getAllTests and getTestSuite in android.test.InstrumentationTestRunner

Question

I've created a test runner extending android.test.InstrumentationTestRunner. I'm looking for a way to define the set of tests to get executed based on a set of configurations.

I thought I may be able to override the below methods to return my custom test suite, however, these are not getting called! Just wondering whats the use of these:

public TestSuite getAllTests () public TestSuite getTestSuite ()

Any clues? Any other alternatives I can use to define a custom test suite at runtime?

Thanx