So... since 2018/03/31 we have a treble compatible vendor image without any problems so far.
To test a Generic System Image (GSI), you need the following:
- Flash the last TWRP recovery build: https://twrp.me/zuk/zukz2row.html
- Flash a recent baseband. As a rule, the last one is always the best: https://forum.xda-developers.com/zuk-z2-pro/development/radio-modem-basebands-zuk-z2-pro-t3715835
- Flash a boot.img image with support for early mounting of the system and vendor partitions: https://github.com/cosmedd/android_kernel_zuk_msm8996/releases
- Flash the vendor image for our device (z2_row): https://github.com/zuk-devs/android_vendor_zuk/releases
- Flash the GSI of your choice: https://forum.xda-developers.com/project-treble (Note: ours is an A-only device)
Keep in mind that, as the name implies, generic images will have fewer functions than dedicated ROMs, since they are designed to support as many devices as possible. On the other hand, they are lighter and closer to pure AOSP.
But the basic functions like camera, audio, radio, gps, hardware acceleration, fingerprint, gyroscope, etc... should work out of the box.
If you still do not understand what this means and simplifying a lot... think of boot + baseband + vendor images as the drivers for our device and the Generic System Images (GSI) as the operating system.
In theory, this vendor image will also allows us to get Android 9, 10, 11, etc... with few or no changes.
Now you no longer depend on the developers of Z2 Pro, as anyone from any device can build a GSI. This means more people who can provide an updated system for our device.
Even if you are not going to use GSI now, I still recommend that you download it and keep it in a safe place in case you need it someday.
Thanks to: DD3Boh, davidevinavil and the xiaomi/msm8996 devs, you make life easier for the rest of us!
[VENDOR] Treble support for ZUK Z2 Pro, ROM for the Lenovo Zuk Z2 Pro
Source Code: https://github.com/zuk-devs
ROM OS Version: 8.x Oreo
Last Updated 2018-04-03