自定义布局只有一个EditText：

<EditText
    android:id="@+id/license_value"
    android:inputType="text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="@string/license" />

我正在使用DialogFragment创建对话框.当用户点击ok按钮时,我使用一个界面来获取数据.

public class EditLicenseDialogFragment extends DialogFragment {

    public interface EditLicenseDialogListener {
        public void onDialogPositiveClick(DialogFragment dialog,String value);
    }

    private EditLicenseDialogListener mListener;

    // Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        // Verify that the host activity implements the callback interface
        try {
            // Instantiate the NoticeDialogListener so we can send events to the host
            mListener = (EditLicenseDialogListener) activity;
        } catch (ClassCastException e) {
            // The activity doesn't implement the interface,throw exception
             throw new ClassCastException(activity.toString()
                    + " must implement NoticeDialogListener");
        }
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the Builder class for convenient dialog construction
        AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

        builder.setTitle(R.string.new_license);

        LayoutInflater inflater = getActivity().getLayoutInflater();

        builder.setView(inflater.inflate(R.layout.edit_license,null))

        .setPositiveButton(R.string.ok,new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog,int id) {
                        // GET VALUE. HOW TO DO IT?
                EditText valueView = (EditText) getActivity().findViewById(R.id.license_value);
                if(valueView == null) Log.d("AA","NULL");
                else{
                    String value = valueView.getText().toString();
                    mListener.onDialogPositiveClick(EditLicenseDialogFragment.this,value);
                }
            })
        .setNegativeButton(R.string.cancel,new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog,int id) {
                EditLicenseDialogFragment.this.getDialog().cancel();
            }
        }); 

        return builder.create();

    }
}

在我的活动中,我执行以下操作：

public class LicenseListActivity extends FragmentActivity 
    implements EditLicenseDialogFragment.EditLicenseDialogListener{

    ...

    findViewById(R.id.buttonAddLicense).setOnClickListener(
            new View.OnClickListener() {
                public void onClick(View view) {
                    DialogFragment dialog = new EditLicenseDialogFragment(true);
                    dialog.show(getSupportFragmentManager(),"EditLicenseDialogFragment");
                }
            });

    @Override
    public void onDialogPositiveClick(DialogFragment dialog,String value) {
       Log.d("TAG",value);
    }

我尝试在DialogFragment中检索的EditText始终为NULL.如何获取EditText的值？

谢谢！