ActivityManager mActivityManager = (ActivityManager)getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
List<ActivityManager.RunningTaskInfo> list = mActivityManager.getRunningTasks(1);
if (list.size() > 0) {
String className = list.get(0).topActivity.getClassName();
}
---
AndroidManifest.xml で、
<uses-permission android:name="android.permission.GET_TASKS"/>