对于那些想知道我是怎么做的人 . 我使用了Job Scheduler，因为它是一个需要 Build wifi连接的任务 .
此外，您可以查看my blog，在那里您可以找到有关此信息和额外信息的更多详细信息
最后，我得到了
首先，声明每个活动的文本视图 .
android:id="@+id/messageLogin"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/wifitoSlow"
android:textColor="@color/magnitude0"
android:background="@color/magnitude7"
android:gravity="center"
android:visibility="gone"
/>
然后我创建了一个具有JobCheduler的Class WfiJob，它需要NETWORK_TYPE_ANY，并且它每5秒执行一次 .
public class WifiJob {
public void createWifiJob(int jobNumber, Context context){
//We are defining a jobObject that will have a jobNumber and a serviceName that will run only if a network connection exits
JobScheduler jobScheduler = (JobScheduler)context.getSystemService(Context.JOB_SCHEDULER_SERVICE);
jobScheduler.schedule(new JobInfo.Builder(jobNumber, new ComponentName(context.getApplicationContext(), WifiJobScheduler.class))
.setRequiredNetworkType(WORK_TYPE_ANY)
.setRequiresDeviceIdle(false)
.setPeriodic(5000).build());
}
}
然后是我从JobService扩展的WifiJobScheduler . 在这里我还有WifiStrenghtListener，它是一个接口，它将向活动广播一条消息，以便显示textview .
public class WifiJobScheduler extends JobService{
private static final String TAG = "SyncService";
public static WifiStrenghtListener wifiStrenghtListener=null;
//private boolean messageIsShowed = false;
//The onStartJob is performed in the main thread, if you start asynchronous processing in this method, return true otherwise false.
@Override
public boolean onStartJob(JobParameters params) {
Log.i(TAG, "on start job: " + params.getJobId());
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
if(AppUtilities.isInteractive(pm) ){ //if the device is active
int wifiStrenght = WifiUtilities.getWifiStrengh(getApplicationContext());
Log.i(TAG, "wifi strengh ........... : " + wifiStrenght);
if(wifiStrenghtListener!=null){
if(wifiStrenght<4 && !AppUtilities.messageIsShowed){
wifiStrenghtListener.showSlowSignalOnTop(View.VISIBLE);
AppUtilities.messageIsShowed = true;
}else if(wifiStrenght>3 && AppUtilities.messageIsShowed){
wifiStrenghtListener.showSlowSignalOnTop(View.GONE);
AppUtilities.messageIsShowed = false;
}
}
}else{
cancelAllJobs();
Log.i(TAG, "job canceled........");
}
return false; // true if we're not done yet and we are going to run this on a thread
}
// If the job fails for some reason, return true from on the onStopJob to restart the job.
@Override
public boolean onStopJob(JobParameters params) {
return true;
}
public void cancelAllJobs() {
JobScheduler tm = (JobScheduler) getSystemService(Context.JOB_SCHEDULER_SERVICE);
tm.cancelAll();
}
public interface WifiStrenghtListener{
void showSlowSignalOnTop(int visible);
}
}
控制器订阅活动 .
public class WifiJobSchedulerController {
public void setWifiJobSchedulerControllerInstance(WifiJobScheduler.WifiStrenghtListener listener){
WifiJobScheduler.wifiStrenghtListener = listener;
}
}
最后，您需要实现接口并订阅活动 .
public class LoginActivity extends AppCompatActivity implements WifiJobScheduler.WifiStrenghtListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
//register wifistrenght status listener
new WifiJobSchedulerController().setWifiJobSchedulerControllerInstance(this);
}
@Override
public void showSlowSignalOnTop(int visible) {
TextView message = (TextView)findViewById(R.id.messageLogin);
message.setVisibility(visible);
}
}
