Not able to use new resource identifiers in Android with targetSdkVersion defined in manifest

I'm developing an Android application that I'd like to be compatible with 1.5 (SDK version 4). I'm testing the application on 2.2 (SDK version 8). To do this, I'm including in the manifest file the line

<uses-sdk android:minSdkVersion="4" android:targetSdkVersion="8" />

I thought this would allow me to use the newest manifest elements and APIs, but I'm getting a compile error whenever I try to use them. For example, I try to define the element installLocation to allow the app to be installed on the SD card, but Eclipse gives me the error

No resource identifier found for attribute 'installLocation' in package 'android'

Is there something else I have to do to get this to work? If I can't get this to work, what bene开发者_Python百科fit is defining targetSdkVersion?

Make sure that you are using building against the android 2.2 jars. Right click on your Eclipse project, choose, properties, go down to Android and make sure the correct sdk is selected.

Change the build target by editing the project properties in Eclipse, and choose a target with at least API Level 8: ("I'm testing the application on 2.2 (SDK version 8)").