Well, I found a solution that worked for me, because I had very few RadioButtons.
OnClickListener() RadioButton .
final RadioButton a1 = (RadioButton) findViewById(R.id.a1);
final RadioButton a2 = (RadioButton) findViewById(R.id.a2);
a1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
a2.setChecked(false);
}
});
a2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
a1.setChecked(false);
}
});