Two Routers On One Network

i have an adsl modem with 4 ethernet ports and it does NOT have WiFi, we will call this Router A.....as Router A has no Wifi i bought another router which has wifi,4 ethernet LAN ports,1 WAN port and it is NOT A MODEM, we call this device Router B.

i have the network setup....i set the IP of router A to 192.168.1.1,ran an ethernet cable from it to Router B's WAN port and assigned it IP 192.168.1.2 to access internet, and set Router B's local IP to 192.168.0.1....Router A assigns IP 192.168.1.xxx whereas Router B assigns 192.168.0.xxx to the devices that connect to it.....so now,internet works in any way i connect to any of the routers,but file sharing does not work between the two routers. for example if i have one pc connected to one router and another pc connected to the other router,i cannot share files between them.....

what is the solution to this problem?