android studio switch between multiple sdk version

Question

If I install multiple SDK version, how can I switch it between it to use new API or old API?

eg My android list target output as below:

Available Android targets:
----------
id: 1 or "android-19"
     Name: Android 4.4.2
     Type: Platform
     API level: 19
     Revision: 2
     Skins: HVGA, QVGA, WQVGA400, WQVGA432, WSVGA, WVGA800 (default), WVGA854, WXGA720, WXGA800, WXGA800-7in
 Tag/ABIs : default/armeabi-v7a
----------
id: 2 or "android-L"
     Name: Android L (Preview)
     Type: Platform
     API level: L
     Revision: 3
     Skins: HVGA, QVGA, WQVGA400, WQVGA432, WSVGA, WVGA800 (default), WVGA854, WXGA720, WXGA800, WXGA800-7in
 Tag/ABIs : no ABIs.

But when I try to create a L android application, it seems I still no see the new API for L.

Answer 1

I you want to target other versions, then you must install different "System Images"

Then when you wish to create an AVD under "Target" there will be an extra option to target those versions.

This is only for AVDs(Virtual Devices) if you wish to code for older versions you will need to use support libraries

Answer 2

don't use the Android L preview .. you will get some bugs

just use either Android 4.4W API20 or Android 4.4.2 API 19

if you can't see one of both I suggest you to install a new version of android SDK Manger