Android Activity: how to init variable with constructor? Do I need putExtra?

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http://stackoverflow.com – I have public abstract class SuperClassA extends Activity { protected String s; public SuperClassA(String s) { this.s = s } ...etc... } Now I do startActivity(new Intent(this, SubClassA.class)); Is there some way to call the activity while using the constructor? Otherwise the field s is not initialized. Or do I really have to do this with putExtra? (HowTos)