Android V Settings应用启动APN Settings界面的代码逻辑

本文主要是介绍Android V Settings应用启动APN Settings界面的代码逻辑，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

逻辑说明

1、manifest清单文件配置<activity>（如ApnSettingsActivity），通过配置内部元元素<meta-data>元数据绑定界面对应的java类（如下案例绑定Fragement是ApnSettings类）

静态内部类在AndroidManifest.xml文件中通过<meta-data>将相应的Fragment绑定起来。

<activity android:name="Settings$ApnSettingsActivity"    <meta-data android:name="com.android.settings.FRAGMENT_CLASS"android:value="com.android.settings.network.apn.ApnSettings" />

2、ApnSettings（Fragment）是界面的具体逻辑实现

说明：

Settings类中定义各子静态xxxSettingsActivity类
Settings类和各子xxxSettingsActivity都继承自SettingsActivity类
Settings与SubSettings中基本是空Activity，即Activity没有重写任意7大生命周期方法（/*empty*/）

代码案例

Settings应用

AndroidManifest.xml

<meta-data>元素可用于在AndroidManifest.xml文件中为应用程序、组件或权限声明添加一些附加信息。

<intent-filter>元素用来描述组件（如活动、服务或接收器）能够响应的Intent的一部分。它通常用于在清单文件中声明组件所需的Intent过滤器。

1、其中包含了<action>和<category>元素。<action>元素指定了组件能够处理的Intent动作，而<category>元素用于进一步限制组件的响应条件。

2、也可以在其中包含android:priority属性，用来指定组件处理对应Intent的优先级，数字越大优先级越高。

在Java中，用$符号来表示嵌套类和内部类的关系。所以这个声明指明了ApnSettingsActivity是Settings类中的一个内部类。

<manifest xmlns:android="http://schemas.android.com/apk/res/android"xmlns:tools="http://schemas.android.com/tools"coreApp="true"android:sharedUserId="android.uid.system"> <!--表明应用运行在system进程--><original-package android:name="com.android.settings"/><!--应用配置--><applicationandroid:name=".SettingsApplication"android:label="@string/settings_label"android:icon="@drawable/ic_launcher_settings"android:theme="@style/Theme.Settings"android:hardwareAccelerated="true"android:requiredForAllUsers="true"android:supportsRtl="true"android:backupAgent="com.android.settings.backup.SettingsBackupHelper"android:restoreAnyVersion="true"android:usesCleartextTraffic="true"android:defaultToDeviceProtectedStorage="true"android:directBootAware="true"android:appComponentFactory="androidx.core.app.CoreComponentFactory"android:gwpAsanMode="always"android:enableOnBackInvokedCallback="true"tools:replace="android:label"><!--Activity属性--><!--指明ApnSettingsActivity是Settings类中的一个内部类。--><activity android:name="Settings$ApnSettingsActivity"android:label="@string/apn_settings"android:exported="true"android:configChanges="orientation|keyboardHidden|screenSize"><intent-filter android:priority="1"><action android:name="android.settings.APN_SETTINGS" /><category android:name="android.intent.category.DEFAULT" /></intent-filter><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.DEFAULT" /><category android:name="android.intent.category.VOICE_LAUNCH" /></intent-filter><!--绑定界面ApnSettings--><meta-data android:name="com.android.settings.PRIMARY_PROFILE_CONTROLLED"android:value="true" /><meta-data android:name="com.android.settings.FRAGMENT_CLASS"android:value="com.android.settings.network.apn.ApnSettings" /><meta-data android:name="com.android.settings.HIGHLIGHT_MENU_KEY"android:value="@string/menu_key_network"/></activity></application>
</manifest>

Settings.java

结合清单文件配置的Settings$ApnSettingsActivity，说明ApnSettingsActivity是Settings类中的一个内部类，但没有具体的Activity实现，界面实现看meta-data绑定的Fragment。

package com.android.settings;/*** Top-level Settings activity*/
public class Settings extends SettingsActivity {/** Settings subclasses for launching independently.*/public static class ApnSettingsActivity extends SettingsActivity { /* empty */ }}

移动网络

mobile_network_settings.xml 布局文件

Settings\app\src\main\res\xml\mobile_network_settings.xml

用户界面路径：Settings -> Network&Internet -> SIMs -> xxx（运营商名称）。
APN菜单对应“telephony_apn_key”。

<PreferenceScreenxmlns:android="http://schemas.android.com/apk/res/android"xmlns:settings="http://schemas.android.com/apk/res-auto"android:key="mobile_network_pref_screen"><PreferenceCategoryandroid:key="enabled_state_container"android:title="@string/summary_placeholder"settings:controller="com.android.settings.network.telephony.DisabledSubscriptionController"android:layout="@layout/preference_category_no_label"><!--网络模式--><ListPreferenceandroid:key="preferred_network_mode_key"android:title="@string/preferred_network_mode_title"android:summary="@string/preferred_network_mode_summary"android:entries="@array/preferred_network_mode_choices"android:entryValues="@array/preferred_network_mode_values"android:dialogTitle="@string/preferred_network_mode_dialogtitle"settings:controller="com.android.settings.network.telephony.PreferredNetworkModePreferenceController"/><!--选网（自动/手动）--><PreferenceCategoryandroid:key="network_operators_category_key"android:title="@string/network_operator_category"settings:allowDividerBelow="true"settings:controller="com.android.settings.network.telephony.NetworkPreferenceCategoryController"><com.android.settings.spa.preference.ComposePreferenceandroid:key="auto_select_key"android:title="@string/select_automatically"settings:controller="com.android.settings.network.telephony.gsm.AutoSelectPreferenceController"/><Preferenceandroid:key="choose_network_key"android:title="@string/choose_network_title"settings:controller="com.android.settings.network.telephony.gsm.OpenNetworkSelectPagePreferenceController"/></PreferenceCategory><!--APN入口--><!--We want separate APN setting from reset of settings because we want user to change it with caution--><com.android.settingslib.RestrictedPreferenceandroid:key="telephony_apn_key"android:persistent="false"android:title="@string/mobile_network_apn_title"settings:keywords="@string/keywords_access_point_names"settings:controller="com.android.settings.network.telephony.ApnPreferenceController"/></PreferenceCategory></PreferenceScreen>

该界面可以disable/enable 卡，对应首行“Use this SIM”开关。

  <string name="mobile_network_use_sim_on">Use this SIM</string>

MobileNetworkSettings.java

Settings\app\src\java\com\android\settings\network\telephony\MobileNetworkSettings.java

package com.android.settings.network.telephony;@SearchIndexable(forTarget = SearchIndexable.ALL & ~SearchIndexable.ARC)
public class MobileNetworkSettings extends AbstractMobileNetworkSettings implementsMobileNetworkRepository.MobileNetworkCallback {public MobileNetworkSettings() {super(UserManager.DISALLOW_CONFIG_MOBILE_NETWORKS);}//Fragement生命周期之一，用于将Fragment与Activity进行关联。@Overridepublic void onAttach(Context context) {super.onAttach(context);//初始化注册信息if (mSubId == SubscriptionManager.INVALID_SUBSCRIPTION_ID) {Log.d(LOG_TAG, "Invalid subId, get the default subscription to show.");SubscriptionInfo info = SubscriptionUtil.getSubscriptionOrDefault(context, mSubId);if (info == null) {Log.d(LOG_TAG, "Invalid subId request " + mSubId);return;}mSubId = info.getSubscriptionId();Log.d(LOG_TAG, "Show NetworkSettings fragment for subId" + mSubId);}Intent intent = getIntent();if (intent != null) {int updateSubscriptionIndex = intent.getIntExtra(Settings.EXTRA_SUB_ID,SubscriptionManager.INVALID_SUBSCRIPTION_ID);//..omit}//传入intent值，对应的卡use(ApnPreferenceController.class).init(mSubId);}

onAttach()方法是Fragment的生命周期方法之一，用于将Fragment与Activity进行关联。

APN设置

ApnPreferenceController.java

Settings\app\src\main\java\com\android\settings\network\telephony\ApnPreferenceController.java

插件化：可以在此处初始化的时候安装插件
【疑问】为什么APN Settings 注释是跑在phone进程的？？

package com.android.settings.network.telephony;/*** Preference controller for "Apn settings"*/
public class ApnPreferenceController extends TelephonyBasePreferenceController implementsLifecycleObserver, OnStart, OnStop {@VisibleForTestingCarrierConfigCache mCarrierConfigCache;private Preference mPreference;private DpcApnEnforcedObserver mDpcApnEnforcedObserver;public ApnPreferenceController(Context context, String key) {super(context, key);mCarrierConfigCache = CarrierConfigCache.getInstance(context);mDpcApnEnforcedObserver = new DpcApnEnforcedObserver(new Handler(Looper.getMainLooper()));}@Overridepublic int getAvailabilityStatus(int subId) {final PersistableBundle carrierConfig = mCarrierConfigCache.getConfigForSubId(subId);final boolean isCdmaApn = MobileNetworkUtils.isCdmaOptions(mContext, subId)&& carrierConfig != null&& carrierConfig.getBoolean(CarrierConfigManager.KEY_SHOW_APN_SETTING_CDMA_BOOL);final boolean isGsmApn = MobileNetworkUtils.isGsmOptions(mContext, subId)&& carrierConfig != null&& carrierConfig.getBoolean(CarrierConfigManager.KEY_APN_EXPAND_BOOL);final boolean hideCarrierNetwork = carrierConfig == null|| carrierConfig.getBoolean(CarrierConfigManager.KEY_HIDE_CARRIER_NETWORK_SETTINGS_BOOL);return !hideCarrierNetwork && (isCdmaApn || isGsmApn)? AVAILABLE: CONDITIONALLY_UNAVAILABLE;}@Overridepublic void onStart() {mDpcApnEnforcedObserver.register(mContext);}@Overridepublic void onStop() {mDpcApnEnforcedObserver.unRegister(mContext);}//根据APN key显示 preference@Overridepublic void displayPreference(PreferenceScreen screen) {super.displayPreference(screen);mPreference = screen.findPreference(getPreferenceKey());}@Overridepublic void updateState(Preference preference) {super.updateState(preference);if (mPreference == null) {return;}((RestrictedPreference) mPreference).setDisabledByAdmin(MobileNetworkUtils.isDpcApnEnforced(mContext)? RestrictedLockUtilsInternal.getDeviceOwner(mContext): null);}//点击跳转到APN Settings@Overridepublic boolean handlePreferenceTreeClick(Preference preference) {if (getPreferenceKey().equals(preference.getKey())) {// This activity runs in phone process, we must use intent to startfinal Intent intent = new Intent(Settings.ACTION_APN_SETTINGS);//为什么指示运行在Phone进程？//intent.setPackage(mContext.getPackageName());  //源码没有这句// This will setup the Home and Search affordanceintent.putExtra(SettingsActivity.EXTRA_SHOW_FRAGMENT_AS_SUBSETTING, true);intent.putExtra(ApnSettings.SUB_ID, mSubId);mContext.startActivity(intent);return true;}return false;}//从MobileNetworkSettings传入的值public void init(int subId) {mSubId = subId;}}

DPC 是 Android Device Policy Controller ？

ApnSettings.java 界面逻辑

package com.android.settings.network.apn;public class ApnSettings extends RestrictedSettingsFragmentimplements Preference.OnPreferenceChangeListener {public ApnSettings() {super(UserManager.DISALLOW_CONFIG_MOBILE_NETWORKS);}@Overridepublic void onCreate(Bundle icicle) {super.onCreate(icicle);//初始化全局变量，subId、phoneId、TelephonyManager相关及业务监听和Handler处理}@Overridepublic void onActivityCreated(Bundle savedInstanceState) {super.onActivityCreated(savedInstanceState);getEmptyTextView().setText(R.string.apn_settings_not_available);if (mUnavailable) {addPreferencesFromResource(R.xml.placeholder_prefs);return;}addPreferencesFromResource(R.xml.apn_settings);}@Overridepublic void onResume() {super.onResume();}@Overridepublic void onPause() {super.onPause();}@Overridepublic void onDestroy() {super.onDestroy();//取消各种监听，unregisterXxxxx//子线程关闭，mApnThread.quit();}@Overridepublic boolean onPreferenceChange(Preference preference, Object newValue) {//行点击触发，ApnEditor编译页面}//可以自定义覆写菜单显示逻辑，执行于onCreateOptionsMenu之前//解决加载菜单项异常问题，常见于定制导致的时序问题。@Overridepublic void onPrepareOptionsMenu(Menu menu) {//available判断逻辑和菜单功能定制super.onPrepareOptionsMenu(menu);}@Overridepublic void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {//客制化逻辑super.onCreateOptionsMenu(menu, inflater);}//菜单点击事件处理@Overridepublic boolean onOptionsItemSelected(MenuItem item) {switch (item.getItemId()) {case MENU_NEW:    //新增APNaddNewApn();return true;case MENU_RESTORE:    //重置APNrestoreDefaultApn();return true;}return super.onOptionsItemSelected(item);}

在Android中，onCreate()方法是在Activity创建时首先被调用的。这个方法用于进行一些初始化操作，比如设置布局、绑定控件以及准备数据等。

而onActivityCreated()方法则是Fragment中的生命周期方法，在Activity的onCreate()方法执行完毕之后，Fragment相关的生命周期方法才会被调用。所以onActivityCreated()方法会在Activity的onCreate()方法执行完毕之后才会被调用。

总结起来，onCreate()方法先于onActivityCreated()方法被执行。