Develop Reference

Setting up Android environment in Eclipse

While creating Android environment in eclipse, I receive this error:
Folder can't be moved because it's open in another folder
, and when updating, it all fails as Eclipse doesn't find the SDK location, because emaluator.exe file is no longer existing as part of the tools of the SDK. I have preinstalled system-image, etc. Any ideas on how to fix this issue without re-installation?

As a beginner and as now Google has their own IDE for developing Android App, you better should start your development journey with Android Studio. It is powerful, beautiful and very easy to use. Why you are using Eclipse still now? If you use Eclipse, you have to install Android SDK, Android Emulator. And you are getting all the tools in one place with Android Studio.
Moreover, Android Studio has IntelliJ engine inside. It is known as the best java ide. Super auto code completion, intelligent code inspector and so on.

Android Studio has become the way to go for Android developers now-a-days. It is easier to use because is based on the IntelliJ Idea which is per se a much better java programming environment than eclipse, it predicts way better what you may need to write, and google has made it so that you have all your interface, simulator and code all in the same environment. On top of that google won't update the Android SDK to work with Eclipse anymore!

Do I have to download Android Studio if I am already using IntelliJ IDEA?

I am already using IntelliJ IDEA. Do I have to download all the Android Studio files (almost 1 GB)?
Can't I just download the SDK and continue on developing?

Yes, you can download only the SDK. You can find the download link here, under "SDK Tools Only".

My understanding is this: IntelliJ IDEA's Android plugin does not always have all the latest Android-specific features, developed by Google, that are already in Android Studio.
IDEA is fine too, but if you seriously do Android, just get Android Studio, you'll be better off with it.
(I use—and love—IntelliJ IDEA too for backend & web development. Having both installed is no problem. Who cares about 1 GB of disk space.)

Sharing a common Android SDK on both Android Studio and Eclipse

I am on Windows 8. I have some questions regarding Android SDK:
Can both IDEs share a common Android SDK?
Will there be any issues in updating IDEs?

Generally, yes, it's safe to share a common Android SDK for both Eclipse and Android Studio. Updating IDEs won't affect the SDK at all.
Take note when updating/deleting packages in Android SDK Manager: you might use some packages (e.g. specific API version) in a particular IDE (past example: Android "L" Developer Preview in Android Studio). Updating/deleting them may break the project that use them, and it might be difficult to fix the issue. However, for already-stable APIs like Android KitKat (API 19) and below, there won't be any issue when updating them.
Additional note: Android project created in either Android Studio or Eclipse is not really compatible to each other due to different project structure and technology. Therefor, it's better to always use the same IDE for projects that are created in it. If you want to test both IDEs on same project, it's better to export the project from Eclipse, instead of from Android Studio as it's easier.

Using IntelliJ with Android plugin, rather than using Android Studio

I wonder if there is any difference between using the Android Studio, Google offer to use, and use the IntelliJ Base IDE, and install the Android plugin?
Would it effect the project and module handling?
Would it effect facets?

I've been using IntelliJ IDEA 12 for Android projects for a long time. Android studio has a lot of beneficial additional Android integration, such as:
Inline Lint API checks
Drawable and string previews
Better layout editor
Built in Gradle support
Better DDMS integration
But you can certainly just use the community edition of IntelliJ 12 for Android projects, and for production projects, I would say it's preferable at this time until Android Studio stabilizes. Also, I believe IntelliJ 13 will essentially include all of the Android functionality that Android Studio does, from what I've heard.

This is useful FAQs about Android Studio vs Android Plugin in IntelliJ IDEA.
It is clear to me that
The EAP (Early Access Preview) of IntelliJ IDEA 13, which includes all of the Android Studio features except for the redesigned new project wizard and the App Engine cloud endpoints integration, is available now.
http://blog.jetbrains.com/idea/2013/05/intellij-idea-and-android-studio-faq/

As of today, Android studio actually functions, so I guess this would be my immediate solution. plus I'm not even sure the Android plugin would support all the features as Android studio will, and that there would not be any conflicts... better safe then sorry.

New to android dev

I am new to android dev, own an HTC Eris Droid (OS = 1.5 or 1.6 I believe). I am primarily a Microsoft .NET developer and am trying to figure out where to start.
What dev IDEs are suggested. I've seen the droid dev site and they suggest Eclipse. But which one?
Will installing Eclipse and the JRE interfere with .NET development?
What else will I need to get started? My OS is Win7.
TIA

As a .NET developer who has recently been looking at Android development, I can give you the steps I used:
Download Eclipse Classic 32-bit (as recommend by the Android docs) and extract it to a folder where it has write permissions (I use %homepath%\applications\eclipse\3.5\)
Download and extract the Android SDK to a permanent home and run SDK Setup.exe. Let it download/install all the packages
Add ANDROID_SDK_HOME\tools (expanded, obviously) to your %PATH% system environment variable in System Properties (WIN+BREAK)
Install the ADT (Android/Eclipse integration) plugin for Eclipse
Then to checkout the samples:
Create a workspace and a new Android project
Copy the contents of one of the samples (ANDROID_SDK_HOME\platforms\android-x.x\samples) into your project directory
Refresh your Eclipse view
I also strongly recommend checking out the Android Developer Guide and, in particular, reading the Application Fundamentals. It really gives a good overview of the terms used and the lifecycle of an application.
After that you can dive into the samples (installed by the SDK) with a little bit of clarity.

For development you will need*:
Java JDK - the JRE is not enough for Java development.
Eclipse - it doesn't really matter which "package" you choose, but for your needs the basic (smallest) one should be enough.
Android SDK + ADT
This should have no effect on .Net development, or on anything for that matter.
You don't actually need Eclipse and ADT, but since you asked about IDEs...

The android developer site system requirements says any version of Eclipse after 3.3.
Eclipse uses plugins to support different configurations that's why www.eclipse.org/downloads/ has so many different versions - they're the core IDE with different plugin configurations.
I'd recommend the 'Eclipse IDE for Java Developers' as this will have what you need without too many bits you don't - you can install additional plugins easily.
Of course, you'll also need to add the Android SDK once you have Eclipse - this is a set of tools and plugins that work with Eclipse.
Installing Eclipse and the JRE (Although you want the JDK - The Development Kit rather than just the runtime) will not interfere with your .Net development.

This version of Eclipse should work fine. Just select a download mirror.
You probably already have the JRE installed, but you should install the JDK from here.
Then you need to get the Android SDK, and ADT

After you install the Android SDK, it may be useful to create multiple virtual devices using the included Android emulator running different versions of Android. This will help you to learn features included in Android up to version 2.1 instead of being limited to your current device running 1.x.