src.com.android.server.devicestate.DeviceStateProvider Maven / Gradle / Ivy
/*
* Copyright (C) 2020 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.server.devicestate;
import static android.hardware.devicestate.DeviceStateManager.MAXIMUM_DEVICE_STATE;
import static android.hardware.devicestate.DeviceStateManager.MINIMUM_DEVICE_STATE;
import android.annotation.IntRange;
/**
* Responsible for providing the set of supported {@link DeviceState device states} as well as the
* current device state.
*
* @see DeviceStatePolicy
*/
public interface DeviceStateProvider {
/**
* Registers a listener for changes in provider state.
*
* It is required that {@link Listener#onSupportedDeviceStatesChanged(DeviceState[])} be
* called followed by {@link Listener#onStateChanged(int)} with the initial values on successful
* registration of the listener.
*/
void setListener(Listener listener);
/** Callback for changes in {@link DeviceStateProvider} state. */
interface Listener {
/**
* Called to notify the listener of a change in supported {@link DeviceState device states}.
* Required to be called once on successful registration of the listener and then once on
* every subsequent change in supported device states.
*
* The set of device states can change based on the current hardware state of the device.
* For example, if a device state depends on a particular peripheral device (display, etc)
* it would only be reported as supported when the device is plugged. Otherwise, it should
* not be included in the set of supported states.
*
* The identifier for every provided device state must be unique and greater than or equal
* to zero and there must always be at least one supported device state.
*
* @param newDeviceStates array of supported device states.
*
* @throws IllegalArgumentException if the list of device states is empty or if one of the
* provided states contains an invalid identifier.
*/
void onSupportedDeviceStatesChanged(DeviceState[] newDeviceStates);
/**
* Called to notify the listener of a change in current device state. Required to be called
* once on successful registration of the listener and then once on every subsequent change
* in device state. Value must have been included in the set of supported device states
* provided in the most recent call to
* {@link #onSupportedDeviceStatesChanged(DeviceState[])}.
*
* @param identifier the identifier of the new device state.
*
* @throws IllegalArgumentException if the state is less than {@link MINIMUM_DEVICE_STATE}
* or greater than {@link MAXIMUM_DEVICE_STATE}.
*/
void onStateChanged(
@IntRange(from = MINIMUM_DEVICE_STATE, to = MAXIMUM_DEVICE_STATE) int identifier);
}
}