When I'm trying to run "xterm" in termux, it says failed to open display : :0. Why so?

It seems there is some kind of firewall,which is blocking the connection. I was unable to solve this problem. But I found a work around.
1. Entered a terminal with root privilage.
(E.g : used command su in a terminal emulator)
2. Created a 2nd loop back network by ifconfig
(E.g : ifconfig lo:0 127.0.0.2 netmask 255.0.0.0 up)
3. Fortunately "XSERVER XSDL" recognized this new network without any complain(Never thought it could detect such a weird network).
4. At last set my display to new server from my chroot environment as shown in XSERVER welcome screen.
export DISPLAY=127.0.0.2:1 startfluxbox ( or any xclient program, now everything runs fine)

Note 1: Each time my phone is restarted, I've to create the loopback network again. There might be some .rc files for adding startup scripts on android too. But I never bothered changing them(because I don't restart my phone often).
Note 2: I would really appreciate a true solution though(better if it works without root) because my method can't be applied on a non-rooted phone. So people with this problem but without a rooted phone can't use xserver untill someone finds another solution.