Android prompt dialog using alert builder

PromptDialog.java

final EditText txt = new EditText(this);
new AlertDialog.Builder(this)
   .setTitle("Title")
   .setView(txt)
   .setPositiveButton("Ok", new DialogInterface.OnClickListener() {
     public void onClick(DialogInterface dialog, int whichButton) {
       String url = txtUrl.getText().toString();
       //do smth. with it.
     }
   })
   .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
     public void onClick(DialogInterface dialog, int whichButton) {
       dialog.cancel();
     }
   })
   .show();