MultiResultReceiver.java

/*
 * #%L
 * Wheelmap - App
 * %%
 * Copyright (C) 2011 - 2012 Michal Harakal - Michael Kroez - Sozialhelden e.V.
 * %%
 * Wheelmap App based on the Wheelmap Service by Sozialhelden e.V.
 * 
 * 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.
 * #L%
 */
package org.wheelmap.android.utils;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.ResultReceiver;
import android.util.Log;

import java.util.HashSet;
import java.util.Set;

/**
 * Its important, that this {@link ResultReceiver} is intended to live at a {@link Service} and a
 * receiver is just registering there. So multiple activities {@link Activity} can get info about
 * the state of a single service.
 */
public class MultiResultReceiver extends ResultReceiver {

    private static final String TAG = "MultiResultReceiver";

    private Set<ResultReceiver> mReceivers;

    private int mResultCode;

    private Bundle mResultData;

    public MultiResultReceiver(Handler handler) {
        super(handler);
        mReceivers = new HashSet<ResultReceiver>();
    }

    public void clearReceiver() {
        mReceivers.clear();
    }

    public int getReceiverCount() {
        return mReceivers.size();
    }

    public boolean addReceiver(ResultReceiver receiver, boolean resendLast) {
        boolean isAdded = false;

        if (receiver == null) {
            return false;
        }
        if (!mReceivers.contains(receiver)) {
            mReceivers.add(receiver);
            isAdded = true;
        }

        if (resendLast) {
            receiver.send(mResultCode, mResultData);
        }

        return isAdded;
    }

    public void removeReceiver(ResultReceiver receiver) {
        mReceivers.remove(receiver);
    }

    @Override
    protected void onReceiveResult(int resultCode, Bundle resultData) {
        boolean sentOnce = false;

        mResultCode = resultCode;
        mResultData = resultData;

        for (ResultReceiver receiver : mReceivers) {
            receiver.send(resultCode, resultData);
            sentOnce = true;
        }

        if (!sentOnce) {
            Log.w(TAG, "Dropping result on floor for code " + resultCode + ": "
                    + resultData.toString());
        }
    }
}