First of all, you can add this dependency to your project, without compiling the lib locally.
dependencies {
compile 'com.astuetz:pagerslidingtabstrip:1.0.1'
}
Otherwise if you would like to compile this lib locally, you have to define these keys in gradle.properties in the root.
ANDROID_BUILD_TARGET_SDK_VERSION=19
ANDROID_BUILD_TOOLS_VERSION=19
ANDROID_BUILD_SDK_VERSION=19