Android 判断app是否在前台还是在后台运行-白红宇

Android 判断app是否在前台还是在后台运行，直接看代码，可直接使用。
[java]
 public static boolean isBackground(Context context) {   
         ActivityManager activityManager = (ActivityManager) context   
                 .getSystemService(Context.ACTIVITY_SERVICE);   
         List<RunningAppProcessInfo> appProcesses = activityManager   
                 .getRunningAppProcesses();   
         for (RunningAppProcessInfo appProcess : appProcesses) {   
             if (appProcess.processName.equals(context.getPackageName())) {   
                 /*  
                 BACKGROUND=400 EMPTY=500 FOREGROUND=100  
                 GONE=1000 PERCEPTIBLE=130 SERVICE=300 ISIBLE=200  
                  */   
                 Log.i(context.getPackageName(), "此appimportace ="   
                         + appProcess.importance   
                         + ",context.getClass().getName()="   
                         + context.getClass().getName());   
                 if (appProcess.importance != RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {   
                     Log.i(context.getPackageName(), "处于后台"   
                             + appProcess.processName);   
                     return true;   
                 } else {   
                     Log.i(context.getPackageName(), "处于前台"   
                             + appProcess.processName);   
                     return false;   
                 }   
             }   
         }   
         return false;   
     }   