Unfortunately most wireless, RF-technology bike computers (like the Strada Wireless) can not be used in conjunction with HID or similar high-power lights, as the lights generate too strong a field of electrical interference for the computer to consistently pick up the wireless RF signal.
One potential solution is to separately the light and the computer head unit as much as possible on the handlebar, to see if you can get the computer head unit outside of the range of the light's field of interference. A few inches may be enough, but this will vary based on the strength of the field generated by the light.
If you're using the light and computer together frequently, you'll likely want to run the a wired equivalent version, such as the Strada (CC-RD100).