How to read a text file from url in android

Question

I wanna to write an app that need to recive some text from server this is my code :

String db = ""
new Thread(new Runnable() {
            @Override
            public void run() {

                try {
                    // Create a URL for the desired page
                    URL url = new URL("http://chemvaaj.xzn.ir/test/words.txt");

                    // Read all the text returned by the server
                    BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
                    String str;
                    while ((str = in.readLine()) != null) {
                        // str is one line of text; readLine() strips the newline character(s)
                        db+=str;
                    }
                    in.close();
                } catch (MalformedURLException e) {
                } catch (IOException e) {
                }

            }
        }).start();

        searchEditText.setText(dbd);

it seems right but the variable db is stil "" in the end .

"But it doesn't work". Seriously? 400+ rep and the error we get is " it doesn't work "? — Luke Joshua Park, Oct 23 '15 at 10:28
There is no runtime or compile error ! its a logical error ! the variable db is empty in the end ! and I dont know how to fix it — Erfan Bagheri, Oct 23 '15 at 10:30
what is this "dbdbd" variable? Did you add internet permission? — Android Android, Oct 23 '15 at 10:31
Well if `db` is empty it likely means your while loop is never executed, which means that there's likely no content to be read from the stream. Start there. — Luke Joshua Park, Oct 23 '15 at 10:34
is it *really* empty? You run an operation in background but try to set the text immediately after the Thread is started — Droidman, Oct 23 '15 at 10:34
You should place `Log` calls in your `catch` statements so you know whether any errors are occuring. — PPartisan, Oct 23 '15 at 10:35
seems like you do not understand basics of multithreading ... http://ideone.com/PPHi95 ... as you can see output is 1-3-2 not 1-2-3 ... you have the same situation — Selvin, Oct 23 '15 at 10:57

score 2 · Answer 1 · edited May 23 '17 at 11:44

Try below code:

Hope that will solve your problem.

Note : Firstly you must do networking operation in another thread because networking in main thread makes your application unresponsive for duration of any request. So put this code in AsyncTask.

DefaultHttpClient  httpclient = new DefaultHttpClient();

HttpGet httppost = new HttpGet("http://chemvaaj.xzn.ir/test/words.txt");
HttpResponse response = httpclient.execute(httppost);
        HttpEntity ht = response.getEntity();

        BufferedHttpEntity buf = new BufferedHttpEntity(ht);

        InputStream is = buf.getContent();


        BufferedReader r = new BufferedReader(new InputStreamReader(is));

        StringBuilder text = new StringBuilder();
        String data;
        while ((data= r.readLine()) != null) {
            text .append(line + "\n");
        }

        searchEditText.setText(text );

Try some other file and test. You will get to know what is the exact problem. — KishuDroid, Oct 24 '15 at 05:52

How to read a text file from url in android

1 Answers1