Question

我对Android比较陌生，所以我在这里很困惑......

我希望每天在特定时间触发通知。

我使用Calendar类设置每天触发通知的时间，并使用AlarmManager设置重复任务。

问题是，在最初启动应用程序时触发通知，而不是在Calendar对象中配置的预定义时间触发。当我在调试模式下运行时，我看到我转到了setExact方法。

我还创建了一个接收器来处理通知本身，并在单击通知时打开MainActivity。

MainActivity.java

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        .
        .
        .
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.HOUR_OF_DAY, 8);
        calendar.set(Calendar.MINUTE, 30);
        calendar.set(Calendar.SECOND, 0);
        Intent intent = new Intent(this, NotificationReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 100, intent, PendingIntent.FLAG_UPDATE_CURRENT);
        AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
        if (Build.VERSION.SDK_INT < 19)
            alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);
        else
            alarmManager.setExact(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);

    }

NotificationReceiver.java

public class NotificationReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        NotificationManager manager = (NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE);

        Intent mainIntent = new Intent(context, MainActivity.class);
        mainIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

        PendingIntent pendingIntent = PendingIntent.getActivity(context, 100, mainIntent, PendingIntent.FLAG_UPDATE_CURRENT);
        Notification.Builder builder = new Notification.Builder(context);
        builder.setContentTitle("This is the title")
                .setContentText("This is the text")
                .setContentIntent(pendingIntent)
                .setSmallIcon(R.drawable.deal_icon);

        Notification notification = builder.build();
        notification.defaults = Notification.DEFAULT_VIBRATE | Notification.DEFAULT_SOUND;
        notification.flags |= Notification.FLAG_AUTO_CANCEL;

        manager.notify(100, notification);
    }
}

的manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.goldbox.goldboxdeals">

    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="com.android.alarm.permission.SET_ALARM"/>
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:name="com.sample.sample1.ApplicationHelper"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity" android:screenOrientation="portrait">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

        <receiver android:name=".NotificationReceiver" android:enabled="true" android:exported="false">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
                <action android:name="android.intent.action.QUICKBOOT_POWERON" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </receiver>
    </application>

Answer 1

Calendar.getInstance()会返回当前当地时间的日历。然后，您可以根据今天的日期设置时间。计划警报时，日期可能是过去的日期。然后系统会立即触发警报。

我相信你应该使用setRepeating()。您可以设置触发/间隔时间。请注意，您的应用甚至设备本身并不一定都在运行。

通知立即触发，而不是在我希望触发时

1 个答案: