Android 用户登录凭证不存在'；登录后不会显示在登录页（主页）
我从github获得了用户登录模板。我对它进行了一些修改以满足我的需要，但没有修改任何重要的代码 问题1：如果我注册并登录，页面将转到activity_主类（登录页面），并显示我的登录凭据（姓名和电子邮件）。但是，如果我注销并再次登录，登录页上不会显示凭据。第一次它显示下一次从来没有 问题2：如果我注册了一个新ID，但使用任何已注册的旧ID登录（注册新ID后立即登录），登录页将显示新注册ID的凭据。之后，如果我使用任何ID登录，它将不会显示 我想做的是：无论何时登录，用户凭证都会显示在登录页上。还有一个问题需要解决 任何帮助都将被感谢 登录页面代码：Android 用户登录凭证不存在'；登录后不会显示在登录页（主页）,android,Android,我从github获得了用户登录模板。我对它进行了一些修改以满足我的需要，但没有修改任何重要的代码 问题1：如果我注册并登录，页面将转到activity_主类（登录页面），并显示我的登录凭据（姓名和电子邮件）。但是，如果我注销并再次登录，登录页上不会显示凭据。第一次它显示下一次从来没有 问题2：如果我注册了一个新ID，但使用任何已注册的旧ID登录（注册新ID后立即登录），登录页将显示新注册ID的凭据。之后，如果我使用任何ID登录，它将不会显示 我想做的是：无论何时登录，用户凭证都会显示在登录页上。
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
inputEmail = (EditText) findViewById(R.id.email);
inputPassword = (EditText) findViewById(R.id.password);
btnLogin = (Button) findViewById(R.id.btnLogin);
btnLinkToRegister = (Button) findViewById(R.id.btnLinkToRegisterScreen);
// Progress dialog
pDialog = new ProgressDialog(this);
pDialog.setCancelable(false);
// Session manager
session = new SessionManager(getApplicationContext());
// Check if user is already logged in or not
if (session.isLoggedIn()) {
// User is already logged in. Take him to main activity
Intent intent = new Intent(Activity_Login.this, Activity_Main.class);
startActivity(intent);
finish();
}
// Login button Click Event
btnLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String email = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
// Check for empty data in the form
if (email.trim().length() > 0 && password.trim().length() > 0) {
// login user
checkLogin(email, password);
} else {
// Prompt user to enter credentials
Toast.makeText(getApplicationContext(),
"Please enter the credentials!", Toast.LENGTH_LONG)
.show();
}
}
});
// Link to Register Screen
btnLinkToRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
Activity_Register.class);
startActivity(i);
finish();
}
});
}
/**
* function to verify login details in mysql db
* */
private void checkLogin(final String email, final String password) {
// Tag used to cancel the request
String tag_string_req = "req_login";
pDialog.setMessage("Logging in ...");
showDialog();
StringRequest strReq = new StringRequest(Method.POST,
Config_URL.URL_REGISTER, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "Login Response: " + response.toString());
hideDialog();
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
// Check for error node in json
if (!error) {
// user successfully logged in
// Create login session
session.setLogin(true);
// Launch main activity
Intent intent = new Intent(Activity_Login.this,
Activity_Main.class);
startActivity(intent);
finish();
} else {
// Error in login. Get the error message
String errorMsg = jObj.getString("error_msg");
Toast.makeText(getApplicationContext(),
errorMsg, Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Login Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
error.getMessage(), Toast.LENGTH_LONG).show();
hideDialog();
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting parameters to login url
Map<String, String> params = new HashMap<String, String>();
params.put("tag", "login");
params.put("email", email);
params.put("password", password);
return params;
}
};
// Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
inputFullName = (EditText) findViewById(R.id.name);
inputEmail = (EditText) findViewById(R.id.email);
inputPassword = (EditText) findViewById(R.id.password);
inputNumber = (EditText) findViewById(R.id.number);
btnRegister = (Button) findViewById(R.id.btnRegister);
btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen);
// Progress dialog
pDialog = new ProgressDialog(this);
pDialog.setCancelable(false);
// Session manager
session = new SessionManager(getApplicationContext());
// SQLite database handler
db = new SQLiteHandler(getApplicationContext());
// Check if user is already logged in or not
if (session.isLoggedIn()) {
// User is already logged in. Take him to main activity
Intent intent = new Intent(Activity_Register.this,
Activity_Main.class);
startActivity(intent);
finish();
}
// Register Button Click event
btnRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String name = inputFullName.getText().toString();
String email = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
String number = inputNumber.getText().toString();
if (!name.isEmpty() && !email.isEmpty() && !password.isEmpty() && !number.isEmpty()) {
registerUser(name, email, password, number);
} else {
Toast.makeText(getApplicationContext(),
"Please enter your details!", Toast.LENGTH_LONG)
.show();
}
}
});
// Link to Login Screen
btnLinkToLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
Activity_Login.class);
startActivity(i);
finish();
}
});
}
/**
* Function to store user in MySQL database will post params(tag, name,
* email, password) to register url
* */
private void registerUser(final String name, final String email,
final String password, final String number) {
// Tag used to cancel the request
String tag_string_req = "req_register";
pDialog.setMessage("Registering ...");
showDialog();
StringRequest strReq = new StringRequest(Method.POST,
Config_URL.URL_REGISTER, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "Register Response: " + response.toString());
hideDialog();
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
if (!error) {
// User successfully stored in MySQL
// Now store the user in sqlite
String uid = jObj.getString("uid");
JSONObject user = jObj.getJSONObject("user");
String name = user.getString("name");
String email = user.getString("email");
String created_at = user
.getString("created_at");
// Inserting row in users table
db.addUser(name, email, uid, created_at);
// Launch login activity
Intent intent = new Intent(
Activity_Register.this,
Activity_Login.class);
startActivity(intent);
finish();
} else {
// Error occurred in registration. Get the error
// message
String errorMsg = jObj.getString("error_msg");
Toast.makeText(getApplicationContext(),
errorMsg, Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Registration Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
error.getMessage(), Toast.LENGTH_LONG).show();
hideDialog();
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting params to register url
Map<String, String> params = new HashMap<String, String>();
params.put("tag", "register");
params.put("name", name);
params.put("email", email);
params.put("password", password);
params.put("number", number);
return params;
}
};
// Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
}
public class Activity_Main extends Activity {
private TextView txtName;
private TextView txtEmail;
private Button btnLogout;
private SQLiteHandler db;
private SessionManager session;
public Button booknow;
public void init(){
booknow= (Button) findViewById(R.id.booknow);
booknow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent toy = new Intent(Activity_Main.this,BikeEntryActivity.class);
startActivity(toy);
}
});
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
txtName = (TextView) findViewById(R.id.name);
txtEmail = (TextView) findViewById(R.id.email);
btnLogout = (Button) findViewById(R.id.btnLogout);
// SqLite database handler
db = new SQLiteHandler(getApplicationContext());
// session manager
session = new SessionManager(getApplicationContext());
if (!session.isLoggedIn()) {
logoutUser();
}
// Fetching user details from sqlite
HashMap<String, String> user = db.getUserDetails();
String name = user.get("name");
String email = user.get("email");
// Displaying the user details on the screen
txtName.setText(name);
txtEmail.setText(email);
// Logout button click event
btnLogout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
logoutUser();
}
});
}
/**
* Logging out the user. Will set isLoggedIn flag to false in shared
* preferences Clears the user data from sqlite users table
* */
private void logoutUser() {
session.setLogin(false);
db.deleteUsers();
// Launching the login activity
Intent intent = new Intent(Activity_Main.this, Activity_Login.class);
startActivity(intent);
finish();
}
}
@覆盖
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity\u登录）；
inputEmail=（EditText）findViewById（R.id.email）；
inputPassword=（EditText）findViewById（R.id.password）；
btnLogin=（按钮）findViewById（R.id.btnLogin）；
btnLinkToRegister=（按钮）findViewById（R.id.btnLinkToRegister屏幕）；
//进度对话框
pDialog=新建进度对话框（此对话框）；
pDialog.setCancelable（假）；
//会话管理器
session=newsessionmanager（getApplicationContext（））；
//检查用户是否已登录
if（session.isLoggedIn（））{
//用户已登录。请将其带到主活动
意向意向=新意向（Activity\u Login.this，Activity\u Main.class）；
星触觉（意向）；
完成（）；
}
//登录按钮点击事件
btnLogin.setOnClickListener（新视图.OnClickListener（）{
公共void onClick（视图）{
字符串email=inputEmail.getText（）.toString（）；
字符串密码=inputPassword.getText（）.toString（）；
//检查表单中是否有空数据
if（email.trim（）.length（）>0&&password.trim（）.length（）>0）{
//登录用户
检查登录（电子邮件、密码）；
}否则{
//提示用户输入凭据
Toast.makeText（getApplicationContext（），
“请输入凭据！”，Toast.LENGTH\u LONG）
.show（）；
}
}
});
//链接到注册屏幕
btnLinkToRegister.setOnClickListener（新视图.OnClickListener（）{
公共void onClick（视图）{
意图i=新意图（getApplicationContext（），
活动(注册类别);；
星触觉（i）；
完成（）；
}
});
}
/**
*函数验证mysql数据库中的登录详细信息
* */
私有void checkLogin（最终字符串电子邮件、最终字符串密码）{
//用于取消请求的标记
String tag\u String\u req=“req\u login”；
设置消息（“登录…”）；
showDialog（）；
StringRequest strReq=新的StringRequest（Method.POST，
Config_URL.URL_寄存器，new Response.Listener（）{
@凌驾
公共void onResponse（字符串响应）{
Log.d（标记“登录响应：+Response.toString（））；
hideDialog（）；
试一试{
JSONObject jObj=新的JSONObject（响应）；
布尔错误=jObj.getBoolean（“错误”）；
//检查json中的错误节点
如果（！错误）{
//用户已成功登录
//创建登录会话
session.setLogin（true）；
//开展主要活动
意向意向=新意向（活动\登录此，
活动（主要课程）；
星触觉（意向）；
完成（）；
}否则{
//登录时出错。获取错误消息
String errorMsg=jObj.getString（“error_msg”）；
Toast.makeText（getApplicationContext（），
errorMsg，Toast.LENGTH_LONG）.show（）；
}
}捕获（JSONException e）{
//JSON错误
e、 printStackTrace（）；
}
}
}，new Response.ErrorListener（）{
@凌驾
公共无效onErrorResponse（截击错误）{
Log.e（标记“登录错误：+Error.getMessage（））；
Toast.makeText（getApplicationContext（），
error.getMessage（），Toast.LENGTH_LONG）.show（）；
hideDialog（）；
}
}) {
@凌驾
受保护的映射getParams（）{
//将参数发布到登录url
Map params=新的HashMap（）；
参数put（“标记”、“登录”）；
参数put（“电子邮件”，电子邮件）；
参数put（“密码”，密码）；
返回参数；
}
};
//将请求添加到请求队列
AppController.getInstance（）.addToRequestQueue（streq，标记字符串请求）；
}
私有void showDialog（）{
如果（！pDialog.isShowing（））
pDialog.show（）；
}
私有void hideDialog（）{
if（pDialog.isShowing（））
pDialog.disclose（）；
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
inputEmail = (EditText) findViewById(R.id.email);
inputPassword = (EditText) findViewById(R.id.password);
btnLogin = (Button) findViewById(R.id.btnLogin);
btnLinkToRegister = (Button) findViewById(R.id.btnLinkToRegisterScreen);
// Progress dialog
pDialog = new ProgressDialog(this);
pDialog.setCancelable(false);
// Session manager
session = new SessionManager(getApplicationContext());
// Check if user is already logged in or not
if (session.isLoggedIn()) {
// User is already logged in. Take him to main activity
Intent intent = new Intent(Activity_Login.this, Activity_Main.class);
startActivity(intent);
finish();
}
// Login button Click Event
btnLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String email = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
// Check for empty data in the form
if (email.trim().length() > 0 && password.trim().length() > 0) {
// login user
checkLogin(email, password);
} else {
// Prompt user to enter credentials
Toast.makeText(getApplicationContext(),
"Please enter the credentials!", Toast.LENGTH_LONG)
.show();
}
}
});
// Link to Register Screen
btnLinkToRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
Activity_Register.class);
startActivity(i);
finish();
}
});
}
/**
* function to verify login details in mysql db
* */
private void checkLogin(final String email, final String password) {
// Tag used to cancel the request
String tag_string_req = "req_login";
pDialog.setMessage("Logging in ...");
showDialog();
StringRequest strReq = new StringRequest(Method.POST,
Config_URL.URL_REGISTER, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "Login Response: " + response.toString());
hideDialog();
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
// Check for error node in json
if (!error) {
// user successfully logged in
// Create login session
session.setLogin(true);
// Launch main activity
Intent intent = new Intent(Activity_Login.this,
Activity_Main.class);
startActivity(intent);
finish();
} else {
// Error in login. Get the error message
String errorMsg = jObj.getString("error_msg");
Toast.makeText(getApplicationContext(),
errorMsg, Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Login Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
error.getMessage(), Toast.LENGTH_LONG).show();
hideDialog();
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting parameters to login url
Map<String, String> params = new HashMap<String, String>();
params.put("tag", "login");
params.put("email", email);
params.put("password", password);
return params;
}
};
// Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
inputFullName = (EditText) findViewById(R.id.name);
inputEmail = (EditText) findViewById(R.id.email);
inputPassword = (EditText) findViewById(R.id.password);
inputNumber = (EditText) findViewById(R.id.number);
btnRegister = (Button) findViewById(R.id.btnRegister);
btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen);
// Progress dialog
pDialog = new ProgressDialog(this);
pDialog.setCancelable(false);
// Session manager
session = new SessionManager(getApplicationContext());
// SQLite database handler
db = new SQLiteHandler(getApplicationContext());
// Check if user is already logged in or not
if (session.isLoggedIn()) {
// User is already logged in. Take him to main activity
Intent intent = new Intent(Activity_Register.this,
Activity_Main.class);
startActivity(intent);
finish();
}
// Register Button Click event
btnRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String name = inputFullName.getText().toString();
String email = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
String number = inputNumber.getText().toString();
if (!name.isEmpty() && !email.isEmpty() && !password.isEmpty() && !number.isEmpty()) {
registerUser(name, email, password, number);
} else {
Toast.makeText(getApplicationContext(),
"Please enter your details!", Toast.LENGTH_LONG)
.show();
}
}
});
// Link to Login Screen
btnLinkToLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
Activity_Login.class);
startActivity(i);
finish();
}
});
}
/**
* Function to store user in MySQL database will post params(tag, name,
* email, password) to register url
* */
private void registerUser(final String name, final String email,
final String password, final String number) {
// Tag used to cancel the request
String tag_string_req = "req_register";
pDialog.setMessage("Registering ...");
showDialog();
StringRequest strReq = new StringRequest(Method.POST,
Config_URL.URL_REGISTER, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "Register Response: " + response.toString());
hideDialog();
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
if (!error) {
// User successfully stored in MySQL
// Now store the user in sqlite
String uid = jObj.getString("uid");
JSONObject user = jObj.getJSONObject("user");
String name = user.getString("name");
String email = user.getString("email");
String created_at = user
.getString("created_at");
// Inserting row in users table
db.addUser(name, email, uid, created_at);
// Launch login activity
Intent intent = new Intent(
Activity_Register.this,
Activity_Login.class);
startActivity(intent);
finish();
} else {
// Error occurred in registration. Get the error
// message
String errorMsg = jObj.getString("error_msg");
Toast.makeText(getApplicationContext(),
errorMsg, Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Registration Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
error.getMessage(), Toast.LENGTH_LONG).show();
hideDialog();
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting params to register url
Map<String, String> params = new HashMap<String, String>();
params.put("tag", "register");
params.put("name", name);
params.put("email", email);
params.put("password", password);
params.put("number", number);
return params;
}
};
// Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
}
public class Activity_Main extends Activity {
private TextView txtName;
private TextView txtEmail;
private Button btnLogout;
private SQLiteHandler db;
private SessionManager session;
public Button booknow;
public void init(){
booknow= (Button) findViewById(R.id.booknow);
booknow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent toy = new Intent(Activity_Main.this,BikeEntryActivity.class);
startActivity(toy);
}
});
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
txtName = (TextView) findViewById(R.id.name);
txtEmail = (TextView) findViewById(R.id.email);
btnLogout = (Button) findViewById(R.id.btnLogout);
// SqLite database handler
db = new SQLiteHandler(getApplicationContext());
// session manager
session = new SessionManager(getApplicationContext());
if (!session.isLoggedIn()) {
logoutUser();
}
// Fetching user details from sqlite
HashMap<String, String> user = db.getUserDetails();
String name = user.get("name");
String email = user.get("email");
// Displaying the user details on the screen
txtName.setText(name);
txtEmail.setText(email);
// Logout button click event
btnLogout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
logoutUser();
}
});
}
/**
* Logging out the user. Will set isLoggedIn flag to false in shared
* preferences Clears the user data from sqlite users table
* */
private void logoutUser() {
session.setLogin(false);
db.deleteUsers();
// Launching the login activity
Intent intent = new Intent(Activity_Main.this, Activity_Login.class);
startActivity(intent);
finish();
}
}
@覆盖
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.activity\u寄存器）；
inputFullName=（编辑）