开始为 Android 开发，我应该选择安装哪些 SDK？

Question

I'm starting to broad my developer skills also to the Android development.

I installed all the tools and configurations and every thing seem great, As a default settings I install the 3.2 SDK, but there is not too much docs on that one, mode of what is out there is on the 2.x SDKs.

Is it like IOS, does android have a good backward computability? Can I stay with the 3.x and count on it (with the features that are in the 2.x SDKs) to work on 2.x phones? What are the common version in the Android devices this days? I have lots of newbie develop questions like that, as i want to start from a good starting point and there are lots of materials and tutorials over the web that are not up to date.

Also, does any one know about a good site for this kind of Q&A?

Thank you, Erez

Answer 1

As of July 5th the version with the largest market share (59.4%) is 2.2 (API Level 8) as shown here http://developer.android.com/resources/dashboard/platform-versions.html so Consequently I would recommend using that as a starting point unless you are solely focusing on the new honeycomb tablets (<1% market share).

As for backward compatibility, android is completely backward compatible for the most part. Unless of course you use a new feature that is only available starting with a certain API level. Google's Android market is good about only allowing apps that will run on a certain API being visible to that phones user. This is enforced by the API level as recorded in the manifest file that is created with every Android app and set by the developer.

To help you with the API level, the SDK docs show what API a feature/object started with in the upper left hand corner. You can also view the specific changes in each platform and it's corresponding API level at http://developer.android.com/sdk/index.html .

As for a good website to get started I would recommend the developer site at developer.android.com and this website of course. Also the book Android Wireless Application Development by Shane Conder and Lauren Darcey (2 ed) Is very good. (I am not connected with the book just currently reading it). Make sure you get the latest edition.

Hope this helps, George

Answer 2

Above is good info, but it would be advisable to develop for 2.1 and up at the moment, considering as of this answer's writing, 2.1 makes up 17.5% of the market and 2.2 makes up 59.4% of the market.

http://developer.android.com/resources/dashboard/platform-versions.html

OP should also be advised that version 3.x is specifically for tablets, so that may not be the best choice for a starting developer. My advice is to go with 2.1. Most of the documentation is up to date with that, and you won't have access to things you don't need yet (fragments, tablet-specific things)

Hope this helps!

Answer 3

You can read about application forward and backward compatibility in the docs.

Generally apps are forwards compatible but not backward compatible - new APIs introduced in one version are not available in an older version.

This pie chart shows distribution of devices accessing the Android Market and based on this I would try to target devices using 2.1 or newer to cover most of your users.

Your decision should be based on whether you need a feature introduced in a specific version. For example, if you want to add NFC to your app, you'll need Android 2.3.3 or newer, but otherwise there's no reason to exclude older devices.

I recommend learning about Fragments and using the compatibility package to use them on targets below 3.0. This will make it easier to reuse view elements on both tablet and phone devices. Note that if you only intend to develop for phones, 2.3.4 is the latest phone version of Android at the time of writing. Later this year, 3.0 for tablets will merge with the phone version to provide a unified OS version as with iOS.

Answer 4

Android 3.2 is just released publicly on friday, July 15th. You can start-off with Android 2.3.3 and 3.2 installation and development.

Android applications are mostly forward compatible. (But not always) The best place to find all your answers is developer.android.com