Android Settings 按住电源按钮

如题，Android 原生 Settings 里有个按住电源按钮的选项，可以设置按住电源按钮的操作。
在这里插入图片描述

按住电源按钮

两个选项的 UI 是分离的，

电源菜单

代码在 packages/apps/Settings/src/com/android/settings/gestures/LongPressPowerForPowerMenuPreferenceController.java ，

/*
 * Copyright (C) 2022 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.gestures;

import android.content.Context;
import android.net.Uri;

import androidx.lifecycle.Lifecycle;
import androidx.lifecycle.LifecycleObserver;
import androidx.lifecycle.OnLifecycleEvent;
import androidx.preference.Preference;
import androidx.preference.PreferenceScreen;

import com.android.settings.R;
import com.android.settings.core.BasePreferenceController;
import com.android.settingslib.widget.SelectorWithWidgetPreference;

/**
 * Configures the behaviour of the radio selector to configure long press power button to Power
 * Menu.
 */
public class LongPressPowerForPowerMenuPreferenceController extends BasePreferenceController
        implements PowerMenuSettingsUtils.SettingsStateCallback,
                SelectorWithWidgetPreference.OnClickListener,
                LifecycleObserver {

    private SelectorWithWidgetPreference mPreference;
    private final PowerMenuSettingsUtils mUtils;

    public LongPressPowerForPowerMenuPreferenceController(Context context, String key) {
        super(context, key);
        mUtils = new PowerMenuSettingsUtils(context);
    }

    @Override
    public int getAvailabilityStatus() {
        return PowerMenuSettingsUtils.isLongPressPowerSettingAvailable(mContext)
                ? AVAILABLE
                : UNSUPPORTED_ON_DEVICE;
    }

    @Override
    public void displayPreference(PreferenceScreen screen) {
        super.displayPreference(screen);
        mPreference = screen.findPreference(getPreferenceKey());
        if (mPreference != null) {
            mPreference.setOnClickListener(this);
        }
    }

    @Override
    public void updateState(Preference preference) {
        super.updateState(preference);
        if (preference instanceof SelectorWithWidgetPreference) {
            ((SelectorWithWidgetPreference) preference)
                    .setChecked(
                            !PowerMenuSettingsUtils.isLongPressPowerForAssistantEnabled(mContext));
        }
    }

    @Override
    public void onRadioButtonClicked(SelectorWithWidgetPreference preference) {
        PowerMenuSettingsUtils.setLongPressPowerForPowerMenu(mContext);
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

    @Override
    public void onChange(Uri uri) {
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

    /** @OnLifecycleEvent(Lifecycle.Event.ON_START) */
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void onStart() {
        mUtils.registerObserver(this);
    }

    /** @OnLifecycleEvent(Lifecycle.Event.ON_STOP) */
    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    public void onStop() {
        mUtils.unregisterObserver();
    }
}

关键代码，

    @Override
    public void onRadioButtonClicked(SelectorWithWidgetPreference preference) {
        PowerMenuSettingsUtils.setLongPressPowerForPowerMenu(mContext);
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

数字助理

代码在 packages/apps/Settings/src/com/android/settings/gestures/LongPressPowerForAssistantPreferenceController.java ，

/*
 * Copyright (C) 2022 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.gestures;

import android.content.Context;
import android.net.Uri;

import androidx.lifecycle.Lifecycle;
import androidx.lifecycle.LifecycleObserver;
import androidx.lifecycle.OnLifecycleEvent;
import androidx.preference.Preference;
import androidx.preference.PreferenceScreen;

import com.android.settings.R;
import com.android.settings.core.BasePreferenceController;
import com.android.settingslib.widget.SelectorWithWidgetPreference;

/**
 * Configures the behaviour of the radio selector to configure long press power button to Assistant.
 */
public class LongPressPowerForAssistantPreferenceController extends BasePreferenceController
        implements PowerMenuSettingsUtils.SettingsStateCallback,
                SelectorWithWidgetPreference.OnClickListener,
                LifecycleObserver {

    private SelectorWithWidgetPreference mPreference;
    private final PowerMenuSettingsUtils mUtils;

    public LongPressPowerForAssistantPreferenceController(Context context, String key) {
        super(context, key);
        mUtils = new PowerMenuSettingsUtils(context);
    }

    @Override
    public int getAvailabilityStatus() {
        return PowerMenuSettingsUtils.isLongPressPowerSettingAvailable(mContext)
                ? AVAILABLE
                : UNSUPPORTED_ON_DEVICE;
    }

    @Override
    public void displayPreference(PreferenceScreen screen) {
        super.displayPreference(screen);
        mPreference = screen.findPreference(getPreferenceKey());
        if (mPreference != null) {
            mPreference.setOnClickListener(this);
        }
    }

    @Override
    public void updateState(Preference preference) {
        super.updateState(preference);
        if (preference instanceof SelectorWithWidgetPreference) {
            ((SelectorWithWidgetPreference) preference)
                    .setChecked(
                            PowerMenuSettingsUtils.isLongPressPowerForAssistantEnabled(mContext));
        }
    }

    @Override
    public void onRadioButtonClicked(SelectorWithWidgetPreference preference) {
        PowerMenuSettingsUtils.setLongPressPowerForAssistant(mContext);
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

    @Override
    public void onChange(Uri uri) {
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

    /** @OnLifecycleEvent(Lifecycle.Event.ON_START) */
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void onStart() {
        mUtils.registerObserver(this);
    }

    /** @OnLifecycleEvent(Lifecycle.Event.ON_STOP) */
    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    public void onStop() {
        mUtils.unregisterObserver();
    }
}

关键代码，

    @Override
    public void onRadioButtonClicked(SelectorWithWidgetPreference preference) {
        PowerMenuSettingsUtils.setLongPressPowerForAssistant(mContext);
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

功能设置

实际设置是在 packages/apps/Settings/src/com/android/settings/gestures/PowerMenuSettingsUtils.java ，

    private static final String POWER_BUTTON_LONG_PRESS_SETTING =
            Settings.Global.POWER_BUTTON_LONG_PRESS;

    private static final int LONG_PRESS_POWER_GLOBAL_ACTIONS = 1; // a.k.a., Power Menu
    private static final int LONG_PRESS_POWER_ASSISTANT_VALUE = 5; // Settings.Secure.ASSISTANT

    // ... 
    public static boolean setLongPressPowerForAssistant(Context context) {
        if (Settings.Global.putInt(
                context.getContentResolver(),
                POWER_BUTTON_LONG_PRESS_SETTING,
                LONG_PRESS_POWER_ASSISTANT_VALUE)) {
            // Make power + volume up buttons to open the power menu
            Settings.Global.putInt(
                    context.getContentResolver(),
                    KEY_CHORD_POWER_VOLUME_UP_SETTING,
                    KEY_CHORD_POWER_VOLUME_UP_GLOBAL_ACTIONS);
            return true;
        }
        return false;
    }

    public static boolean setLongPressPowerForPowerMenu(Context context) {
        if (Settings.Global.putInt(
                context.getContentResolver(),
                POWER_BUTTON_LONG_PRESS_SETTING,
                LONG_PRESS_POWER_GLOBAL_ACTIONS)) {
            // We restore power + volume up buttons to the default action.
            int keyChordDefaultValue =
                    context.getResources()
                            .getInteger(KEY_CHORD_POWER_VOLUME_UP_DEFAULT_VALUE_RESOURCE);
            Settings.Global.putInt(
                    context.getContentResolver(),
                    KEY_CHORD_POWER_VOLUME_UP_SETTING,
                    keyChordDefaultValue);
            return true;
        }
        return false;
    }

追踪初始化逻辑

android.provider.Settings 相关调用的初始化一般都在 SettingsProvider 里，

找到 frameworks/base/packages/SettingsProvider/src/com/android/providers/settings/SettingsHelper.java ，

    /**
     * Correctly sets long press power button Behavior.
     *
     * The issue is that setting for LongPressPower button Behavior is not available on all devices
     * and actually changes default Behavior of two properties - the long press power button
     * and volume up + power button combo. OEM can also reconfigure these Behaviors in config.xml,
     * so we need to be careful that we don't irreversibly change power button Behavior when
     * restoring. Or switch to a non-default button Behavior.
     */
    private void setLongPressPowerBehavior(ContentResolver cr, String value) {
        // We will not restore the value if the long press power setting option is unavailable.
        if (!mContext.getResources().getBoolean(
                com.android.internal.R.bool.config_longPressOnPowerForAssistantSettingAvailable)) {
            return;
        }

        int longPressOnPowerBehavior;
        try {
            longPressOnPowerBehavior = Integer.parseInt(value);
        } catch (NumberFormatException e) {
            return;
        }

        if (longPressOnPowerBehavior < LONG_PRESS_POWER_NOTHING
                || longPressOnPowerBehavior > LONG_PRESS_POWER_FOR_ASSISTANT) {
            return;
        }

        // When user enables long press power for Assistant, we also switch the meaning
        // of Volume Up + Power key chord to the "Show power menu" option.
        // If the user disables long press power for Assistant, we switch back to default OEM
        // Behavior configured in config.xml. If the default Behavior IS "LPP for Assistant",
        // then we fall back to "Long press for Power Menu" Behavior.
        if (longPressOnPowerBehavior == LONG_PRESS_POWER_FOR_ASSISTANT) {
            Settings.Global.putInt(cr, Settings.Global.POWER_BUTTON_LONG_PRESS,
                    LONG_PRESS_POWER_FOR_ASSISTANT);
            Settings.Global.putInt(cr, Settings.Global.KEY_CHORD_POWER_VOLUME_UP,
                    KEY_CHORD_POWER_VOLUME_UP_GLOBAL_ACTIONS);
        } else {
            // We're restoring "LPP for Assistant Disabled" state, prefer OEM config.xml Behavior
            // if possible.
            int longPressOnPowerDeviceBehavior = mContext.getResources().getInteger(
                    com.android.internal.R.integer.config_longPressOnPowerBehavior);
            if (longPressOnPowerDeviceBehavior == LONG_PRESS_POWER_FOR_ASSISTANT) {
                // The default on device IS "LPP for Assistant Enabled" so fall back to power menu.
                Settings.Global.putInt(cr, Settings.Global.POWER_BUTTON_LONG_PRESS,
                        LONG_PRESS_POWER_GLOBAL_ACTIONS);
            } else {
                // The default is non-Assistant Behavior, so restore that default.
                Settings.Global.putInt(cr, Settings.Global.POWER_BUTTON_LONG_PRESS,
                        longPressOnPowerDeviceBehavior);
            }

            // Clear and restore default power + volume up Behavior as well.
            int powerVolumeUpDefaultBehavior = mContext.getResources().getInteger(
                    com.android.internal.R.integer.config_keyChordPowerVolumeUp);
            Settings.Global.putInt(cr, Settings.Global.KEY_CHORD_POWER_VOLUME_UP,
                    powerVolumeUpDefaultBehavior);
        }
    }

找到 config_longPressOnPowerBehavior ，定义在 frameworks/base/core/res/res/values/config.xml ，

    <!-- Control the behavior when the user long presses the power button.
            0 - Nothing
            1 - Global actions menu
            2 - Power off (with confirmation)
            3 - Power off (without confirmation)
            4 - Go to voice assist
            5 - Go to assistant (Settings.Secure.ASSISTANT)
    -->
    <integer name="config_longPressOnPowerBehavior">5</integer>

按住电源按钮的持续时间

代码在 packages/apps/Settings/src/com/android/settings/gestures/LongPressPowerSensitivityPreferenceController.java ，

/*
 * Copyright (C) 2021 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.gestures;

import android.content.Context;
import android.net.Uri;
import android.provider.Settings;

import androidx.annotation.Nullable;
import androidx.lifecycle.Lifecycle;
import androidx.lifecycle.LifecycleObserver;
import androidx.lifecycle.OnLifecycleEvent;
import androidx.preference.Preference;
import androidx.preference.PreferenceScreen;

import com.android.settings.core.SliderPreferenceController;
import com.android.settings.widget.LabeledSeekBarPreference;

/** Handles changes to the long press power button sensitivity slider. */
public class LongPressPowerSensitivityPreferenceController extends SliderPreferenceController
        implements PowerMenuSettingsUtils.SettingsStateCallback, LifecycleObserver {

    @Nullable
    private final int[] mSensitivityValues;

    private final PowerMenuSettingsUtils mUtils;

    @Nullable
    private LabeledSeekBarPreference mPreference;

    public LongPressPowerSensitivityPreferenceController(Context context, String preferenceKey) {
        super(context, preferenceKey);
        mSensitivityValues = context.getResources().getIntArray(
                com.android.internal.R.array.config_longPressOnPowerDurationSettings);
        mUtils = new PowerMenuSettingsUtils(context);
    }

    /** @OnLifecycleEvent(Lifecycle.Event.ON_START) */
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void onStart() {
        mUtils.registerObserver(this);
    }

    /** @OnLifecycleEvent(Lifecycle.Event.ON_STOP) */
    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    public void onStop() {
        mUtils.unregisterObserver();
    }

    @Override
    public void displayPreference(PreferenceScreen screen) {
        super.displayPreference(screen);
        mPreference = screen.findPreference(getPreferenceKey());
        if (mPreference != null) {
            mPreference.setContinuousUpdates(false);
            mPreference.setHapticFeedbackMode(
                    LabeledSeekBarPreference.HAPTIC_FEEDBACK_MODE_ON_TICKS);
            mPreference.setMin(getMin());
            mPreference.setMax(getMax());
        }
    }

    @Override
    public void updateState(Preference preference) {
        super.updateState(preference);
        final LabeledSeekBarPreference pref = (LabeledSeekBarPreference) preference;
        pref.setVisible(
                PowerMenuSettingsUtils.isLongPressPowerForAssistantEnabled(mContext)
                        && getAvailabilityStatus() == AVAILABLE);
        pref.setProgress(getSliderPosition());
    }

    @Override
    public int getAvailabilityStatus() {
        if (mSensitivityValues == null
                || mSensitivityValues.length < 2
                || !PowerMenuSettingsUtils.isLongPressPowerSettingAvailable(mContext)) {
            return UNSUPPORTED_ON_DEVICE;
        }
        return AVAILABLE;
    }

    @Override
    public int getSliderPosition() {
        return mSensitivityValues == null ? 0 : closestValueIndex(mSensitivityValues,
                getCurrentSensitivityValue());
    }

    @Override
    public boolean setSliderPosition(int position) {
        if (mSensitivityValues == null || position < 0 || position >= mSensitivityValues.length) {
            return false;
        }
        return Settings.Global.putInt(mContext.getContentResolver(),
                Settings.Global.POWER_BUTTON_LONG_PRESS_DURATION_MS,
                mSensitivityValues[position]);
    }

    @Override
    public void onChange(Uri uri) {
        if (mPreference != null) {
            updateState(mPreference);
        }
    }

    @Override
    public int getMax() {
        if (mSensitivityValues == null || mSensitivityValues.length == 0) {
            return 0;
        }
        return mSensitivityValues.length - 1;
    }

    @Override
    public int getMin() {
        return 0;
    }

    private int getCurrentSensitivityValue() {
        return Settings.Global.getInt(mContext.getContentResolver(),
                Settings.Global.POWER_BUTTON_LONG_PRESS_DURATION_MS,
                mContext.getResources().getInteger(
                        com.android.internal.R.integer.config_longPressOnPowerDurationMs));
    }

    private static int closestValueIndex(int[] values, int needle) {
        int minDistance = Integer.MAX_VALUE;
        int valueIndex = 0;
        for (int i = 0; i < values.length; i++) {
            int diff = Math.abs(values[i] - needle);
            if (diff < minDistance) {
                minDistance = diff;
                valueIndex = i;
            }
        }
        return valueIndex;
    }
}

R.array.config_longPressOnPowerDurationSettings 定义在 frameworks/base/core/res/res/values/config.xml ，

    <!-- The possible UI options to be surfaced for configuring long press power on duration
         action. Value set in config_longPressOnPowerDurationMs should be one of the available
         options to allow users to restore default. -->
    <integer-array name="config_longPressOnPowerDurationSettings">
        <item>250</item>
        <item>350</item>
        <item>500</item>
        <item>650</item>
        <item>750</item>
    </integer-array>