-1

您好，我正在尝试在执行时创建一个示例应用程序，它将带您回到主屏幕，运行后台进程并显示 toast points。

我认为我需要在后台进程中使用一个单独的线程来完成我需要的任何工作。这是我的主要活动的代码（BackGroundPrcessingExampleActivity）：

enter code here
public class BackGroundProcessExampleActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        try {

            Intent myIntent = new Intent(this, MyService.class);
            startService(myIntent);

            moveTaskToBack(false);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

这是来自“MyService.java”的代码：

enter code here
public int onStartCommand(Intent intent, int flags, int startId) {

    Toast.makeText(getBaseContext(), "Service is started!", 1).show();

    myHandler = new Handler() {

        @Override
        public void handleMessage(Message msg) {

            super.handleMessage(msg);


                Toast.makeText(getBaseContext(), "Hello!",
                        Toast.LENGTH_SHORT).show();
        }
    };



    Runnable runnable = new Runnable() {
        @Override
        public void run() {



            while (true) {

                try {               

                    Thread.sleep(2);

                    myHandler.sendEmptyMessage(0);

                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    };
    new Thread(runnable).start();

    return super.onStartCommand(intent, flags, startId);
}

我遇到的问题是没有出现 Toast 消息。我可以设置断点并查看它正在单步执行代码，但没有出现任何消​​息。我认为可能是上下文不正确？我需要 UI 的上下文（BackGroundPRcessExampleActivity）吗？任何帮助表示赞赏，在此先感谢。

D

4

2 回答 2

0

在回复的帮助下，这最终对我有用。添加了通知代码。

    @Override
public int onStartCommand(Intent intent, int flags, int startId) {

    final NotificationManager notificationManager = (NotificationManager) 
            getSystemService(NOTIFICATION_SERVICE);

    // Create Notifcation
    final Notification notification = new Notification(R.drawable.ic_launcher,
        "A new notification", System.currentTimeMillis());

    // Cancel the notification after its selected
    notification.flags |= Notification.FLAG_AUTO_CANCEL;
    //
    notification.number += 1;

    // Specify the called Activity
    Intent intent2 = new Intent(this, NotificationReceiver.class);

    Toast.makeText(getApplicationContext(), "Service is started!", 1)
            .show();

    PendingIntent activity = PendingIntent.getActivity(this, 0, intent2, 0);
    notification.setLatestEventInfo(this, "This is the title",
        "This is the text", activity);


    myHandler = new Handler();

    Runnable runnable = new Runnable() {
        @Override
        public void run() {
            int i = 0;

            while (true) {
                final int x = i++;

                try {
                    Thread.sleep(500);
                } catch (InterruptedException e1) {
                    e1.printStackTrace();
                }

                myHandler.post(new Runnable() {

                    @Override
                    public void run() {

                        try {
                            Toast.makeText(getApplicationContext(),
                                    "Hello!" + String.valueOf(x),
                                    3).show();

                            if(x == 100)
                                notificationManager.notify(0, notification);
                            Thread.sleep(1);

                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }
                });
            }
        }
    };
    new Thread(runnable).start();

谢谢大家的帮助。

D

于 2012-04-13T11:41:38.993 回答
0

试试看 -

public int onStartCommand(Intent intent, int flags, int startId) {
Handler mHandler = new Handler();
Toast.makeText(getApplicationContext(), "Service is started!", 1).show();

Runnable runnable = new Runnable() {
    @Override
    public void run() {
        while (true) {
            try { 
                Thread.sleep(5000);

                mHandler.post(new Runnable() {
              @Override
               public void run() {
                        Toast.makeText(getApplicationContext(), "Hello!", Toast.LENGTH_LONG).show();
                  }
               });
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
};
new Thread(runnable).start();

return super.onStartCommand(intent, flags, startId);

}

于 2012-04-12T16:15:05.520 回答