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Comment by karthikv | Hacker News Reader

The only thing that sucks (for me) is the app has to be developed using Java. The SDK does not support native application development yet.

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Just curious, why is that a problem? The whole idea behind Android is that handset manufacturers can be free to vary their underlying linux implementations as long as they can adapt their drivers to the Android libraries. Then the programmer can code to this common interface without worrying about differences between handsets. If you were coding directly to the handsets native functionality then you break the cross platform universality. Then its just a repeat of JavaME all over again where you end up with separate builds for different devices.

From what I've read so far, there technically shouldn't be a reason why Ruby (via JRuby) and Python (via Jython) couldnt eventually be used to code Android apps. The SDK compiles Java code to native java byte code, which is in turn compiled to "Dalvik" byte code to be used by the Android VM. How the java byte code is generated (javac, jruby, jython, etc) should not matter, assuming it is using only the supported libraries.

Many of the Android libraries are written in C, so if they had a stable API/ABI then portable native apps could be written. It would be merely expensive.

Do you mean written in Java, or targeted to the JVM?

Apologies if this is a dumb question -- I haven't read this yet.

Yeah, that is a very important distinction.

I meant written in Java. BTW, they have their own VM called Dalvik virtual machine.

There are people trying (I am one of them). It runs off bytecode (which is converts to another format) - so it looks possible. Will find out shortly. I am interested in jruby, jython and scala.

You write it in Java and then it's compiled to their own proprietary virtual machine - Davlik. Rather than Jython, I'd hope for a tool that would turn python straight onto Davlik bytecode.

Hopefully there should be either documentation/source for the VM at some point or an enterprising person is reverse engineering it as we speak.

I don't mind the Java that much, but I would have preferred Python. The one thing that really bothered me was all the XML intertwined and spangled all over...

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