public class Login extends Activity implements OnClickListener {
private EditText user, pass;
private Button mSubmit, mRegister;
// Progress Dialog
private ProgressDialog pDialog;
// JSON parser class
JSONParser jsonParser = new JSONParser();
// php login script location:
// localhost :
// testing on your device
// put your local ip instead, on windows, run CMD > ipconfig
// or in mac's terminal type ifconfig and look for the ip under en0 or en1
// private static final String LOGIN_URL =
// "http://xxx.xxx.x.x:1234/webservice/login.php";
private static final String LOGIN_URL = "http://192.168.2.4/mybringbacktutorial/login.php";
// testing on Emulator:
//private static final String LOGIN_URL = "http://10.0.2.2:1234/webservice/login.php";
// testing from a real server:
// private static final String LOGIN_URL =
// "http://www.mybringback.com/webservice/login.php";
// JSON element ids from repsonse of php script:
private static final String TAG_SUCCESS = "success";
private static final String TAG_MESSAGE = "message";
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.login);
// setup input fields
user = (EditText) findViewById(R.id.username);
pass = (EditText) findViewById(R.id.password);
// setup buttons
mSubmit = (Button) findViewById(R.id.login);
mRegister = (Button) findViewById(R.id.register);
// register listeners
mSubmit.setOnClickListener(this);
mRegister.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.login:
new AttemptLogin().execute();
break;
case R.id.register:
Intent i = new Intent(this, Register.class);
startActivity(i);
break;
default:
break;
}
}
class AttemptLogin extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Login.this);
pDialog.setMessage("Attempting login...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected String doInBackground(String... args) {
// TODO Auto-generated method stub
// Check for success tag
int success;
String username = user.getText().toString();
String password = pass.getText().toString();
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("username", username));
params.add(new BasicNameValuePair("password", password));
Log.d("request!", "starting");
// getting product details by making HTTP request
JSONObject json = jsonParser.makeHttpRequest(LOGIN_URL, "POST", params);
// check your log for json response
Log.d("Login attempt", json.toString());
// json success tag
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
Log.d("Login Successful!", json.toString());
// save user data
SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(Login.this);
Editor edit = sp.edit();
edit.putString("username", username);
edit.commit();
Intent i = new Intent(Login.this, ReadComments.class);
//finish();
startActivity(i);
return json.getString(TAG_MESSAGE);
} else {
Log.d("Login Failure!", json.getString(TAG_MESSAGE));
return json.getString(TAG_MESSAGE);
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(String file_url) {
// dismiss the dialog once product deleted
pDialog.dismiss();
if (file_url != null) {
Toast.makeText(Login.this, file_url, Toast.LENGTH_LONG).show();
}
}
}
}
---- --- logcat中
11-12 13:05:16.982: E/AndroidRuntime(28094): FATAL EXCEPTION: AsyncTask #1
11-12 13:05:16.982: E/AndroidRuntime(28094): java.lang.RuntimeException: An error occured while executing doInBackground()
11-12 13:05:16.982: E/AndroidRuntime(28094): at android.os.AsyncTask$3.done(AsyncTask.java:278)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
11-12 13:05:16.982: E/AndroidRuntime(28094): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.lang.Thread.run(Thread.java:856)
11-12 13:05:16.982: E/AndroidRuntime(28094): Caused by: java.lang.NullPointerException
11-12 13:05:16.982: E/AndroidRuntime(28094): at com.example.mysqltest.Login$AttemptLogin.doInBackground(Login.java:125)
11-12 13:05:16.982: E/AndroidRuntime(28094): at com.example.mysqltest.Login$AttemptLogin.doInBackground(Login.java:1)
11-12 13:05:16.982: E/AndroidRuntime(28094): at android.os.AsyncTask$2.call(AsyncTask.java:264)
11-12 13:05:16.982: E/AndroidRuntime(28094): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
11-12 13:05:16.982: E/AndroidRuntime(28094): ... 5 more
答案 0 :(得分：1)
我相信您正在移动应用程序中测试它，您是否考虑关闭防火墙并关闭PC中的任何防病毒程序？
答案 1 :(得分：0)
试试如下：
@Override
protected String doInBackground(String... args) {
if (success == 1) {
Log.d("Login Successful!", json.toString());
// save user data
SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(Login.this);
Editor edit = sp.edit();
edit.putString("username", username);
edit.commit();
} else {
Log.d("Login Failure!", json.getString(TAG_MESSAGE));
}
return json.getString(TAG_MESSAGE);
}
@Override
protected void onPostExecute(String file_url) {
// dismiss the dialog once product deleted
pDialog.dismiss();
if (file_url != null) {
Toast.makeText(Login.this, file_url, Toast.LENGTH_LONG).show();
Intent i = new Intent(Login.this, ReadComments.class);
startActivity(i);
}
}