1
내가 전에 활동 로그인json 결과가 null입니다. 어떻게 JSON을 확인하는 것은
package com.app.DatabaseSample;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.app.library.DatabaseHandler;
import com.app.library.UserFunctions;
public class LoginActivity extends Activity {
Button btnLogin;
Button btnLinkToRegister;
EditText inputUsername;
EditText inputPassword;
TextView loginErrorMsg;
// JSON Response node names
private static String KEY_SUCCESS = "success";
private static String KEY_ERROR = "error";
private static String KEY_ERROR_MSG = "error_msg";
private static String KEY_USER_ID = "userid";
private static String KEY_UID = "uid";
private static String KEY_NAME = "name";
private static String KEY_EMAIL = "email";
private static String KEY_CREATED_AT = "created_at";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.login);
// Importing all assets like buttons, text fields
inputUsername = (EditText) findViewById(R.id.loginUsername);
inputPassword = (EditText) findViewById(R.id.loginPassword);
btnLogin = (Button) findViewById(R.id.btnLogin);
loginErrorMsg = (TextView) findViewById(R.id.login_error);
// Login button Click Event
btnLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
readLogin(view);
}
});
}
private class ProcessLogin extends AsyncTask<String, String, JSONObject> {
private ProgressDialog dialog;
private ProgressDialog pDialog;
protected Context applicationContext;
String email,password;
@Override
protected void onPreExecute() {
super.onPreExecute();
inputUsername = (EditText) findViewById(R.id.loginUsername);
inputPassword = (EditText) findViewById(R.id.loginPassword);
email = inputUsername.getText().toString();
password = inputPassword.getText().toString();
pDialog = new ProgressDialog(LoginActivity.this);
pDialog.setMessage("Loading User ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected JSONObject doInBackground(String... args) {
UserFunctions userFunction = new UserFunctions();
JSONObject json = userFunction.loginUser(email, password);
Log.d("Button", "Login");
return json;
}
@Override
protected void onPostExecute(JSONObject json) {
// dismiss the dialog after getting all products
pDialog.dismiss();
UserFunctions userFunction = new UserFunctions();
try {
if(!json.has(KEY_SUCCESS)){
Toast.makeText(getApplicationContext(), "No more data",
Toast.LENGTH_LONG).show();
}
else if (json.getString(KEY_SUCCESS) != null){
loginErrorMsg.setText("");
String res = json.getString(KEY_SUCCESS);
if(Integer.parseInt(res) == 1){
// user successfully logged in
// Store user details in SQLite Database
DatabaseHandler db = new DatabaseHandler(getApplicationContext());
JSONObject json_user = json.getJSONObject("user");
// Clear all previous data in database
userFunction.logoutUser(getApplicationContext());
db.addUser(json_user.getString(KEY_USER_ID), json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT));
// Launch Dashboard Screen
Intent dashboard = new Intent(getApplicationContext(), DatabaseSample.class);
// Close all views before launching Dashboard
dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(dashboard);
// Close Login Screen
finish();
}else{
// Error in login
loginErrorMsg.setText("Username atau Password salah!");
}
}
else {
loginErrorMsg.setText("koneksi gagal ke server");
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
public void readLogin(View view) {
new ProcessLogin().execute();
// check for login response
}
}
가 null의 경우, onPostExecute는 힘이 가까운 JSON 결과가 null의 원인, JSON을 확인하는 방법 전에 if (json.getString(KEY_SUCCESS) != null)을 실행 onPostExecute의 null? 그래서 응용 프로그램은 가까운 강요하지 결과가 null 일 때?
이 내 로그 캣
01-23 01:05:29.851: E/AndroidRuntime(4513): FATAL EXCEPTION: main
01-23 01:05:29.851: E/AndroidRuntime(4513): java.lang.NullPointerException
01-23 01:05:29.851: E/AndroidRuntime(4513): at com.app.DatabaseSample.LoginActivity$ProcessLogin.onPostExecute(LoginActivity.java:108)
01-23 01:05:29.851: E/AndroidRuntime(4513): at com.app.DatabaseSample.LoginActivity$ProcessLogin.onPostExecute(LoginActivity.java:1)
01-23 01:05:29.851: E/AndroidRuntime(4513): at android.os.AsyncTask.finish(AsyncTask.java:417)
01-23 01:05:29.851: E/AndroidRuntime(4513): at android.os.AsyncTask.access$300(AsyncTask.java:127)
01-23 01:05:29.851: E/AndroidRuntime(4513): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429)
01-23 01:05:29.851: E/AndroidRuntime(4513): at android.os.Handler.dispatchMessage(Handler.java:99)
01-23 01:05:29.851: E/AndroidRuntime(4513): at android.os.Looper.loop(Looper.java:130)
01-23 01:05:29.851: E/AndroidRuntime(4513): at android.app.ActivityThread.main(ActivityThread.java:3683)
01-23 01:05:29.851: E/AndroidRuntime(4513): at java.lang.reflect.Method.invokeNative(Native Method)
01-23 01:05:29.851: E/AndroidRuntime(4513): at java.lang.reflect.Method.invoke(Method.java:507)
01-23 01:05:29.851: E/AndroidRuntime(4513): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
01-23 01:05:29.851: E/AndroidRuntime(4513): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
01-23 01:05:29.851: E/AndroidRuntime(4513): at dalvik.system.NativeStart.main(Native Method)
방금 만든대로 json1이 비어 있습니다. – njzk2