获取在前台post Oreo中打开的应用程序

import android.app.ActivityManager;
import android.app.ActivityManager.RunningAppProcessInfo;
import android.content.Context;

public class ForegroundAppHelper {

    public static String getForegroundApp(Context context) {
        ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        if (activityManager != null) {
            RunningAppProcessInfo foregroundProcessInfo = null;
            for (RunningAppProcessInfo processInfo : activityManager.getRunningAppProcesses()) {
                if (processInfo.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
                    foregroundProcessInfo = processInfo;
                    break;
                }
            }
            if (foregroundProcessInfo != null) {
                return foregroundProcessInfo.processName;
            }
        }
        return null;
    }
}