Android TaskStackBuilder和工具栏图标闪烁

我的通知代码：

NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this)
    .setSmallIcon(R.drawable.ic_launcher)
    .setContentTitle(getResources().getString(R.string.app_name))
    .setContentText("test")
    .setAutoCancel(true)
    .setTicker("Powiadomienie: test");

TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);

Intent ia = new Intent(this, ActivityA.class);
Intent ib = new Intent(this, ActivityB.class);
Intent ic = new Intent(this, ActivityC.class);

stackBuilder.addNextIntent(ia);
stackBuilder.addNextIntent(ib);
stackBuilder.addNextIntent(ic);

mBuilder.setContentIntent(stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT));

mNotificationManager.notify(1, mBuilder.build());

活动顺序如下： 活动A->活动B->活动C

当显示ActivityC堆栈时，它就像代码中一样是从一端构建的。返回按钮显示ActivityB和ActivityA

在视频中显示发生了什么：

当显示最后一个活动（ActivityA）时，工具栏图标显示标准图标，之后显示活动图标。此图标在AndroidManifest.xml中设置

<activity android:name="ActivityA" android:icon="@drawable/ic_launcher2"></activity>

<activity android:parentActivityName=".ActivityA" android:name="ActivityB" android:icon="@drawable/ic_launcher2">
    <meta-data 
        android:name="android.support.PARENT_ACTIVITY"
        android:value=".ActivityA" />
</activity>

<activity android:parentActivityName=".ActivityB" android:name="ActivityC" android:icon="@drawable/ic_launcher2">
    <meta-data 
        android:name="android.support.PARENT_ACTIVITY"
        android:value=".ActivityB" />
</activity>