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通知contentView和bigContentView在Android 7中为空

remoteview lockscreen notifications android

target33 · 技术社区 · 8 年前

我的应用程序的一部分包括一个自定义锁屏,它需要像普通安卓锁屏一样显示通知。

在Android 6之前,一切都很好,我使用NotificationListenerService来检索通知contentView和bigContentView(RemoteViews)。我在我的自定义RecyclerView适配器上使用它们来创建通知列表,其中包含服务列出的相同通知:

//this is called by NotificationListenerService
@Override
public void onNotificationPosted(StatusBarNotification sbn) {
    AddNotification(sbn);
}

/**
* Add notification into recycleview
* @param sbn notification to add
*/
private void AddNotification(StatusBarNotification sbn)
{
    Notification notification = sbn.getNotification();

    if(notification==null) return;

    if(notification.bigContentView!=null) {
        //apply bigContentView to my recycleview list notification view
        myListView.notificationview = notification.bigContentView.apply(myContext(), myNotificationLayout);
    }
    else if(notification.contentView!=null) {
        //apply contentView to my recycleview list notification view
        myListView.notificationview = notification.contentView.apply(myContext(), myNotificationLayout);
    }

    //notify recycleview of a new item inserted
    notifyItemInserted(0);
}

这在Android 7中不再可能,因为从Android N开始(如Android文档中所述), contentView bigContentView可以为null(实际上是)。这些非常有用,因为您可以复制通知视图,其中还可以包含一些复杂的操作控件(例如媒体播放器通知,带有播放/暂停/停止控件):

media player notification

如何复制RemoteView行为?是否可以检索所有通知信息(图形、文本、图标、意图等)?

2 回复 | 直到 8 年前

wgm 7 年前

我有一个更好的解决方案:

@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
public static RemoteViews getBigContentView(Context context, Notification notification)
{
    if(notification.bigContentView != null)
        return notification.bigContentView;
    else if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
        return Notification.Builder.recoverBuilder(context, notification).createBigContentView();
    else
        return null;
}

public static RemoteViews getContentView(Context context, Notification notification)
{
    if(notification.contentView != null)
        return notification.contentView;
    else if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
        return Notification.Builder.recoverBuilder(context, notification).createContentView();
    else
        return null;
}

每当你提及 Notification.contentView ,只需打电话 getContentView(...) getBigContentView(...) Notification.bigContentView . 您的代码将支持android nougat+,以及所有android版本。

修改后, AddNotification 将是这样:

/**
 * Add notification into recycleview
 *
 * @param sbn notification to add
 */
private void AddNotification(StatusBarNotification sbn)
{
    Notification notification = sbn.getNotification();

    if (notification == null) return;

    RemoteViews remoteViews = getBigContentView(myContext(), notification);
    if(remoteViews == null)
        remoteViews = getContentView(myContext(), notification);

    if (remoteViews != null)
    {
        //apply bigContentView to my recycleview list notification view
        myListView.notificationview = remoteViews.apply(myContext(), myNotificationLayout);
    }

    //notify recycleview of a new item inserted
    notifyItemInserted(0);
}

target33 8 年前

这就是说,这里唯一的解决方案是使用与原始通知相同的信息重新创建Remoteview(如果希望同时具有压缩和扩展版本,则需要两个)。为此,需要从捆绑通知中提取信息 extras

Android N notification design