关于后台服务

时间:2018-10-06 17:59:43

标签: android mqtt iot

我正在为Android开发一个应用程序,该应用程序应该通过类似于MQTT的协议从Arduino设备接收一些通知。此通知将是一种警报,不会连续发生,但很少见。该服务将做一个精简的工作:接收单个通知,在sqlite数据库中注册,并将通知发送到系统栏。我应该为API级别26或更高级别使用哪种后台服务。我知道系统对运行后台服务施加了限制 谢谢 路易吉

1 个答案:

答案 0 :(得分:-1)

/*Note: IntentService is a service, and is therefore subject to the new restrictions on background services. As a result, many apps that rely on IntentService do not work properly when targeting Android 8.0 or higher. For this reason, Android Support Library 26.0.0 introduces a new JobIntentService class, which provides the same functionality as IntentService but uses jobs instead of services when running on Android 8.0 or higher.*/

import android.content.Context;
import android.content.Intent;
import android.os.Handler;
import android.os.SystemClock;
import android.support.v4.app.JobIntentService;
import android.util.Log;
import android.widget.Toast;

/**
 * Example implementation of a JobIntentService.
 */
public class SimpleJobIntentService extends JobIntentService {
    /**
     * Unique job ID for this service.
     */
    static final int JOB_ID = 1000;

    /**
     * Convenience method for enqueuing work in to this service.
     */
    static void enqueueWork(Context context, Intent work) {
        enqueueWork(context, SimpleJobIntentService.class, JOB_ID, work);
    }

    @Override
    protected void onHandleWork(Intent intent) {
        // We have received work to do.  The system or framework is already
        // holding a wake lock for us at this point, so we can just go.
        Log.i("SimpleJobIntentService", "Executing work: " + intent);
        String label = intent.getStringExtra("label");
        if (label == null) {
            label = intent.toString();
        }
        toast("Executing: " + label);
        for (int i = 0; i < 5; i++) {
            Log.i("SimpleJobIntentService", "Running service " + (i + 1)
                    + "/5 @ " + SystemClock.elapsedRealtime());
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
            }
        }
        Log.i("SimpleJobIntentService", "Completed service @ " + SystemClock.elapsedRealtime());
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        toast("All work complete");
    }

    final Handler mHandler = new Handler();

    // Helper for showing tests
    void toast(final CharSequence text) {
        mHandler.post(new Runnable() {
            @Override public void run() {
                Toast.makeText(SimpleJobIntentService.this, text, Toast.LENGTH_SHORT).show();
            }
        });
    }
}