如题，Android 原生 Settings 里有个 电池电量百分比 的选项，打开后电池电量百分比会显示在状态栏。
基于 Android 13 ，
代码在 ./packages/apps/Settings/src/com/android/settings/display/BatteryPercentagePreferenceController.java ，
/** Copyright (C) 2016 The Android Open Source Project** Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/
package com.android.settings.display;import static android.provider.Settings.System.SHOW_BATTERY_PERCENT;import android.app.settings.SettingsEnums;
import android.content.Context;
import android.provider.Settings;import androidx.preference.Preference;
import androidx.preference.PreferenceScreen;
import androidx.preference.SwitchPreference;import com.android.internal.R;
import com.android.settings.Utils;
import com.android.settings.core.BasePreferenceController;
import com.android.settings.core.PreferenceControllerMixin;
import com.android.settings.overlay.FeatureFactory;/*** A controller to manage the switch for showing battery percentage in the status bar.*/public class BatteryPercentagePreferenceController extends BasePreferenceController implementsPreferenceControllerMixin, Preference.OnPreferenceChangeListener {private Preference mPreference;public BatteryPercentagePreferenceController(Context context, String preferenceKey) {super(context, preferenceKey);}@Overridepublic void displayPreference(PreferenceScreen screen) {super.displayPreference(screen);mPreference = screen.findPreference(getPreferenceKey());if (!Utils.isBatteryPresent(mContext)) {// Disable battery percentageonPreferenceChange(mPreference, false /* newValue */);}}@Overridepublic int getAvailabilityStatus() {if (!Utils.isBatteryPresent(mContext)) {return CONDITIONALLY_UNAVAILABLE;}return mContext.getResources().getBoolean(R.bool.config_battery_percentage_setting_available) ? AVAILABLE: UNSUPPORTED_ON_DEVICE;}@Overridepublic void updateState(Preference preference) {int setting = Settings.System.getInt(mContext.getContentResolver(),SHOW_BATTERY_PERCENT, 0);((SwitchPreference) preference).setChecked(setting == 1);}@Overridepublic boolean onPreferenceChange(Preference preference, Object newValue) {boolean showPercentage = (Boolean) newValue;Settings.System.putInt(mContext.getContentResolver(), SHOW_BATTERY_PERCENT,showPercentage ? 1 : 0);FeatureFactory.getFactory(mContext).getMetricsFeatureProvider().action(mContext, SettingsEnums.OPEN_BATTERY_PERCENTAGE, showPercentage);return true;}
}调整的关键代码是，
Settings.System.putInt(mContext.getContentResolver(), SHOW_BATTERY_PERCENT,showPercentage ? 1 : 0);
SHOW_BATTERY_PERCENT 定义在 ./frameworks/base/core/java/android/provider/Settings.java ，
public static final String SHOW_BATTERY_PERCENT = "status_bar_show_battery_percent";
adb 调试方法，
显示，
settings put system status_bar_show_battery_percent 1
不显示
settings put system status_bar_show_battery_percent 0
