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(Android数据传递)Service和Activity之间-- 借助BroadcastReceiver--的数据传递

实现逻辑如下:

左侧为Activity中的执行逻辑,右侧为Service中的执行逻辑:

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/**
 * <功能描述> Service和Activity之间的数据交互;具体表现为: 1. 从Service获取数据源,传递到Activity中; 2.
 * 在Activity中作数据更新; 3. Service中的onCreate()在UI线程中执行,作延时需要在子线程中执行;
 * 
 * @author Administrator
 */
public class MainActivity extends Activity {
    private static final String TAG = "Demo";
    private TextView mTvContent;
    private Intent mIntent;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        initView();
        registerReceiver();
        initData();
    }
    /**
     * <功能描述> 初始化视图
     * 
     * @return void [返回类型说明]
     */
    private void initView() {
        setContentView(R.layout.activity_main);
        mTvContent = (TextView) findViewById(R.id.tv_data);
    }
    /**
     * <功能描述> 初始化数据
     * 
     * @return void [返回类型说明]
     */
    private void initData() {
        mIntent = new Intent(MainActivity.this, CountService.class);
        startService(mIntent);
    }
    /**
     * <功能描述> 注册广播
     * 
     * @return void [返回类型说明]
     */
    private void registerReceiver() {
        IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction("com.spt.activity.CountService");
        MainActivity.this.registerReceiver(new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                Bundle bundle = intent.getExtras();
                mTvContent.setText(bundle
                        .getInt("com.spt.CountService.count_data") + "");
                Log.d(TAG, "count_data="http://www.mamicode.com/+ mTvContent.getText());>

需要在MainActivity中注册能够接收Service发送的数据更新广播:com.spt.activity.CountService;并获取到更新后的数据,显示即可。

还需要注意的是:开启服务后,还要停止服务。否则该服务会一直在后台运行。

还发现,使用这种方式同样能够停止该Service:

stopService(new Intent(MainActivity.this, CountService.class));

CountService服务代码如下:

public class CountService extends Service {
    private int countService = 0;
    private boolean isServiceRunning = false;
    @Override
    public void onCreate() {
        super.onCreate();
        isServiceRunning = true;
        // 创建子线程作计数
        new Thread(new Runnable() {
            @Override
            public void run() {
                while (isServiceRunning) {
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    countService++;
                    Intent intent = new Intent();
                    intent.putExtra("com.spt.CountService.count_data", countService);
                    intent.setAction("com.spt.activity.CountService");
                    // Service中发送广播
                    sendBroadcast(intent);
                }
            }
        }).start();
    }
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
    @Override
    public void onDestroy() {
        super.onDestroy();
        isServiceRunning = false;
        countService = 0;
    }
}

总结和疑问:

1. 使用Broadcast广播方式实现服务和宿主之间的数据交互,容易造成性能不高的问题;

2. 广播发送的时间不确定性因素,导致数据交互有延时;

(Android数据传递)Service和Activity之间-- 借助BroadcastReceiver--的数据传递