Creating object using a form, adding it to a list on another activity

Question

I want to retrieve a value from a text of a radiobutton inside a radiogroup. This sounds really simple but I am not being able to put it to work as it always gives me a null value.

Here is my code:

public class NewMovie extends FragmentActivity {    
RadioGroup rating;
RadioButton selectedRating;
int selectedRatingIndex;

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.new_movie_layout);
        rating = (RadioGroup) findViewById(R.id.rating);
        onClickListenerButton();
}

public void onClickListenerButton()
{
    selectedRatingIndex = rating.getCheckedRadioButtonId();
    final RadioButton selectedRating = (RadioButton) findViewById(selectedRatingIndex);
    intent.putExtra("rating", selectedRating.getText().toString());
    setResult(RESULT_OK, intent);
    finish();
}
}

XML:

        <RadioButton
            android:id="@+id/U"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/U" />

        <RadioButton
            android:id="@+id/PG"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/PG" />

        <RadioButton
            android:id="@+id/r12"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/r12" />

        <RadioButton
            android:id="@+id/r15"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/r15" />

        <RadioButton
            android:id="@+id/r18"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/r18" />
    </RadioGroup>

Always nullpointerexception for some reason.

Don't know if it helps the context, but I am trying to go from activity 1 to activity 2, in activity 2 (the one I show above) display the radiogroup and the user then submits one of the answers and the answer is then used in activity 1.

Answer 1

You have to put a default select in radio buttons, Try as follow,

1. Place all your radio buttons with in radio group in xml

   <RadioGroup
       android:layout_width="wrap_content"
       android:layout_height="wrap_content" >
   
         <RadioButton
           android:id="@+id/U"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:text="@string/U"
           android:checked="true" />  // deafult select
   
           //other radio buttons  
   </RadioGroup>
   

2. Initiate all radio buttons in activity

   radioU=(RadioButton) findViewById(R.id.U);
   

3. Check the selection in button click event

   public void onClickListenerButton(View v) {
   
   if(radioU.isChecked())
   {
       intent.putExtra("rating", getResources().getString(R.string.U));    
   }
   else if(radioPG.isChecked())
   {
       intent.putExtra("rating", getResources().getString(R.string.PG));   
   }
   
   setResult(RESULT_OK, intent);
   finish();
   }