v4支持库通知不起作用

Question

我发现一个奇怪的行为与Android支持库v4。只有当我们为通知设置了小图标时，通知才会起作用，否则通知将不会发布到状态栏上。示例代码是代码张贴在下面请看看。任何人都可以解释为什么这个怪异的行为

// below code will not post any notification 

Intent intent = new Intent(context, MainActivity.class); 
PendingIntent pIntent = PendingIntent.getActivity(context, 0, intent, 0); 
Notification n = new Builder(context.getApplicationContext()) 
       .setContentTitle("simple notification title") 
       .setContentText("simple message") 
       .setContentIntent(pendingIntent) 
       .setAutoCancel(true) 
       .addAction(R.drawable.ic_launcher, "Call", pIntent) 
       .addAction(R.drawable.ic_launcher, "More", pIntent) 
       .addAction(R.drawable.ic_launcher, "And more",pIntent).build(); 
NotificationManager notificationManager =(NotificationManager) context.getApplicationContext().getSystemService(Context.NOTIFICATION_SERVICE); 
              notificationManager.notify(0, n); 

//以下代码将发布通知

Intent intent = new Intent(context, MainActivity.class); 
PendingIntent pIntent = PendingIntent.getActivity(context, 0, intent, 0); 
Notification n = new Builder(context.getApplicationContext()) 
       .setContentTitle("simple notification title") 
       .setContentText("simple message") 
       .setContentIntent(pendingIntent) 
       .setAutoCancel(true) 
      //this below one line piece of code is making difference 
       .setSmallIcon(R.drawable.ic_launcher) 
       .addAction(R.drawable.ic_launcher, "Call", pIntent) 
       .addAction(R.drawable.ic_launcher, "More", pIntent) 
       .addAction(R.drawable.ic_launcher, "And more",pIntent).build(); 


NotificationManager notificationManager =(NotificationManager) context.getApplicationContext().getSystemService(Context.NOTIFICATION_SERVICE); 
              notificationManager.notify(0, n); 

Answer 1

在http://developer.android.com/guide/topics/ui/notifiers/notifications.html文档中明确指出其通知内容是必需的，这是可选的。

需要一个小图标。