indexof error html page

I have an error when i'm going to do this operation:

if(file.i开发者_JS百科ndexOf("message") > 0)
   txtview.setText(file.indexOf("message"));

Where is the problem? The var file contains the html source of a web page.

try this code

txtview.setText(""+file.indexOf("message"));

you pass the integer value while this method require string