java不能将片段和活动登录结合起来
我刚从片段开始,想学习如何使用滑动菜单制作更多功能性应用程序,但我在setcontentview
上出错,因为我想制作一个登录屏幕,这是一个活动。
链接到我的教程。
幻灯片菜单:
安卓 sliding menu
和登录屏幕:
安卓 login and register
public class LoginActivity extends Fragment {
public LoginActivity() {
// Required empty public constructor
}
private static final String TAG = RegisterActivity.class.getSimpleName();
private Button btnLogin;
private Button btnLinkToRegister;
private EditText inputEmail;
private EditText inputPassword;
private ProgressDialog pDialog;
private SessionManager session;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_login);
inputEmail = (EditText) getView().findViewById(R.id.email);
inputPassword = (EditText) getView().findViewById(R.id.password);
btnLogin = (Button) getView().findViewById(R.id.btnLogin);
btnLinkToRegister = (Button) getView().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(LoginActivity.this, LoginMainActivity.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(),
RegisterActivity.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,
AppConfig.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(LoginActivity.this,
LoginMainActivity.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();
} `
我在:-setContentView
处得到错误
- pDialog = new ProgressDialog(this);
- session = new SessionManager(getApplicationContext());
- Intent intent = new Intent(LoginActivity.this, LoginMainActivity.class);
startActivity(intent);
finish();
# 1 楼答案
您混合了
Activity
和Fragment
。如果使用setContentView
,则必须扩展Activity
。 此外,您还会在此处遇到一个错误:因为
LoginActivity
是一个片段。 还有,这里将
LoginActivity
的超类更改为Activity
后,将getApplicationContext
更改为LoginActivity.this