如何在通知中连续显示4个按钮

Question

3按钮没问题，但没有显示。

根本不可能吗？

编辑：

我正在添加4个按钮：

    builder.addAction(R.drawable.av_previous, "", PendingIntent.getBroadcast(context, 1, new Intent(context, NotificationPlayerControlReceiver.class), PendingIntent.FLAG_CANCEL_CURRENT));
    builder.addAction(R.drawable.av_play, "", PendingIntent.getBroadcast(context, 2, new Intent(context, NotificationPlayerControlReceiver.class), PendingIntent.FLAG_CANCEL_CURRENT));
    builder.addAction(R.drawable.av_next, "", PendingIntent.getBroadcast(context, 4, new Intent(context, NotificationPlayerControlReceiver.class), PendingIntent.FLAG_CANCEL_CURRENT));
    builder.addAction(R.drawable.cancel, "", PendingIntent.getBroadcast(context, 5, new Intent(context, NotificationPlayerControlReceiver.class), PendingIntent.FLAG_CANCEL_CURRENT));

显示前三个按钮，最后一个按钮不显示