activate gearVR at runtime

As lot of users , i would like to create a first UI selection screen in order to configure my scene, then apply parameters and activate a GearVR view.
i ve tried few tests.

if VR mode supported in player setting is ON, Android asks to plug the gear headset at the begining. I added “None” and “Oculus” in sdk’s section. the order is not working. in my case
if i put only “none” sdk with VRmodesupported = true, the app is launched without vr but I can’t use the VRSetting.LoadDeviceByName in script to switch to gear. it doesn’t work.

I tried VRmodesupported = false in the players settings, then launch app and set VRSetting.enable=true at runtime trought script but it doesn’t work also. so with this configuration, i tried to loadDeviceByname before enabling VRSetting and nothing appends.

so I don’t know if it’s possible to do that.

Unity : 5.5.0 64bits
phone : galaxy s6
android : 6.0.1
project : from scratch. only one script to manage vrmode
oculus app 2.28.3 installed on phone

have Got solution For this Bcoz cardboard run-time work But Gear vr not Work.