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通过编程取消(和隐藏)Android通知

notificationmanager android-notifications android-service notifications android

CybeX · 技术社区 · 6 年前

我有一个与通知(系统)一起运行的服务。当服务停止(和/或应用程序停止)时,应取消通知(即不再显示在状态栏上)。

通过提供 Android Dev guide of Notifications ,我没有找到有关如何关闭通知的任何信息。

这样,我发现了许多问题。

1。

总结 @nipun.birla 的 answer 如何取消Android通知:

到 取消通知 按顺序尝试:

NotifcationManager.cancel(int) 具有 notificationID
NotificationManager.cancel(String, int) 具有 通知通知号 和 notificationTag
NotificationManager.cancelAll() 作为最后的尝试

然而,没有提到的是,如果这些都不起作用,应该怎么做。

2。

一个人应该用 cancelAll suggestion

三。

This SO thread 包含已启动的服务示例的一个很好的示例,其中关联通知在服务生命周期中实现(在该生命周期中通知也被终止)-请参见此处了解 Started Service details

4。

Here 建议删除 PendingIntent 与通知关联

5。

另外几个问题和解决方案反映了上述相同的信息: 见 this 和 this 还有更多…

6。

安 very interesting question and solution 在状态栏中以编程方式隐藏通知图标时

我的问题

到目前为止,这应该是相当明显的 ,我的通知不会取消自己要求的。

实施:

请参阅下面的完整实现,尽管我将发布助手类和核心函数的一般用法

-创建通知

private Context context;
private NotificationManager notificationManager;
private NotificationChannel notificationChannel;
private NotificationCompat.Builder notificationBuilder;

public NotificationHelper(Context context) {
    this.context = context;

    // Init notification

    // onNotificationCreate()
    {

        // get notification manager system service
        notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            // Create notification channel
            createNotificationChannel();

            //Register notification channel with notification manager
            notificationManager.createNotificationChannel(notificationChannel);
        }

    }

    // Init Notification Builder

    // createNotificationChannel() 
    {
        Log.d(TAG, "createNotificationChannel: Creating notification channel");

        // Define notification channel ID, Channel Name and description
        String channelName = BuildConfig.FLAVOR.concat(" Notifier");
        String channelDescription = context.getString(R.string.notification_description);

        // Create notification channel
        notificationChannel = new NotificationChannel(channelId, channelName, NotificationManager.IMPORTANCE_LOW);
        // Set description of notification channel
        notificationChannel.setDescription(channelDescription);
    }
}

这是由 new NotificationHelper(getApplicationContext) 上下文是 Application 上下文使用 它还用作许多其他函数的上下文 )

帮助类背后的方法是简单地使用 method chaining 允许更多 眼烛光 创建、修改和取消通知的方法。

-通知帮助程序用法:

设置通知 contentText 通过呼叫 setTextContent(String) :

public NotificationHelper setTextContent(String text){
    notificationBuilder.setContentText(text);
    return this;
}

设置 contentTitle by`settitle(字符串):

public NotificationHelper setTitle(String format) {
    notificationBuilder.setContentTitle(format);
    return this;
}

设置 smallIcon (状态图标)通过调用 setStatusIcon(int) :

public NotificationHelper setStatusIcon(int res_id) {
    notificationBuilder.setSmallIcon(res_id);
    return this;
}

最后,通过以下方式更新通知以显示结果设置:

public void update() {
    Log.d(TAG, "update: Updating notification");
    Notification notification = notificationBuilder.build();

    // Set notification flags
    notification.flags |= Notification.FLAG_NO_CLEAR;
    notification.flags |= Notification.FLAG_ONGOING_EVENT;
    notification.flags |= Notification.FLAG_FOREGROUND_SERVICE;

    // Notify update
    notificationManager.notify(TAG, notificationId, notification);
}

-取消通知

如预期的那样,取消通知和调用 cancelNotification() :

public void cancelNotification() {
    Log.d(TAG, "cancelNotification: Cancelling notification");
    notificationManager.cancel(TAG, notificationId);
}

但是,这对取消通知没有影响。

取消通知时 ,以下事件发生在取消之前。

应用程序退出已启动。
这个 Bound Service 未绑定-确保没有客户端绑定到它。 unbindService 被调用 getApplicationContext() 关于拥有的上下文 unbindService(ServiceConnection) 使用相同的 ServiceConnection 与原始绑定。

完成所有这些操作后,通知仍然有效。

我试过什么

notificationManger.cancel(int)
notificationManger.cancel(String, int)
notificationManger.cancelAll

这不起作用,所以我有了创意:

此外: 创建单独的 NotificationManager 方法发布这些更新(即此处没有设置标志,但相同 notificationmanager 使用)

public void updateCancelable() {
    Log.d(TAG, "update: Updating notification to cancel");
    Notification notification = notificationBuilder
            .setContentIntent(null)
            .setOngoing(false)
            .setAutoCancel(true)
            .build();
    // Notify update
    notificationManager.notify(TAG, notificationId, notification);
}

清除 setContentIntent() 通过呼叫 setContentIntent(null) 并重新通知更新
我还尝试创建一个新的通知 cancelable 具有 setAutoCancel(true) ,并设置 ongoing state 具有 setOngoing(false) 并重新通知更新

这也无济于事。有什么我可能找不到的吗?

我还应该提到:在调试我的应用程序时,我注意到当我退出应用程序时(使绑定服务停止并调用 取消通知() ,应用程序不应该再运行了,尽管Android Studio仍然保持一个活动的调试会话打开,就像应用程序仍在运行时所期望的那样。不确定这是否与它有关。

NotificationHelper类(完整实现)

import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.os.Build;
import android.support.annotation.RequiresApi;
import android.support.v4.app.NotificationCompat;
import android.util.Log;

import com.connectedover.BuildConfig;
import com.connectedover.R;
import com.connectedover.listeners.NotificationUpdateListener;

/**
 * Class aimed at providing helper method for creating, maintaining and destroying notifications in conjunction with {@link de.blinkt.openvpn.core.OpenVPNService}
 *
 * @author cybex
 * @since 1.5.1
 */
public class NotificationHelper implements NotificationUpdateListener {

    private static final String TAG = NotificationManager.class.getSimpleName();
    private static final String channelId = BuildConfig.APPLICATION_ID.concat(".").concat(TAG);
    private static final int notificationId = 42;

    private Context context;
    private NotificationManager notificationManager;
    private NotificationChannel notificationChannel;

    private NotificationCompat.Builder notificationBuilder;

    public NotificationHelper(Context context) {
        this.context = context;

        // Init notification
        onNotificationCreate();

        // Init Notification Builder
        createBasicNotification();
    }

    /**
     * Initialize {@link NotificationChannel} and register channel with {@link NotificationManager} service if API is Android Orea (API 26 or higher), else initializes the notification manager
     */
    private void onNotificationCreate() {
        Log.d(TAG, "onNotificationCreate: Initializing notification helper");

        // get notification manager system service
        notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            // Create notification channel
            createNotificationChannel();

            //Register notification channel with notification manager
            notificationManager.createNotificationChannel(notificationChannel);
        }
    }

    /**
     * Creates a notification channel required by devices running Android SDK 26 and higher.
     * The notification  channel is set to {@link NotificationManager#IMPORTANCE_LOW} which should have no sound and appear right at the top of the status bar
     */
    @RequiresApi(api = Build.VERSION_CODES.O)
    private void createNotificationChannel() {
        Log.d(TAG, "createNotificationChannel: Creating notification channel");

        // Define notification channel ID, Channel Name and description
        String channelName = BuildConfig.FLAVOR.concat(" Notifier");
        String channelDescription = context.getString(R.string.notification_description);

        // Create notification channel
        notificationChannel = new NotificationChannel(channelId, channelName, NotificationManager.IMPORTANCE_LOW);
        // Set description of notification channel
        notificationChannel.setDescription(channelDescription);
    }

    /**
     * Creates a basic notification using {@link android.support.v4.app.NotificationCompatBuilder} for use throughout the application
     */
    private void createBasicNotification() {
        // Instantiate Notification Builder
        notificationBuilder = new NotificationCompat
                .Builder(context, channelId)
                .setContentTitle(context.getString(R.string.app_name))
                .setSmallIcon(R.drawable.ic_logo_disconnected)
                .setWhen(System.currentTimeMillis())
                .setAutoCancel(false)
                .setOngoing(true);
    }

    /**
     * Set the pending intent of a clickable {@link android.app.Notification} held by {@link NotificationHelper#notificationBuilder}
     * @param pendingIntent Pending intent to connect to activity
     * @return returns an instance of {@link NotificationHelper}
     */
    public NotificationHelper setPendingIntent(PendingIntent pendingIntent){
        Log.d(TAG, "setPendingIntent: Setting notification Pending intent");
        notificationBuilder.setContentIntent(pendingIntent);
        return this;
    }

    /**
     * Updates the notification which is displayed for the user.
     */
    public void update() {
        Log.d(TAG, "update: Updating notification");
        Notification notification = notificationBuilder.build();

        // Set notification flags
        notification.flags |= Notification.FLAG_NO_CLEAR;
        notification.flags |= Notification.FLAG_ONGOING_EVENT;
        notification.flags |= Notification.FLAG_FOREGROUND_SERVICE;

        // Notify update
        notificationManager.notify(TAG, notificationId, notification);
    }

    /**
     * Updates the notification {@link NotificationHelper#notificationBuilder} with new text and displays it to the user
     *
     * @param text new text to display
     * @return returns current {@link NotificationHelper} instance for method chaining.
     */
    public NotificationHelper setTextContent(String text){
        notificationBuilder.setContentText(text);
        return this;
    }

    @Override
    public void onUpdate(String update) {
        Log.d(TAG, "onUpdate: updating notification via callback");
        this.setTextContent(update)
                .update();
    }

    /**
     * Sets a new icon for the notification displayed to the user
     * @param res_id icon resource
     * @return current instance
     */
    public NotificationHelper setLargeIcon(int res_id) {
        notificationBuilder.setLargeIcon(ImageUtils.toBitmap(context, res_id));
        return this;
    }

    /**
     * Sets a new icon for the notification displayed to the user show in the status bar (i.e. the small icon)
     * @param res_id icon resource
     * @return current instance
     */
    public NotificationHelper setStatusIcon(int res_id) {
        notificationBuilder.setSmallIcon(res_id);
        return this;
    }

    public NotificationHelper setTitle(String format) {
        notificationBuilder.setContentTitle(format);
        return this;
    }

    /**
     * Cancels the application notification
     */
    public void cancelNotification() {
        Log.d(TAG, "cancelNotification: Cancelling notification");
        notificationManager.cancelAll();
    }
}

1 回复 | 直到 6 年前

CommonsWare 6 年前

如果你想用你的 Notification 作为前台服务的一部分,不要直接操作标志,而是使用 startForeground() 和 stopForeground() 对你 Service .