android - Cannot resolve symbol R after adding another xml file to my project -

as title , using 1 xml file on project activity_maps , , working fine , after adding info_window.xml , symbol r became red , don't know why , tried rebuilding project , nothing happened.

this activity_maps.xml :

<relativelayout xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:tools="http://schemas.android.com/tools"      android:layout_width="match_parent"      android:layout_height="match_parent"      tools:context=".mapactivity" >       <fragment xmlns:android="http://schemas.android.com/apk/res/android"           xmlns:tools="http://schemas.android.com/tools"           android:layout_width="match_parent"           android:layout_height="match_parent"           android:id="@+id/map"           android:name="com.google.android.gms.maps.supportmapfragment"/>  </relativelayout> 

this info_window.xml :

<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:orientation="horizontal">     <imageview         android:id="@+id/imageview1"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:src="@drawable/sefleticon"/>      <linearlayout         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:orientation="vertical">         <textview             android:id="@id/tv_place"             android:layout_width="wrap_content"             android:layout_height="wrap_content"             android:textsize="25sp"             android:textstyle="bold" />         <textview             android:id="@id/tv_men"             android:layout_width="wrap_content"             android:layout_height="wrap_content" />         <textview             android:id="@id/tv_women"             android:layout_width="wrap_content"             android:layout_height="wrap_content" />         <textview             android:id="@id/tv_like"             android:layout_width="wrap_content"             android:layout_height="wrap_content" />     </linearlayout>  </linearlayout> 

the both of xml files in res/layout

in second xml :

change linearlayout linearlayout

and in textview's change android:id="@id/your_id" android:id="@+id/your_id"