Using UsageStatsManager to get the foreground app

Question

I'm trying to use UsageStatsManager to get the foreground app on a Nexus 5 with Marshmallow. I remember it used to work, but for some reason I'm getting null strings for package/class names now.

Here's my implementation

public String[] getForegroundPackageNameClassNameByUsageStats() {
    String packageNameByUsageStats = null;
    String classByUsageStats = null;
    if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { 
        UsageStatsManager mUsageStatsManager = (UsageStatsManager)getSystemService("usagestats");                       
        final long INTERVAL = 1000;
        final long end = System.currentTimeMillis();
        final long begin = end - INTERVAL;
        final UsageEvents usageEvents = mUsageStatsManager.queryEvents(begin, end);
        while (usageEvents.hasNextEvent()) {
            UsageEvents.Event event = new UsageEvents.Event();
            usageEvents.getNextEvent(event);
            if (event.getEventType() == UsageEvents.Event.MOVE_TO_FOREGROUND) {
                packageNameByUsageStats = event.getPackageName();
                classByUsageStats = event.getClassName();
                Log.d(TAG, "packageNameByUsageStats is" + packageNameByUsageStats + ", classByUsageStats is " + classByUsageStats);
            }
        }
    }
    return new String[]{packageNameByUsageStats,classByUsageStats};
}

For some reason, it doesn't go into the while loop, i.e. usageEvents.hasNextEvent() is false. Because of this, it returns null package/class names.

Any idea what I'm doing wrong?

Thanks.

Answer 1

OK, so I found that once I set the interval to 10000 instead of 1000, it works. Apparently a 1s interval is too small.