How do i make a button execute this method

Question

This may be a super easy answer but my app crashes when I push the button. This is the method im trying to run the the click of a button:

public void postData() {
    // Create a new HttpClient and Post Header
    HttpClient httpclient = new DefaultHttpClient();
    HttpPost httppost = new HttpPost("http://www.yoursite.com/script.php");

    try {
        // Add your data
        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
        nameValuePairs.add(new BasicNameValuePair("id", "12345"));
        nameValuePairs.add(new BasicNameValuePair("stringdata", "AndDev is Cool!"));
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

        // Execute HTTP Post Request
        HttpResponse response = httpclient.execute(httppost);

    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
    } catch (IOException e) {
        // TODO Auto-generated catch block
    }
}

I made sure I have :

 <uses-permission android:name="android.permission.INTERNET"></uses-permission>

and here is my activity main:

 <Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_below="@+id/textView1"
    android:layout_marginTop="16dp"
    android:onClick="postData"
    android:text="Button" />

score 3 · Accepted Answer · answered Jun 30 '13 at 16:24

3

The signature of the method should be

public void postData(View v)

Another thing, You can not perform network operation in main UI thread. Use AsyncTask instead

answered Jun 30 '13 at 16:24

stinepike

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1

Eh. Beat me by ten seconds :P +1 – Raghav Sood Jun 30 '13 at 16:25
@RaghavSood at the same time.. why you deleted that, pointed when upvoting yours – stinepike Jun 30 '13 at 16:26
I missed out on the UI Thread networking issue. Your answer already had that information. Didn't make sense to duplicate it :P – Raghav Sood Jun 30 '13 at 16:26
Im not sure I understand how to use the Async Task, can you explain? – BluGeni Jun 30 '13 at 16:28
@BluGeni , go to the link I have posted, There is a nice example :) – stinepike Jun 30 '13 at 16:29

score 0 · Answer 2 · edited May 23 '17 at 10:32

0

The application may be crashing because connecting to internet is not allowed on UI Thread. So, you should AsyncTask to post data to HTTP Web Services.

More details can be found in this discussion (How to fix android.os.NetworkOnMainThreadException?)

edited May 23 '17 at 10:32

Community

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1

answered Jun 30 '13 at 16:25

Wand Maker

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Raghunandan · Answer 3 · 2013-06-30T16:38:45.703

You should use a asynctask for network related opearation or create a new thread.

  HttpResponse response = httpclient.execute(httppost);

If not you will NetWorkOnMainThreadException.

On button click

        new PostData().execute();

Then

      class PostData extends AsyncTask<Void,Void,Void>
      {
              @Override
              protected void doInBackground(Void... params)
              {
                    HttpClient httpclient = new DefaultHttpClient();
                    HttpPost httppost = new HttpPost("http://www.yoursite.com/script.php");

                    try {
                        // Add your data
                       List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
                       nameValuePairs.add(new BasicNameValuePair("id", "12345"));
                       nameValuePairs.add(new BasicNameValuePair("stringdata", "AndDev is Cool!"));
                       httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                       // Execute HTTP Post Request
                       HttpResponse response = httpclient.execute(httppost);

                       } catch (ClientProtocolException e) {
                       // TODO Auto-generated catch block
                       } catch (IOException e) {
                       // TODO Auto-generated catch block
                       }
                       return null;           
              }   
      }

For more info check the docs

http://developer.android.com/reference/android/os/AsyncTask.html

How do i make a button execute this method

3 Answers3