Question: I'm using eneter framework to process communication in my android application;
the problem is when **I'm trying to populate a spinner, setting the adapter to the spinner cause an undefined exception**

Here the code

```
public void populateSpinner(TypedResponseReceivedEventArgs<String> arg1){
    List<String> list = new ArrayList<String>();
    String listf = arg1.getResponseMessage();
    //sendToDebug(listf);
    StringTokenizer tokenizer = new StringTokenizer(listf,",");
    while(tokenizer.hasMoreElements()){
        list.add((String)tokenizer.nextElement());
    }
    //EditText text = (EditText)findViewById(R.id.number2EditText);
    //text.setText(list.size());
    //text.setText(listf);
    Spinner forfait = (Spinner)findViewById(R.id.forfaitsSpinner);
            ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,list);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    forfait.setAdapter(adapter);
}

```

Answer: 
you are passing `this` in the following piece of code,

```
 ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                    android.R.layout.simple_spinner_item,list);

```

Not sure in which block this code lies or which class, but ensure that **`this`** refers to `ActivityName.class` or `the context`
It is most likely because you are using an `ArrayAdapter` rather than a `SpinnerAdapter`. `ArrayAdapter` is an indirect implementer of the `SpinnerAdapter` interface rather than one which declares that it implements the interface. Check the undefined exception. It is likely telling you that `setAdapter(ArrayAdapter)` is not defined for `Spinner`.