Android 异步任务结束后启动意图

我为我的Android应用程序创建了一个登录活动。用户输入正确的凭据后，登录活动将切换到主页，但我不知道为什么我的代码不会切换，并且我的logcat中没有显示错误。清单也被正确定义

这是我的登录活动：

public class LoginEmployerActivity extends Activity { 
Button btnLoginEmployer; 
Button btnLinkToEmployerRegisterScreen; 
EditText inputEmail; 
EditText inputPassword; 
TextView loginErrorMsg; 
TextView forgotPassword; 

// 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_UID = "uid"; 
private static String KEY_NAME = "name"; 
private static String KEY_CNAME = "cname"; 
private static String KEY_EMAIL = "email"; 
private static String KEY_CREATED_AT = "created_at"; 
private ProgressDialog pDialog; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.login_employer); 

// Importing all assets like buttons, text fields 
inputEmail = (EditText) findViewById(R.id.loginEmployerEmail); 
inputPassword = (EditText) findViewById(R.id.loginEmployerPassword); 
btnLoginEmployer = (Button) findViewById(R.id.btnLoginEmployer); 
btnLinkToEmployerRegisterScreen = (Button) findViewById(R.id.btnLinkToEmployerRegisterScreen); 
loginErrorMsg = (TextView) findViewById(R.id.login_error); 
forgotPassword = (TextView) findViewById(R.id.link_to_forgetPassword); 

// Login button Click Event 
btnLoginEmployer.setOnClickListener(new View.OnClickListener() { 

    public void onClick(View view) { 
        // Checking for server respond 
            new LoginEmployer().execute(); 
        } 
    } 
}); 

// Link to Register Screen 
btnLinkToEmployerRegisterScreen 
        .setOnClickListener(new View.OnClickListener() { 

            public void onClick(View view) { 
                Intent i = new Intent(getApplicationContext(), 
                        RegisterEmployerActivity.class); 
                startActivity(i); 
                finish(); 
            } 
        }); 

// Link to forgot password link 
forgotPassword.setOnClickListener(new View.OnClickListener() { 
    public void onClick(View view) { 
        // Switching to forgot password screen 
        Intent i = new Intent(getApplicationContext(), 
                ForgotPasswordEmployerActivity.class); 
        startActivity(i); 
    } 
}); 
} 

// Background ASYNC Task to login by making HTTP Request 
class LoginEmployer extends AsyncTask<String, String, String> { 

// Before starting background thread Show Progress Dialog 
@Override 
protected void onPreExecute() { 
    super.onPreExecute(); 
    pDialog = new ProgressDialog(LoginEmployerActivity.this); 
    pDialog.setMessage("Authenticating..."); 
    pDialog.setIndeterminate(false); 
    pDialog.setCancelable(false); 
    pDialog.show(); 
} 

// Checking login in background 
protected String doInBackground(String... params) { 
    runOnUiThread(new Runnable() { 
        public void run() { 

            String email = inputEmail.getText().toString(); 
            String password = inputPassword.getText().toString(); 
            EmployerFunctions employerFunctions = new EmployerFunctions(); 
            JSONObject json = employerFunctions.loginUser(email, 
                    password); 

            // check for login response 
            try { 
                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 
                        DatabaseHandlerEmployer dbe = new DatabaseHandlerEmployer( 
                                getApplicationContext()); 
                        JSONObject json_user = json 
                                .getJSONObject("user"); 

                        // Clear all previous data in database 
                        employerFunctions 
                                .logoutUser(getApplicationContext()); 
                        dbe.addUser( 
                                json_user.getString(KEY_NAME), 
                                //json_user.getString(KEY_CNAME), 
                                json_user.getString(KEY_EMAIL), 
                                json.getString(KEY_UID), 
                                json_user.getString(KEY_CREATED_AT)); 
                        // Launch Employer homePage Screen 
                        Intent homepage = new Intent( 
                                getApplicationContext(), 
                                HomepageEmployerActivity.class); 

                        // Close all views before launching Employer 
                        // homePage 
                        homepage.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
                        startActivity(homepage); 

                        // Close Login Screen 
                        finish(); 
                    } else { 
                        // Error in login 
                        loginErrorMsg 
                                .setText("Invalid username/password"); 
                    } 
                } 
            } catch (JSONException e) { 
                e.printStackTrace(); 
            } 
        } 
    }); 
    return null; 
} 

// After completing background task Dismiss the progress dialog 
protected void onPostExecute(String file_url) { 
    // dismiss the dialog once done 
    pDialog.dismiss(); 
} 
} 
}

公共类LoginEmployerActivity扩展活动{
按钮BTN工程师；
按钮btnLinkToEmployerRegisterScreen；
编辑文本输入电子邮件；
编辑文本输入密码；
TextView loginErrorMsg；
文本视图放弃密码；
//JSON响应节点名称
私有静态字符串密钥\u SUCCESS=“SUCCESS”；
私有静态字符串密钥\u ERROR=“ERROR”；
私有静态字符串密钥\u ERROR\u MSG=“ERROR\u MSG”；
私有静态字符串密钥\u UID=“UID”；
私有静态字符串密钥\u NAME=“NAME”；
私有静态字符串密钥\u CNAME=“CNAME”；
私有静态字符串密钥\u EMAIL=“EMAIL”；
私有静态字符串密钥\u CREATED\u AT=“CREATED\u AT”；
私人对话；
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.login\u雇主）；
//导入按钮、文本字段等所有资源
inputEmail=（EditText）findViewById（R.id.loginEmployerEmail）；
inputPassword=（EditText）findViewById（R.id.loginEmployerPassword）；
btnEngineemployer=（按钮）findViewById（R.id.btnEngineemployer）；
btnLinkToEmployerRegisterScreen=（按钮）findViewById（R.id.btnLinkToEmployerRegisterScreen）；
loginErrorMsg=（TextView）findViewById（R.id.login\u错误）；
forgotPassword=（TextView）findViewById（R.id.link\u to\u forgetPassword）；
//登录按钮点击事件
btnlogenemployer.setOnClickListener（新视图.OnClickListener（）{
public void onClick（视图）{
//检查服务器响应
新的LoginEmployer（）.execute（）；
} 
} 
}); 
//链接到注册屏幕
btnLinkToEmployerRegisterScreen
.setOnClickListener（新视图.OnClickListener（）{
public void onClick（视图）{
意图i=新意图（getApplicationContext（），
RegisterEmployerActivity.class）；
星触觉（i）；
完成（）；
} 
}); 
//链接到忘记密码链接
forgotPassword.setOnClickListener（新视图.OnClickListener（）{
public void onClick（视图）{
//切换到忘记密码屏幕
意图i=新意图（getApplicationContext（），
ForgotPasswordEmployerActivity.class）；
星触觉（i）；
} 
}); 
} 
//通过发出HTTP请求登录的后台异步任务
类LoginEmployer扩展异步任务{
//在启动后台线程显示进度对话框之前
@凌驾
受保护的void onPreExecute（）{
super.onPreExecute（）；
pDialog=新建进度对话框（LoginEmployerActivity.this）；
设置消息（“正在验证…”）；
pDialog.setUndeterminate（假）；
pDialog.setCancelable（假）；
pDialog.show（）；
} 
//在后台检查登录
受保护的字符串doInBackground（字符串…参数）{
runOnUiThread（新的Runnable（）{
public void run（）{
字符串email=inputEmail.getText（）.toString（）；
字符串密码=inputPassword.getText（）.toString（）；
EmployerFunctions EmployerFunctions=新EmployerFunctions（）；
JSONObject json=employerFunctions.loginUser（电子邮件，
密码）；
//检查登录响应
试试{
if（json.getString（KEY_SUCCESS）！=null）{
loginErrorMsg.setText（“”）；
String res=json.getString（KEY_SUCCESS）；
如果（Integer.parseInt（res）==1{
//用户已成功登录
//在SQLite数据库中存储用户详细信息
DatabaseHandlerEmployer dbe=新的DatabaseHandlerEmployer（
getApplicationContext（））；
JSONObject json_user=json
.getJSONObject（“用户”）；
//清除数据库中以前的所有数据
雇员职能
.logoutUser（getApplicationContext（））；
dbe.addUser（
json_user.getString（KEY_NAME），
//json_user.getString（KEY_CNAME），
json_user.getString（KEY_电子邮件），
json.getString（KEY_UID），
json_user.getString（KEY_CREATED_AT））；
//启动雇主主页屏幕
意向主页=新意向（
getApplicationContext（），
主页EmployeerActivity.class）；
//启动前关闭所有视图
//主页
主页。添加标志（意图。标志\活动\清除\顶部）；
startActivity（主页）；
//关闭登录屏幕
完成（）；
}否则{
//登录错误
登录者
.setText（“无效用户名/密码”）；
} 
} 
}捕获（JSONException e）{
e、 printStackTrace（）；
} 
} 
}); 
返回null；
} 
//完成后台任务后，关闭“进度”对话框
受保护的void onPostExecute（字符串文件\u url）{
//完成后关闭对话框
pDialog.disclose（）；
} 
} 
}

将INTENT语句移动到onPostExecute方法后编辑的代码

public class LoginEmployerActivity extends Activity {
Button btnLoginEmployer;
Button btnLinkToEmployerRegisterScreen;
EditText inputEmail;
EditText inputPassword;
TextView loginErrorMsg;
TextView forgotPassword;

// 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_UID = "uid";
private static String KEY_NAME = "name";
private static String KEY_CNAME = "cname";
private static String KEY_EMAIL = "email";
private static String KEY_CREATED_AT = "created_at";
private ProgressDialog pDialog;

boolean loginVerify= false;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.login_employer);

    // Importing all assets like buttons, text fields
    inputEmail = (EditText) findViewById(R.id.loginEmployerEmail);
    inputPassword = (EditText) findViewById(R.id.loginEmployerPassword);
    btnLoginEmployer = (Button) findViewById(R.id.btnLoginEmployer);
    btnLinkToEmployerRegisterScreen = (Button) findViewById(R.id.btnLinkToEmployerRegisterScreen);
    loginErrorMsg = (TextView) findViewById(R.id.login_error);
    forgotPassword = (TextView) findViewById(R.id.link_to_forgetPassword);

    // Login button Click Event
    btnLoginEmployer.setOnClickListener(new View.OnClickListener() {

        public void onClick(View view) {
            // Checking for server respond
                new LoginEmployer().execute();
            }
        }
    });

    // Link to Register Screen
    btnLinkToEmployerRegisterScreen
            .setOnClickListener(new View.OnClickListener() {

                public void onClick(View view) {
                    Intent i = new Intent(getApplicationContext(),
                            RegisterEmployerActivity.class);
                    startActivity(i);
                    finish();
                }
            });

    // Link to forgot password link
    forgotPassword.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {
            // Switching to forgot password screen
            Intent i = new Intent(getApplicationContext(),
                    ForgotPasswordEmployerActivity.class);
            startActivity(i);
        }
    });
}

// Background ASYNC Task to login by making HTTP Request
class LoginEmployer extends AsyncTask<String, String, String> {

    // Before starting background thread Show Progress Dialog
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(LoginEmployerActivity.this);
        pDialog.setMessage("Authenticating...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    // Checking login in background
    protected String doInBackground(String... params) {
        runOnUiThread(new Runnable() {
            public void run() {

                String email = inputEmail.getText().toString();
                String password = inputPassword.getText().toString();
                EmployerFunctions employerFunctions = new EmployerFunctions();
                JSONObject json = employerFunctions.loginUser(email,
                        password);

                // check for login response
                try {
                    if (json.getString(KEY_SUCCESS) != null) {
                        loginErrorMsg.setText("");
                        String res = json.getString(KEY_SUCCESS);
                        if (Integer.parseInt(res) == 1) {
                            loginVerify = true;
                            // user successfully logged in
                            // Store user details in SQLite Database
                            DatabaseHandlerEmployer dbe = new DatabaseHandlerEmployer(
                                    getApplicationContext());
                            JSONObject json_user = json
                                    .getJSONObject("user");

                            // Clear all previous data in database
                            employerFunctions
                                    .logoutUser(getApplicationContext());
                            dbe.addUser(
                                    json_user.getString(KEY_NAME),
                                    json_user.getString(KEY_CNAME),
                                    json_user.getString(KEY_EMAIL),
                                    json.getString(KEY_UID),
                                    json_user.getString(KEY_CREATED_AT));

                        } else {
                            // Error in login
                            loginErrorMsg
                                    .setText("Invalid username/password");
                        }
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        });
        return null;
    }

    // After completing background task Dismiss the progress dialog
    protected void onPostExecute(String file_url) {
        // dismiss the dialog once done
        pDialog.dismiss();
        if ( loginVerify == true ) 
        {
        // Launch Employer homePage Screen
        Intent homepage = new Intent(getApplicationContext(),
                HomepageEmployerActivity.class);

        // Close all views before launching Employer
        // homePage
        homepage.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        startActivity(homepage);

        // Close Login Screen
        finish();
        }
    }
}

public类LoginEmployerActivity扩展活动{
按钮BTN工程师；
按钮btnLinkToEmployerRegisterScreen；
编辑文本输入电子邮件；
E
protected void onPostExecute(String file_url) { 

    // dismiss the dialog once done             // Intent Code Missing.

    pDialog.dismiss(); 

Intent homepage = new Intent( getApplicationContext(), HomepageEmployerActivity.class); 
homepage.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
startActivity(homepage);

if(loginVerifed == true)
{
       Intent homepage = new Intent(getApplicationContext(),HomepageEmployerActivity.class                               
       homepage.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
       startActivity(homepage);
       finish();
}

// Background ASYNC Task to login by making HTTP Request 
class LoginEmployer extends AsyncTask<String, String, String> { 

boolean validUser = false;

 if (Integer.parseInt(res) == 1) { 
      // user successfully logged in 
      // Store user details in SQLite Database 

     validUser = true;  //set valid to true

protected void onPostExecute(String file_url) { 
    // dismiss the dialog once done 
    pDialog.dismiss(); 
    if ( validUser )
    {
        Intent homepage = new Intent( LoginEmployerActivity.this, 
        HomepageEmployerActivity.class); 

        // Close all views before launching Employer 
        // homePage 
         homepage.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
         startActivity(homepage); 
    }