Trouble installing Android 4.2 APIs

I updated ADT through Eclipse today to version 21. Now when I open the SDK Manager I would expect there to be a folder like "Android 4.2 (API 17)", which would contain the SDK Platform and APIs, documentation, etc. However, instead I just get a folder called "API 17", and the only thing in it is "Google APIs", which I can't even install because

> Installing this package also requires installing: > - Missing SDK Platform Android, API 17

What do I do here? Thanks

I figured this out myself after some poking around. I went into the settings for the SDK Manager, cleared the cache, and told it to use HTTPS, then refreshed the listing and it all appeared normally.

Eclipse > Window > Android SDK Manager > Packages > Reload

It then properly updated the UI to let me choose updated software.

Why do I need to click "Reload" manually ?! I expect that to happen automatically when I open the SDK Manager.

By this step~

Eclipse > Window > Android SDK Manager > Packages > Reload

then install the sdk

ref: http://my.eoe.cn/iceskysl/archive/1027.html

Eclipse > Window > Android SDK Manager > Preferences > Clear Cache Button click> Done.

I had this problem in ubuntu.

• Open a terminal and navigate to the android-sdk-linux folder: cd android-sdk-linux

• Then manually update the sdk: tools/android update sdk -u

After it is done, restart Eclipse.

As error suggest : API 18 depends on SDK version n etc etc. So first update SDK tool to latest version (deselect API 18) then try to install API 18.

Try approving each package one by by instead of doing approve all. If any package has an error, you can't download all at the same time.