修改默认值
在安卓源码中，要对安卓的一些默认属性配置进行修改的话（比如：修改背光默认，修改默认锁屏开关，休眠时间等等），我们可以非常容易地找到一个xml档·
其xml档在/frameworks/base/packages/SettingsProvider/res/values/defaults.xml
true
-1
-1
false
cell,bluetooth,wifi,nfc,wimax
bluetooth,wifi,nfc
true
true
true
255
false
100%
100%
true
false
false
false
true
gps
true
true
true
false
2
true
false
android/com.android.internal.backup.LocalTransport
true
true
false
true
true
1
/system/media/audio/ui/LowBattery.ogg
0
/system/media/audio/ui/Dock.ogg
/system/media/audio/ui/Undock.ogg
/system/media/audio/ui/Dock.ogg
/system/media/audio/ui/Undock.ogg
1
/system/media/audio/ui/Lock.ogg
/system/media/audio/ui/Unlock.ogg
/system/media/audio/ui/Trusted.ogg
/system/media/audio/ui/WirelessChargingStarted.ogg
true
false
1
true
true
false
false
0x13=0x01000100;
0x14=0x01010100;
0x15=0x02000001;
0x16=0x02010001;
0x200000013=0x02000601;
0x200000014=0x02010601;
0x200000015=0x03020101;
0x200000016=0x03010201;
0x200000023=0x02000301;
0x200000024=0x02010301;
0x200000037=0x03070201;
0x200000038=0x03000701:0x03010701:0x03020701;
https://ssl.gstatic.com/accessibility/javascript/android/AndroidVox_v1.js
false
200%
false
true
0
-1
-1
500
0
true
true
false
9
false
0
false
0
1
true
1
%1$s %2$s
%1$s
true
true
在此，找出几个做事例：
-
-1 -
true -
255
当我们部分编译完成之后，将生成的apk文件push到我们的手机上，发现竟然没有任何效果～～，这是什么原因导致的呢？
说一下博主的解决方案，原因在于获取xml的值后，是对数据库settings.db进行操作，因此即使我们push进去apk，但这个数据库没有发生变动，因此会没有修改，然后博主对用户空间和cashe进行恢复出厂设置就可以顺利了
adb reboot bootloader
fastboot -w
fastboot reboot
那么是谁在进行了数据库的操作呢？
setting.db跟踪
当我对相关的xml的值进行追踪的时候，发现了
/frameworks/base/packages/SettingsProvider/src/com/android/providers/settings/DatabaseHelper.java
这个java文件就是对数据库setting.db,进行的操作，那么我们以def_screen_brightness_automatic_mode为追踪对象.
/**
* Database helper class for {@link SettingsProvider}.
* Mostly just has a bit {@link #onCreate} to initialize the database.
*/
public class DatabaseHelper extends SQLiteOpenHelper {
private static final String TAG = "SettingsProvider";
private static final String DATABASE_NAME = "settings.db";
private static final int TYPE_NONE = -1;
// Please, please please. If you update the database version, check to make sure the
// database gets upgraded properly. At a minimum, please confirm that 'upgradeVersion'
// is properly propagated through your change. Not doing so will result in a loss of user
// settings.
private static final int DATABASE_VERSION = 113;
....
这里可以看到DatabaseHelper其实是继承了SQLiteOpenHelper这个类·其数据库的名字为settings.db·其版本是113
更新数据库
看到 public void onUpgrade(SQLiteDatabase db, int oldVersion, int currentVersion)这个函数，就是对数据库的更新
if (upgradeVersion < 108) {
// Reset the auto-brightness setting to default since the behavior
// of the feature is now quite different and is being presented to
// the user in a new way as "adaptive brightness".
db.beginTransaction();
SQLiteStatement stmt = null;
try {
stmt = db.compileStatement("INSERT OR REPLACE INTO system(name,value)"
+ " VALUES(?,?);");
loadBooleanSetting(stmt, Settings.System.SCREEN_BRIGHTNESS_MODE,
R.bool.def_screen_brightness_automatic_mode);
db.setTransactionSuccessful();
} finally {
db.endTransaction();
if (stmt != null) stmt.close();
}
upgradeVersion = 108;
}
再追loadBooleanSetting；
private void loadBooleanSetting(SQLiteStatement stmt, String key, int resid) {
loadSetting(stmt, key,
mContext.getResources().getBoolean(resid) ? "1" : "0");
}
再追loadSetting；
private void loadSetting(SQLiteStatement stmt, String key, Object value) {
stmt.bindString(1, key);
stmt.bindString(2, value.toString());
stmt.execute();
}
大致上我们可以看到是将相关的键值对存到数据库中，而且呢，这个键值对所谓的true或者false其实是0或者1·且是字符串类型的·
源码追到这里已经差不多了·
加载xml文件
private void loadSettings(SQLiteDatabase db) {
loadSystemSettings(db);
loadSecureSettings(db);
// The global table only exists for the 'owner' user
if (mUserHandle == UserHandle.USER_OWNER) {
loadGlobalSettings(db);
}
}
private void loadSystemSettings(SQLiteDatabase db) {
SQLiteStatement stmt = null;
try {
stmt = db.compileStatement("INSERT OR IGNORE INTO system(name,value)"
+ " VALUES(?,?);");
loadBooleanSetting(stmt, Settings.System.DIM_SCREEN,
R.bool.def_dim_screen);
loadIntegerSetting(stmt, Settings.System.SCREEN_OFF_TIMEOUT,
R.integer.def_screen_off_timeout);
// Set default cdma DTMF type
loadSetting(stmt, Settings.System.DTMF_TONE_TYPE_WHEN_DIALING, 0);
// Set default hearing aid
loadSetting(stmt, Settings.System.HEARING_AID, 0);
// Set default tty mode
loadSetting(stmt, Settings.System.TTY_MODE, 0);
loadIntegerSetting(stmt, Settings.System.SCREEN_BRIGHTNESS,
R.integer.def_screen_brightness);
loadBooleanSetting(stmt, Settings.System.SCREEN_BRIGHTNESS_MODE,
R.bool.def_screen_brightness_automatic_mode);
loadDefaultAnimationSettings(stmt);
loadBooleanSetting(stmt, Settings.System.ACCELEROMETER_ROTATION,
R.bool.def_accelerometer_rotation);
loadDefaultHapticSettings(stmt);
loadBooleanSetting(stmt, Settings.System.NOTIFICATION_LIGHT_PULSE,
R.bool.def_notification_pulse);
loadUISoundEffectsSettings(stmt);
loadIntegerSetting(stmt, Settings.System.POINTER_SPEED,
R.integer.def_pointer_speed);
loadStringSetting(stmt, Settings.System.TIME_12_24,
R.string.def_time_format);
loadStringSetting(stmt, Settings.System.DATE_FORMAT,
R.string.def_date_format);
} finally {
if (stmt != null) stmt.close();
}
}
在源码2400多行左右有loadSecureSettings函数，这个函数来加载xml文件中的各个选项
private void loadSecureSettings(SQLiteDatabase db) {
SQLiteStatement stmt = null;
try {
stmt = db.compileStatement("INSERT OR IGNORE INTO secure(name,value)"
+ " VALUES(?,?);");
loadStringSetting(stmt, Settings.Secure.LOCATION_PROVIDERS_ALLOWED,
R.string.def_location_providers_allowed);
String wifiWatchList = SystemProperties.get("ro.com.android.wifi-watchlist");
if (!TextUtils.isEmpty(wifiWatchList)) {
loadSetting(stmt, Settings.Secure.WIFI_WATCHDOG_WATCH_LIST, wifiWatchList);
}
// Don't do this. The SystemServer will initialize ADB_ENABLED from a
// persistent system property instead.
//loadSetting(stmt, Settings.Secure.ADB_ENABLED, 0);
// Allow mock locations default, based on build
loadSetting(stmt, Settings.Secure.ALLOW_MOCK_LOCATION,
"1".equals(SystemProperties.get("persist.env.c.allow.enable")) ? 1 : 0);
loadSecure35Settings(stmt);
loadBooleanSetting(stmt, Settings.Secure.MOUNT_PLAY_NOTIFICATION_SND,
R.bool.def_mount_play_notification_snd);
loadBooleanSetting(stmt, Settings.Secure.MOUNT_UMS_AUTOSTART,
R.bool.def_mount_ums_autostart);
loadBooleanSetting(stmt, Settings.Secure.MOUNT_UMS_PROMPT,
R.bool.def_mount_ums_prompt);
loadBooleanSetting(stmt, Settings.Secure.MOUNT_UMS_NOTIFY_ENABLED,
R.bool.def_mount_ums_notify_enabled);
loadBooleanSetting(stmt, Settings.Secure.ACCESSIBILITY_SCRIPT_INJECTION,
R.bool.def_accessibility_script_injection);
loadStringSetting(stmt, Settings.Secure.ACCESSIBILITY_WEB_CONTENT_KEY_BINDINGS,
R.string.def_accessibility_web_content_key_bindings);
loadIntegerSetting(stmt, Settings.Secure.LONG_PRESS_TIMEOUT,
R.integer.def_long_press_timeout_millis);
loadBooleanSetting(stmt, Settings.Secure.TOUCH_EXPLORATION_ENABLED,
R.bool.def_touch_exploration_enabled);
loadBooleanSetting(stmt, Settings.Secure.ACCESSIBILITY_SPEAK_PASSWORD,
R.bool.def_accessibility_speak_password);
loadStringSetting(stmt, Settings.Secure.ACCESSIBILITY_SCREEN_READER_URL,
R.string.def_accessibility_screen_reader_url);
if (SystemProperties.getBoolean("ro.lockscreen.disable.default", false) == true) {
loadSetting(stmt, Settings.System.LOCKSCREEN_DISABLED, "1");
} else {
loadBooleanSetting(stmt, Settings.System.LOCKSCREEN_DISABLED,
R.bool.def_lockscreen_disabled);
}
loadBooleanSetting(stmt, Settings.Secure.SCREENSAVER_ENABLED,
com.android.internal.R.bool.config_dreamsEnabledByDefault);
loadBooleanSetting(stmt, Settings.Secure.SCREENSAVER_ACTIVATE_ON_DOCK,
com.android.internal.R.bool.config_dreamsActivatedOnDockByDefault);
loadBooleanSetting(stmt, Settings.Secure.SCREENSAVER_ACTIVATE_ON_SLEEP,
com.android.internal.R.bool.config_dreamsActivatedOnSleepByDefault);
loadStringSetting(stmt, Settings.Secure.SCREENSAVER_COMPONENTS,
com.android.internal.R.string.config_dreamsDefaultComponent);
loadStringSetting(stmt, Settings.Secure.SCREENSAVER_DEFAULT_COMPONENT,
com.android.internal.R.string.config_dreamsDefaultComponent);
loadBooleanSetting(stmt, Settings.Secure.ACCESSIBILITY_DISPLAY_MAGNIFICATION_ENABLED,
R.bool.def_accessibility_display_magnification_enabled);
loadFractionSetting(stmt, Settings.Secure.ACCESSIBILITY_DISPLAY_MAGNIFICATION_SCALE,
R.fraction.def_accessibility_display_magnification_scale, 1);
loadBooleanSetting(stmt,
Settings.Secure.ACCESSIBILITY_DISPLAY_MAGNIFICATION_AUTO_UPDATE,
R.bool.def_accessibility_display_magnification_auto_update);
loadBooleanSetting(stmt, Settings.Secure.USER_SETUP_COMPLETE,
R.bool.def_user_setup_complete);
loadStringSetting(stmt, Settings.Secure.IMMERSIVE_MODE_CONFIRMATIONS,
R.string.def_immersive_mode_confirmations);
loadBooleanSetting(stmt, Settings.Secure.INSTALL_NON_MARKET_APPS,
R.bool.def_install_non_market_apps);
loadBooleanSetting(stmt, Settings.Secure.WAKE_GESTURE_ENABLED,
R.bool.def_wake_gesture_enabled);
loadIntegerSetting(stmt, Secure.LOCK_SCREEN_SHOW_NOTIFICATIONS,
R.integer.def_lock_screen_show_notifications);
loadBooleanSetting(stmt, Secure.LOCK_SCREEN_ALLOW_PRIVATE_NOTIFICATIONS,
R.bool.def_lock_screen_allow_private_notifications);
loadIntegerSetting(stmt, Settings.Secure.SLEEP_TIMEOUT,
R.integer.def_sleep_timeout);
if (!TextUtils.isEmpty(mContext.getResources().getString(R.string.def_input_method))) {
loadStringSetting(stmt, Settings.Secure.DEFAULT_INPUT_METHOD,
R.string.def_input_method);
}
if (!TextUtils.isEmpty(mContext.getResources().getString(
R.string.def_enable_input_methods))) {
loadStringSetting(stmt, Settings.Secure.ENABLED_INPUT_METHODS,
R.string.def_enable_input_methods);
}
// for accessibility enabled
loadStringSetting(stmt, Settings.Secure.ACCESSIBILITY_ENABLED,
R.integer.def_enable_accessiblity);
loadStringSetting(stmt, Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES,
R.string.def_enable_accessiblity_services);
} finally {
if (stmt != null) stmt.close();
}
上面的源码就是来加载xml·
static String dbNameForUser(final int userHandle) {
// The owner gets the unadorned db name;
if (userHandle == UserHandle.USER_OWNER) {
return DATABASE_NAME;
} else {
// Place the database in the user-specific data tree so that it's
// cleaned up automatically when the user is deleted.
File databaseFile = new File(
Environment.getUserSystemDirectory(userHandle), DATABASE_NAME);
return databaseFile.getPath();
}
}
public DatabaseHelper(Context context, int userHandle) {
super(context, dbNameForUser(userHandle), null, DATABASE_VERSION);
mContext = context;
mUserHandle = userHandle;
}
这2个函数一起看，可以知道在Setting中就可以使用getContentResolver()去查询对应的字段
该数据库名就是从dbNameForUser函数中得到·
关闭相关电源控制
在这个过程中一定要注意，要将设备的电源管理给关闭了
在frameworks/base/services/core/java/com/android/server/power/PowerManagerService.java
private int getScreenOffTimeoutLocked(int sleepTimeout) {
int timeout = mScreenOffTimeoutSetting;
//bsp add for never sleep device (debug require).
if (timeout < 0) {
timeout = mMaximumScreenOffTimeoutFromDeviceAdmin;
}
if (isMaximumScreenOffTimeoutFromDeviceAdminEnforcedLocked()) {
timeout = Math.min(timeout, mMaximumScreenOffTimeoutFromDeviceAdmin);
}
}