Question

I don’t really know much about the capability of the different OSs. However, I was wondering if I wrote a program in Java using Eclipse on Windows, would I be able to somehow open the program on an Android tablet? Is there something like command prompt on Android where I could execute the Java files?

The program itself doesn’t use any Java API’s, just simply java.util.Scanner.

Answer 1

Well,

Having just written my first game for Android (using the Canvas) and then converting the whole thing to use LibGDX, I will give you an answer based on my experience. And you are exactly correct, I used Eclipse on Windows Vista 64.

Here’s what you are going to want to do…

1. Install the lastest Java SDK.
   Make sure to set your JAVA_HOME variable after installing and also include %JAVA_HOME%\bin in your PATH environment variable. It is installed correctly when you can go to a command prompt and type java -version and get a valid response (something other than Bad command or File Name).

   1. Download and install Eclipse.
      The version you want is Helios (setup for Java development).

2) Download any drivers you need in order to hook up your android phone to the PC (this will depend on the phone you have). If you don’t have an android phone, then this step does not apply to you.

3) Download and install the Android ADK

4) Install the Android ADT eclipse plugin via the main menu:Help:Install New Software option. The URL to use should be https://dl-ssl.google.com/android/eclipse/.

5) If you are going to be developing a game, choose to use LibGDX, which is a free (FREE!!) OpenGL library which will give you all the performance you might want at a fraction of the learning curve (although even then the learning curve can be quite steep at some critical points if only because the documentation is so fragmented and oftentimes vague or incomplete – I am hoping to do a major brain dump of all the steep learning areas in a blog or some other form some day when I have extra time (and you know how often those days come along).

6) If you are going to use LibGDX, you are very happy, because you can write and debug your android application directly under Windows or Mac or Linux and then with less than 10 lines of code, have it also running on the Android.

7) If you are going to develop directly for the Android OS and do not have an actual android device, then you will need to set up an emulator. The emulator comes with the ADK, you will use it to configure an instance of a virtual android device – Do a google search on how to do that. That being said, this option is very, very slow if you are going to do the normal code, test, debug, code, test, debug cycle. You really need an actual android phone or tablet for this to be even partially acceptable performance wise.

And finally, in answer to your actual question, yes, you can run and debug your android application directly from within Eclipse. You can set breakpoints and single step through your code on an actual android device or on a software emulated android device (or if using LibGDX, on your windows box directly). And I yes, java.util.Scanner is available in Android, but you will probably find it to slow (and if you are reading vertices, you probably want to use LibGDX which will probably already have a class that does what you are wanting to do – really!).

I hope that helps – If it isn’t enough to get you going, you might want to consider a different hobby, because with Android development, it generally will stay pretty complex all the time (and the tools are definitely not bug-free themselves as you will find).

Backup often and have fun! Good Luck!!

rpbarbati