Native-Android-discussion

native Android

There are a lot of rumors and statements around regarding OEM mainly (only?) supporting Android for there chipsets now/in the future.
There is an idea in the room regarding how we can leverage that without having to have Java/Dalvik.

The idea is to remove at least the Dalvik layer, maybe everything but the kernel.

Thomas Senyk’s thoughts on that:

So two questions at hand are:

• “Could we do a “android-BSP without DalvikVM”-setup and have Qt running on this?”
• “Would this reduce the amount of work when porting to an new board?”

What we need/want:

• multi-process including opengl-painting
• multimedia playback; using QtMultimediaKit if possible

We have some pros and cons if we use android-BSPs:

PROS:

1. Standardized media-playback (OpenMAX AL) from android-14 (4.0) and forward.
   There is already a OpenMAX_AL-QtMultimediaKit implementation for symbian (could serve as a base/start for a linux/android implementation)
2. Very good OpenGL+EGL implementations
   … but: see “No multi-process” in cons

CONS:

1. There might be some legal/politic issues. (As with ANY other android approach!). Nokias should check with legal.
2. officially ARM only (x86 also, but x86 is not a problem-child anyway)
3. No multi-process
   1. You can’t use SurfaceFlinger (that easy) because it’s started and managed by “System Server” which is a Dalvik-process!
      Or in other words: SurfaceFlinger does only come with the full android-stack.
   2. The basic kernel-enables (e.g. PMEM, CMA) are only the first step towards a linux multi-process solution (e.g. wayland), the real work starts after that.
   3. What’s left is basically: single-process EGLFS (backed-up by very good OpenGL+EGL implementations)
      … that was never a big problem on any device I worked on!
4. A lot of non-standard implementations of various OS-utilities. (ashm (instead of posix shm), binder (instead of dbus), …)
5. It’s all just a big hack where you (Qt) would stand in the middle of things. It’s not really android and it’s definitely(!!) not real linux!
6. You will need a lot of special solutions for special problems. You have to maintain those!

This means: you are building yet another setup/platform in which nobody is interested in.
If you want to give Chipset-Vendors a recommendation: They should use the work they’ve invested in android (kernel, EGL, OpenGL, OpenMAX,…) and build (as a their second offering) a proper REAL linux instead of playing around and doing something which has no name and no future!
If you want to give Produkt-developers a recommendation: Either insist on a proper REAL linux BSP … OR use the full android stack (e.g. via necessitas)

Android with dalvik. Qt without Java

“Can we do a Qt port on a full android-stack, but only using the android-ndk and no Java?”
This would mean that everything is started and managed in the usual way (full android-stack!!!), including a lot of Dalvik-processes.
But Qt(-Applications) would only use the android-ndk.
Performance and foot-print vice this will be something between android-BSP-without-Dalvik and necessitas.

I don’t see much PROs against necessitas! (but a lot CONs!!)