Android getTopActivity的步骤

使用如下方法可以获得top activity 的name

public String getTopActivityPackageName(Context context) {    String topActivityPackage = null;    ActivityManager activityManager = (ActivityManager) (context            .getSystemService(android.content.Context.ACTIVITY_SERVICE));    List<RunningTaskInfo> runningTaskInfos = activityManager            .getRunningTasks(1);    if (runningTaskInfos != null) {        ComponentName f = runningTaskInfos.get(0).topActivity;        topActivityPackage = f.getPackageName();    }    return topActivityPackage;}