TorchControl.java
/*
* Copyright 2019 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 androidx.camera.camera2.impl;
import androidx.annotation.NonNull;
import androidx.camera.core.TorchState;
import androidx.camera.core.impl.utils.Threads;
import androidx.camera.core.impl.utils.futures.Futures;
import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import com.google.common.util.concurrent.ListenableFuture;
/**
* Implementation of torch control used within {@link Camera2CameraControl}.
*/
// TODO(b/143514107): implement TorchControl
final class TorchControl {
private final Camera2CameraControl mCamera2CameraControl;
private final MutableLiveData<Integer> mTorchState;
TorchControl(@NonNull Camera2CameraControl camera2CameraControl) {
mCamera2CameraControl = camera2CameraControl;
mTorchState = new MutableLiveData<>(TorchState.OFF);
}
// TODO(b/143514107): return a functional ListenableFuture
ListenableFuture<Void> enableTorch(boolean enabled) {
setLiveDataValue(mTorchState, enabled ? TorchState.ON : TorchState.OFF);
return Futures.immediateFuture(null);
}
@NonNull
LiveData<Integer> getTorchState() {
return mTorchState;
}
private <T> void setLiveDataValue(@NonNull MutableLiveData<T> liveData, T value) {
if (Threads.isMainThread()) {
liveData.setValue(value);
} else {
liveData.postValue(value);
}
}
}