activity lifecycle when an activity is going into // the background, but has not (yet) been killed protected void onPause() { Log.i(TAG,"AndroidLifecycle =======onPause()========"); super.onPause(); }
// Called when you are no longer visible to the user. You will next receive // either onRestart, onDestroy, or nothing, depending on later user // activity. protected void onStop() { Log.i(TAG,"AndroidLifecycle =======onStop()========"); super.onStop(); }
// Perform any final cleanup before an activity is destroyed protected void onDestroy() { Log.i(TAG,"AndroidLifecycle =======onDestroy()========"); super.onDestroy(); }
// Called after onStop when the current activity is being re-displayed to // the user (the user has navigated back to it). It will be followed by // onStart and then onResume protected void onRestart() { Log.i(TAG,"AndroidLifecycle =======onRestart()========"); super.onRestart(); } } |
Activity属性配置：
| 1 2 3 4 5 6 7 8 9 10 11 | <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".AndroidLifecycle" android:label="@string/app_name" android:configChanges="orientation|keyboardHidden"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity>
</application> |
在 Android 2.2 模拟器上测试结果为：
1、不设置Activity的android:configChanges时：
Simulator_切换到横屏
Simulator_切换到竖屏
模拟器这种情况切屏会重新调用各个生命周期，切横屏时会生命周期执行一次，切竖屏时生命周期会执行两次，且横竖屏onConfigurationChanged未被调用。但是在HTC DESIRE HD(G10) 这款手机上测试结果为：生命周期都只执行一次，且横竖屏onConfigurationChanged未被调用。
2、设置Activity的android:configChanges="orientation"时：
Simulator_orientation_切换到横屏
Simulator_orientation_切换到竖屏
模拟器这种情况切屏还是会重新调用各个生命周期，切横屏onConfigurationChanged未执行、竖屏时onConfigurationChanged执行1次。但是在HTC DESIRE HD(G10) 这款手机上测试结果为：生命周期未发生变化，且横竖屏onConfigurationChanged都只执行一次。
3、设置Activity的android:configChanges="orientation|keyboardHidden"时：
Simulator_orientation_keyboardHidden_切换到横屏
Simulator_orientation_keyboardHidden_切换到竖屏
模拟器这种情况切屏不会重新调用各个生命周期，切横屏时onConfigurationChanged会执行1次，切竖屏时onConfigurationChanged方法调用2次。 但是在HTC DESIRE HD(G10) 这款手机上测试结果为：横竖屏onConfigurationChanged都只执行一次。
结论：可以看出在G10这款真机上测试的结果比模拟器更加合理。
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