remoteservicebinding.java

android 模拟器

/* 
 * Copyright (C) 2007 Google Inc.
 *
 * 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.google.android.samples.app;

import com.google.android.samples.R;

import android.app.Activity;
import android.app.NotificationManager;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.DeadObjectException;
import android.os.IBinder;
import android.os.Process;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;


/**
 * <p>Example of binding and unbinding to the {@link RemoteService}.
 * This demonstrates the implementation of a service which the client will
bind to, receiving an object through which it can communicate with the service.</p>

<h4>Demo</h4>
App/Service/Remote Service Binding
 
<h4>Source files</h4>
<table class="LinkTable">
        <tr>
            <td class="LinkColumn">src/com/google/android/samples/app/RemoteServiceBinding.java</td>
            <td class="DescrColumn">The Remote Service Binding implementation</td>
        </tr>
        <tr>
            <td class="LinkColumn">src/com/google/android/samples/app/RemoteService.java</td>
            <td class="DescrColumn">The implementation of the service itself</td>
        </tr>
        <tr>
            <td class="LinkColumn">/res/any/layout/local_service_binding.xml</td>
            <td class="DescrColumn">Defines contents of the screen</td>
        </tr>
</table>

 */

public class RemoteServiceBinding extends Activity
{
    IRemoteService mService = null;
    Button mKillButton;

    private boolean mIsBound;

    @Override
    protected void onCreate(Bundle icicle)
    {
        super.onCreate(icicle);

        setContentView(R.layout.remote_service_binding);

        // Watch for button clicks.
        Button button = (Button)findViewById(R.id.bind);
        button.setOnClickListener(mBindListener);
        button = (Button)findViewById(R.id.unbind);
        button.setOnClickListener(mUnbindListener);
        mKillButton = (Button)findViewById(R.id.kill);
        mKillButton.setOnClickListener(mKillListener);
        mKillButton.setEnabled(false);
    }

    private ServiceConnection mConnection = new ServiceConnection()
    {
        public void onServiceConnected(ComponentName className, IBinder service)
        {
            // This is called when the connection with the service has been
            // established, giving us the service object we can use to
            // interact with the service.  We are communicating with our
            // service through an IDL interface, so get a client-side
            // representation of that from the raw service object.
            mService = IRemoteService.Stub.asInterface((IBinder)service);
            mKillButton.setEnabled(true);

            // As part of the sample, tell the user what happened.
            NotificationManager nm = (NotificationManager)
                getSystemService(NOTIFICATION_SERVICE);
            nm.notifyWithText(R.string.remote_service_connected,
                      getText(R.string.remote_service_connected),
                      NotificationManager.LENGTH_SHORT,
                      null);
        }

        public void onServiceDisconnected(ComponentName className)
        {
            // This is called when the connection with the service has been
            // unexpectedly disconnected -- that is, its process crashed.
            mService = null;
            mKillButton.setEnabled(false);

            // As part of the sample, tell the user what happened.
            NotificationManager nm = (NotificationManager)
                    getSystemService(NOTIFICATION_SERVICE);
            nm.notifyWithText(R.string.remote_service_disconnected,
                      getText(R.string.remote_service_disconnected),
                      NotificationManager.LENGTH_SHORT,
                      null);
        }
    };

    private OnClickListener mBindListener = new OnClickListener()
    {
        public void onClick(View v)
        {
            // Establish a connection with the service, by its class name.
            bindService(new Intent(RemoteServiceBinding.this,
                        RemoteService.class),
                    null, mConnection, Context.BIND_AUTO_CREATE);
            mIsBound = true;
        }
    };

    private OnClickListener mUnbindListener = new OnClickListener()
    {
        public void onClick(View v)
        {
            if (mIsBound) {
                // Detach our existing connection.
                unbindService(mConnection);
                mKillButton.setEnabled(false);
                mIsBound = false;
            }
        }
    };

    private OnClickListener mKillListener = new OnClickListener()
    {
        public void onClick(View v)
        {
            // To kill the process hosting our service, we need to know its
            // PID.  Conveniently our service has a call that will return
            // to us that information.
            if (mService != null) {
                int pid = -1;
                try {
                    pid = mService.getPid();
                } catch (DeadObjectException ex) {
                    // Recover gracefully from the process hosting the
                    // server dying.
                    // Just for purposes of the sample, put up a notification.
                    NotificationManager nm = (NotificationManager)
                        getSystemService(NOTIFICATION_SERVICE);
                    nm.notifyWithText(R.string.remote_call_failed,
                              getText(R.string.remote_call_failed),
                              NotificationManager.LENGTH_SHORT,
                              null);
                }

                if (pid > 0) {
                    // Go away!
                    Process.killProcess(pid);
                }
            }
        }
    };
}