我有一个带有按钮的活动，当用户点击按钮时，将出现一个AlertDialog，其中包含2个EditText，您可以在其中输入电子邮件和密码以进行登录。 当我尝试从EditText中获取文本时，我总是只得到空字符串。 login_alert布局是AlertDialog的布局。 以下是代码：
View view = getLayoutInflater().inflate(R.layout.login_alert, null, false);
String email = ((EditText) view.findViewById(R.id.emailEditText)).getText().toString();
String password = ((EditText) view.findViewById(R.id.passwordEditText)).getText().toString();
System.out.println("DEBUG: "+email+", "+password); // Empty strings
编辑： 活动代码：
public class MainActivity extends FragmentActivity {
public static final String mAPP_ID = "...";
public static final String USER_DB_URL = "...";
AssetsExtracter mTask;
private MainFragment mainFragment;
private List<User> usersList = new ArrayList<User>();
private User currentUser = null;
private Button labLoginButton;
private EditText emailET;
private EditText passwordET;
private ProgressDialog dialog;
private View alertView; /* THIS IS THE SOLUTION */
boolean userIsLogged = false;
static {
IMetaioSDKAndroid.loadNativeLibs();
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
setContentView(R.layout.activity_main);
/*View view = getLayoutInflater().inflate(R.layout.login_alert, null, false); BEFORE*/
alertView = getLayoutInflater().inflate(R.layout.login_alert, null, false);
emailET = (EditText) view.findViewById(R.id.emailEditText);
passwordET = (EditText) view.findViewById(R.id.passwordEditText);
labLoginButton = (Button) findViewById(R.id.loginLabButton);
updateLoginButton();
dialog = new ProgressDialog(this);
dialog.setMessage("Signin in...");
if (savedInstanceState == null) {
// Add the fragment on initial activity setup
mainFragment = new MainFragment();
getSupportFragmentManager().beginTransaction()
.add(android.R.id.content, mainFragment).commit();
} else {
// Or set the fragment from restored state info
mainFragment = (MainFragment) getSupportFragmentManager()
.findFragmentById(android.R.id.content);
}
mTask = new AssetsExtracter();
mTask.execute(0);
}
/* THIS METHOD IS CALLED BY THE LOGIN BUTTON IN THE MAIN ACTIVITY LAYOUT */
public void onLabLoginButtonClick(View v) {
if (userIsLogged) {
currentUser = null;
userIsLogged = false;
updateLoginButton();
Toast.makeText(this, "Disconnected from Lab", Toast.LENGTH_SHORT)
.show();
} else {
/*View messageView = getLayoutInflater().inflate(
R.layout.login_alert, null, false); BEFORE */
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setIcon(R.drawable.icon_launcher);
builder.setTitle(R.string.login_string);
builder.setView(alertView); /* USING THE GLOBAL VARIABLE */
builder.setPositiveButton("Sign me", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface d, int which) {
dialog.show();
// Download user and return a List of User
DownloadFilesAsyncTask task = new DownloadFilesAsyncTask(USER_DB_URL) {
@Override
protected void onPostExecute(final List<User> result) {
usersList = result;
loginCheckRoutine(); //HERE I MANAGE THE LOGIN AND GETTING EMPTY STRING
}
};
task.execute();
}
});
builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
});
builder.create();
builder.show();
}
}
public void updateLoginButton() {
if (userIsLogged) {
labLoginButton.setText(R.string.logout_string);
} else {
labLoginButton.setText(R.string.login_string);
}
}
public void loginCheckRoutine() {
String email = emailET.getText().toString();
String password = passwordET.getText().toString();
System.out.println("DEBUG: " + email + ", " + password); // EMPTY
// controllo nella lista se c'è l'utente coi dati inseriti
for (int i = 0; i < usersList.size(); i++) {
if (usersList.get(i).getEmail().equals(email)
&& password.equals("admin")) {
currentUser = usersList.get(i);
userIsLogged = true;
updateLoginButton();
dialog.dismiss();
break;
}
}
if (!userIsLogged) {
userIsLogged = false;
updateLoginButton();
dialog.dismiss();
Toast.makeText(MainActivity.this, "Login Failed",
Toast.LENGTH_SHORT).show();
}
}
}
问题已解决，解决方案： 在onCreate()中，我将alert_dialog布局填充到一个View变量中。我将该View变量作为全局变量（在onCreate()之前），然后在onLabLoginButtonClick()中，我不再重新填充视图，而是使用在onCreate()中实例化的全局变量。希望这很清楚。谢谢大家！