Question

我正在制作一个警报应用程序，它将通知用户提供的时间。我从我的片段MyAlarm调用了一个类TimepickerFragment，但它没有传递给MyAlarm类。

以下是我片段中的代码：

public class TimepickerFragment extends Fragment {

Button SetTime;
TimePicker timePicker;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    return inflater.inflate(R.layout.timepickerfragment,null);
}

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

    timePicker = (TimePicker) view.findViewById(R.id.timePicker);

    SetTime = (Button) view.findViewById(R.id.settime);
    SetTime.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            Calendar calendar = Calendar.getInstance();

            calendar.set(
                    calendar.get(Calendar.YEAR),
                    calendar.get(Calendar.MONTH),
                    calendar.get(Calendar.DAY_OF_MONTH),
                    timePicker.getCurrentHour(),
                    timePicker.getCurrentMinute(),
                    0

            );

            setAlarm(calendar.getTimeInMillis());

            Fragment fragment = null;
            fragment = new Room1Fragment();
            FragmentManager fragmentManager = getFragmentManager();
            FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
            fragmentTransaction.replace(R.id.screen_area, fragment);
            fragmentTransaction.addToBackStack(null);
            fragmentTransaction.commit();

        }



        private void setAlarm(long timeInMillis) {

            AlarmManager alarmManager = (AlarmManager) getActivity().getSystemService(Context.ALARM_SERVICE);


            Intent intent = new Intent (getActivity(), MyAlarm.class);

            PendingIntent pendingIntent = PendingIntent.getBroadcast(getActivity(), 0 , intent, 0);


            alarmManager.setRepeating(AlarmManager.RTC , timeInMillis, AlarmManager.INTERVAL_DAY, pendingIntent);

            Toast.makeText(getActivity(), "Alarm is set", Toast.LENGTH_SHORT).show();

        }
    });


}

}

它应该传递给这个类：

    public class MyAlarm extends WakefulBroadcastReceiver {


    @Override
    public void onReceive(Context context, Intent intent) {

        Toast.makeText(context, "MyAlarm Working", Toast.LENGTH_SHORT).show();

        intent = new Intent(context, MyService.class);
        context.startService(intent);



    }
}

这是我的清单文件：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.haziqnaeem.settimer2">

<uses-permission android:name="android.permission.VIBRATE"/>
<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

    <receiver
        android:name=".MyAlarm"
        android:enabled="true"
        android:exported="true" />

    <service
        android:name=".MyService"
        android:enabled="true"
        android:exported="true"></service>
</application>

需要帮助

Answer 1

您还必须在清单文件中声明您的MyAlarm类，如下所示

<receiver
        android:name=".MyAlarm"
        android:process=":remote" />

具有以下权限

<uses-permission android:name="android.permission.WAKE_LOCK"/>
<uses-permission android:name="android.permission.VIBRATE"/>

Answer 2

如果我理解你很好，你想要的是，时间到了，你的设备会向用户发出警报，但是类MyAlarm它是一个WakefulBroadcastReceiver，它是：“实现接收设备唤醒事件的BroadcastReceiver，然后将工作传递给服务，同时确保设备在过渡期间不会重新入睡“==＆gt;来自官方文档。

现在，您已经设置了AlarmManager，因此，在pendingIntent午餐中，一个例如Intent服务的例子将触发声音或通知或类似的东西，但是知道AlarmManager实际上不会为您打开屏幕，因此不会调用WakefulBroadcastReceiver，您可以使用带有唤醒锁的PowerManager。并且还要知道WakefulBroadcastReceiver在API级别26.1.0中已被弃用。

如何从片段中调用类

2 个答案: