Android :: Eclipse Content Assist Not Working With Android

I'm not sure is this is a problem with my installation of Eclipse (Helios) and Android SDK or something else but Eclipse Content Assist doesn't propose Object Methods for Android classes. For example, if I create a simple program and add a Button btn, when I go to use the btn method setBackgroundResource(int) with Content Assist (Ctrl + Space) or Word Completion (Alt + /) neither of them have any proposals. If I type btn.(Ctrl + Space), Content Assist lists; equals(), getClass(), hasCode(), Notify() wait(), shows none of the Button methods!

import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
public class HelloWorld extends Activity {
@Override public void onCreate(Bundle icicle) { super.onCreate(icicle);
setContentView(R.layout.main);
Button btn = Button(this);
btn.(Ctrl + Space) } }