getCheckedRadioButtonId() returning useless int?

getCheckedRadioButtonId() returns the id of the RadioButton(or -1 if no RadioButtons are checked) that is checked in the Radiogroup. If you set distinct ids to the RadioButons in the layout then you will try to match those ids with the return of the method to see which one is checked:

//field in the class
private static final int RB1_ID = 1000;//first radio button id
private static final int RB2_ID = 1001;//second radio button id
private static final int RB3_ID = 1002;//third radio button id

//create the RadioButton
RadioButton rb1 = new RadioButton(this);
//set an id
rb1.setId(RB1_ID);


    int btn = radioGroup.getCheckedRadioButtonId();
    switch (btn) {
    case RB1_ID:
        // the first RadioButton is checked.
    break;
        //other checks for the other RadioButtons ids from the RadioGroup
    case -1:
        // no RadioButton is checked inthe Radiogroup
    break;
    }

store the checked ID, then compare it to each button using the function radioButton.getID() using a switch statement or if-else chains