在android 5.0以上，如何判断当前应用是在前台还是后台

今天在做项目时遇到这个问题，本来很简单的，但是在Android 5.1 的系统上运行却出错了，在网上查找答案后发现原来是在android 5.0 之后getRunningTask（）方法被废弃，失效了。在网上查到的解决方法如下，已验证有效：

[java] view plain copy







private boolean isAppIsInBackground(Context context) {

boolean isInBackground = true;

ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);

if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT_WATCH) {

List<ActivityManager.RunningAppProcessInfo> runningProcesses = am.getRunningAppProcesses();

for (ActivityManager.RunningAppProcessInfo processInfo : runningProcesses) {

//前台程序

if (processInfo.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {

for (String activeProcess : processInfo.pkgList) {

if (activeProcess.equals(context.getPackageName())) {

isInBackground = false;

}

}

}

}

} else {

List<ActivityManager.RunningTaskInfo> taskInfo = am.getRunningTasks(1);

ComponentName componentInfo = taskInfo.get(0).topActivity;

if (componentInfo.getPackageName().equals(context.getPackageName())) {

isInBackground = false;

}

}

return isInBackground;

}