Android开发之ActivityManager获取系统信息

1.判断指定的service是否在运行

 public static boolean isServiceRunning(Context ctx, String serviceName) {
         ActivityManager am = (ActivityManager) ctx
                 .getSystemService(Context.ACTIVITY_SERVICE);
         List< RunningServiceInfo > runningServices = am.getRunningServices(200); // 获取运行的所有service，100一般可以获取到所有的service.
         for ( RunningServiceInfo runningServiceInfo : runningServices ) {
             String className = runningServiceInfo.service.getClassName();    //获取到运行服务的类名
             if ( className.equals(serviceName) ) { // 假如在运行的service中含有传入的service名称，返回true
                 return true;
             }
         }
         return false;
     }

2.获取到系统运行的进程数

 public static int getRunningTaskCount(Context context) {
         ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
         List< ActivityManager.RunningAppProcessInfo > runningAppProcesses = am.getRunningAppProcesses();
         return runningAppProcesses.size();
     }

3.获取设备可用内存

 public static long getAvaliMem(Context context) {
         ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
         ActivityManager.MemoryInfo outInfo = new ActivityManager.MemoryInfo();
         am.getMemoryInfo(outInfo);
         return outInfo.availMem;
     }

4.获取设备总内存

 public static long getTotalMem(Context context) {
         ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
         ActivityManager.MemoryInfo outInfo = new ActivityManager.MemoryInfo();
         am.getMemoryInfo(outInfo);
         return outInfo.totalMem;
     }