Issue with Http.post in apk

Ionic Framework ionic-v3
1

i’m facing difficulty while setting root in http post for login and to move on to next page.

this.http.post(url, JSON.stringify(body), {headers: this.headers}).subscribe(
        data => {
          this.navCrtl.setRoot(homepage);
        },
        error => {
          console.log(JSON.stringify(error.json()));
        }
      );

the above code works fine in browser but not in android device.

Thanks in Advance.