Android-HTTP GET请求

Question

I am trying to make an android app which can send a GET request to a server on a local network. I have found an example here , and used the GET example. I changed the getURL string to be the address I want to send to (192.168.1.177/?testGET). I then attached the function to a buttons onClick event, but when I test the app on my phone, the app closes as soon as I press the button. See below for the code.

public void sendGETrequest(){
    try {
        HttpClient client = new DefaultHttpClient();  
        String getURL = "192.168.1.177/?testGET" ;
        HttpGet get = new HttpGet(getURL);
        HttpResponse responseGet = client.execute(get);  
        HttpEntity resEntityGet = responseGet.getEntity();  
        if (resEntityGet != null) {  
                    //do something with the response
                    Log.i("GET RESPONSE",EntityUtils.toString(resEntityGet));
                }
} catch (Exception e) {
    e.printStackTrace();
}
}

Why might this not be working? Also is there a way to dynamically add parameters to the end of the URL to be read by the server.
See below for the output of the console window
[2014-01-19 15:44:25 - sensorTest] ------------------------------
[2014-01-19 15:44:25 - sensorTest] Android Launch!
[2014-01-19 15:44:25 - sensorTest] adb is running normally.
[2014-01-19 15:44:25 - sensorTest] Performing com.example.sensortest.MainActivity activity launch
[2014-01-19 15:44:51 - sensorTest] Uploading sensorTest.apk onto device 'P772N10_VIRGIN'
[2014-01-19 15:44:51 - sensorTest] Installing sensorTest.apk...
[2014-01-19 15:44:58 - sensorTest] Success!
[2014-01-19 15:44:58 - sensorTest] Starting activity com.example.sensortest.MainActivity on device P772N10_VIRGIN

When I open the app and press the button, it closes with the message "Unfortunately, sensor test has stopped."

Answer 1

Without a logcat, it's hard to say what is causing the crash. But I'm quite certain that it's because you are doing networking on the main thread.

See NetworkingOnMainThreadException

It doesn't necessarily explain much, but basically, you can't do network (or long running) tasks on your main thread as it potentially hangs the UI. This is probably a better explanation though.

As for 'dynamically adding parameters', you could just change it to something like this:

public void sendGETRequest(String paramaters){
    ...

    String getURL = "192.168.1.177/?testGET&" + paramaters;

    ...
}

and you can pass parameters with the method call like so:

sendGETRequest("username=admin&password=123Password321!");