RadioGroup finding selected id

Question

private static final String TAG = MainActivity.class.getSimpleName();
EditText etName;
EditText etAge;
Button bPredict;
RadioGroup rdGroup;
Boolean maleOrFemale;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    getSupportActionBar().hide();

    bPredict = (Button)findViewById(R.id.b_predict);
    etName = (EditText)findViewById(R.id.et_name);
    etAge = (EditText)findViewById(R.id.et_age);

    bPredict.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            String name = etName.getText().toString();
            String age = etAge.getText().toString();
            maleOrFemale = false;
            maleOrFemale = radioGroup();
            predictIntent(name, age, maleOrFemale);
        }
    });
}

public void predictIntent(String name, String num, Boolean maleOrFemale){
    Intent toPredictActivity = new Intent(this, predict.class);
    toPredictActivity.putExtra("name", name);
    toPredictActivity.putExtra("age", num);
    toPredictActivity.putExtra("maleOrFemale", maleOrFemale);
    startActivity(toPredictActivity);
}

public boolean radioGroup(){
    Boolean maleOrFemale = true;
    int selectedId = rdGroup.getCheckedRadioButtonId();

    if (selectedId == R.id.rd_male) {
       return false;
    }else{
        return true;
    }
}

}

ERROR java.lang.NullPointerException: Attempt to invoke virtual method 'int android.widget.RadioGroup.getCheckedRadioButtonId()' on a null object reference

This error is output and not sure why and would just like some help resolving this issue. Thanks in advance

So the problem is "rdGroup" is null. Put your onCreate code in the question. — yshahak, Jul 12 '15 at 10:10

score 0 · Answer 1 · answered Jul 12 '15 at 10:17

0

public boolean getSelectedGender()
{
    int checkedId = rgGender.getCheckedRadioButtonId();
    if(checkedId == R.id.rbMale) {
        return true;    // male
    }
    else {
        return false;   // female
    }
}

answered Jul 12 '15 at 10:17

Piyush Malaviya

1,091
13
17

score 0 · Accepted Answer · answered Jul 12 '15 at 10:29

You not initializing it. you need to add this to onCreate:

@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_main);

   getSupportActionBar().hide();

   rdGroup = (RadioGroup)findViewById(R.id.the_id_as_define_in_xml);

   bPredict = (Button)findViewById(R.id.b_predict);
   etName = (EditText)findViewById(R.id.et_name);
   etAge = (EditText)findViewById(R.id.et_age);
}
//rest of code

score 0 · Answer 3 · answered Jul 12 '15 at 10:32

1st, your RadioGroup is never initialized, 2nd, you locally redefine your class variable but never use it Boolean maleOrFemale = true;, so I guess you have to change it to maleOrFemale = true; and 3rd, the whole method can be reduced to

 public boolean radioGroup(){
   return rdGroup.getCheckedRadioButtonId() == R.id.rd_male;
 }

RadioGroup finding selected id

3 Answers3