Java tutorial
/* * Copyright (C) 2013 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 android.hardware; import android.annotation.RequiresFeature; import android.annotation.SystemService; import android.content.Context; import android.content.pm.PackageManager; import android.os.RemoteException; import android.os.ServiceManager; import android.os.ServiceManager.ServiceNotFoundException; import android.util.Log; /** * Class that operates consumer infrared on the device. */ @SystemService(Context.CONSUMER_IR_SERVICE) @RequiresFeature(PackageManager.FEATURE_CONSUMER_IR) public final class ConsumerIrManager { private static final String TAG = "ConsumerIr"; private final String mPackageName; private final IConsumerIrService mService; /** * @hide to prevent subclassing from outside of the framework */ public ConsumerIrManager(Context context) throws ServiceNotFoundException { mPackageName = context.getPackageName(); mService = IConsumerIrService.Stub .asInterface(ServiceManager.getServiceOrThrow(Context.CONSUMER_IR_SERVICE)); } /** * Check whether the device has an infrared emitter. * * @return true if the device has an infrared emitter, else false. */ public boolean hasIrEmitter() { if (mService == null) { Log.w(TAG, "no consumer ir service."); return false; } try { return mService.hasIrEmitter(); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } /** * Transmit an infrared pattern * <p> * This method is synchronous; when it returns the pattern has * been transmitted. Only patterns shorter than 2 seconds will * be transmitted. * </p> * * @param carrierFrequency The IR carrier frequency in Hertz. * @param pattern The alternating on/off pattern in microseconds to transmit. */ public void transmit(int carrierFrequency, int[] pattern) { if (mService == null) { Log.w(TAG, "failed to transmit; no consumer ir service."); return; } try { mService.transmit(mPackageName, carrierFrequency, pattern); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } /** * Represents a range of carrier frequencies (inclusive) on which the * infrared transmitter can transmit */ public final class CarrierFrequencyRange { private final int mMinFrequency; private final int mMaxFrequency; /** * Create a segment of a carrier frequency range. * * @param min The minimum transmittable frequency in this range segment. * @param max The maximum transmittable frequency in this range segment. */ public CarrierFrequencyRange(int min, int max) { mMinFrequency = min; mMaxFrequency = max; } /** * Get the minimum (inclusive) frequency in this range segment. */ public int getMinFrequency() { return mMinFrequency; } /** * Get the maximum (inclusive) frequency in this range segment. */ public int getMaxFrequency() { return mMaxFrequency; } }; /** * Query the infrared transmitter's supported carrier frequencies * * @return an array of * {@link android.hardware.ConsumerIrManager.CarrierFrequencyRange} * objects representing the ranges that the transmitter can support, or * null if there was an error communicating with the Consumer IR Service. */ public CarrierFrequencyRange[] getCarrierFrequencies() { if (mService == null) { Log.w(TAG, "no consumer ir service."); return null; } try { int[] freqs = mService.getCarrierFrequencies(); if (freqs.length % 2 != 0) { Log.w(TAG, "consumer ir service returned an uneven number of frequencies."); return null; } CarrierFrequencyRange[] range = new CarrierFrequencyRange[freqs.length / 2]; for (int i = 0; i < freqs.length; i += 2) { range[i / 2] = new CarrierFrequencyRange(freqs[i], freqs[i + 1]); } return range; } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } } }