判断安卓应用处于前台或者后台

mContext = GuideApplication.getGuideApplication().getBaseContext();

public static boolean isBackground(Context context) {    ActivityManager activityManager = (ActivityManager) context            .getSystemService(Context.ACTIVITY_SERVICE);    List<ActivityManager.RunningAppProcessInfo> appProcesses = activityManager            .getRunningAppProcesses();    for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {        if (appProcess.processName.equals(context.getPackageName())) {            if (appProcess.importance != ActivityManager.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;}

其他人写法：

ActivityManager mActivityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE) ;    
  
//获得系统运行的进程  
List<ActivityManager.RunningAppProcessInfo> appList1 = mActivityManager  
        .getRunningAppProcesses();  
for (RunningAppProcessInfo running : appList1) {  
    System.out.println(running.processName);  
}  
System.out.println("================");  
  
//获得当前正在运行的service  
List<ActivityManager.RunningServiceInfo> appList2 = mActivityManager  
        .getRunningServices(100);  
for (ActivityManager.RunningServiceInfo running : appList2) {  
    System.out.println(running.service.getClassName());  
}  
  
System.out.println("================");  
  
//获得当前正在运行的activity  
List<ActivityManager.RunningTaskInfo> appList3 = mActivityManager  
        .getRunningTasks(1000);  
for (ActivityManager.RunningTaskInfo running : appList3) {  
    System.out.println(running.baseActivity.getClassName());  
}  
System.out.println("================");  
  
//获得最近运行的应用  
List<ActivityManager.RecentTaskInfo> appList4 = mActivityManager  
        .getRecentTasks(100, 1);  
for (ActivityManager.RecentTaskInfo running : appList4) {  
    System.out.println(running.origActivity.getClassName());  
    }