我正在尝试创建登录视图。
我＆＃39; d想要启动一个新的AsyncTask来执行对服务器的REST调用并显示progress bar。我需要UI main thread不会阻止，它必须显示带有消息的祝酒（如成功或失败），具体取决于AsyncTask返回的内容。
这里是代码：
SetupActivity（主线程）：
//Get reference SignUp Button
Button signupButton = (Button)myDialog.findViewById(R.id.button_signup_OK);
signupButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
//Get all the textfield content from the form
name=((EditText)myDialog.findViewById(R.id.nameEditText)).getText();
surname=((EditText)myDialog.findViewById(R.id.surnameEditText)).getText();
email=((EditText)myDialog.findViewById(R.id.emailEditText)).getText();
password=((EditText)myDialog.findViewById(R.id.passwordEditText)).getText();
password_Retyped=((EditText)myDialog.findViewById(R.id.passwordRepEditText)).getText();
//Get hash from password
hashPassword=DigestMd5.md5(password);
hashPasswordRep=DigestMd5.md5(password_Retyped);
//Check if the fields are null
if(name.toString().equals("")){
((EditText) myDialog.findViewById(R.id.nameEditText)).setError(getString(R.string.mandatoryField));
}
if(surname.toString().equals("")){
((EditText) myDialog.findViewById(R.id.surnameEditText)).setError(getString(R.string.mandatoryField));
}
if(email.toString().equals("") ){
((EditText) myDialog.findViewById(R.id.emailEditText)).setError(getString(R.string.mandatoryField));
}else{
if(!new EmailValidator().validate(email.toString())){
((EditText)myDialog.findViewById(R.id.emailEditText)).setError(getString(R.string.emailWrong));
}
}
if(password.toString().equals("")){
((EditText) myDialog.findViewById(R.id.passwordEditText)).setError(getString(R.string.mandatoryField));
}
if(password_Retyped.toString().equals("")){
((EditText) myDialog.findViewById(R.id.passwordRepEditText)).setError(getString(R.string.mandatoryField));
}
//Check match password
if(!hashPassword.equals(hashPasswordRep)){
((EditText)myDialog.findViewById(R.id.passwordEditText)).setError(getString(R.string.passwordNotMatching));
((EditText)myDialog.findViewById(R.id.passwordRepEditText)).setError(getString(R.string.passwordNotMatching));
}
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
try {
//Start AsyncTask
new loadingBar().execute().get();
Boolean resultOK = ackJSON.has("result");
if(resultOK){
//close dialog
myDialog.dismiss();
// Inflate the Layout
LayoutInflater inflater = getLayoutInflater();
View layout = inflater.inflate(R.layout.custom_toast_success,(ViewGroup) findViewById(R.id.custom_toast_layout_id));
Toast toastOK = new Toast(getApplicationContext());
toastOK.setDuration(Toast.LENGTH_LONG);
toastOK.setView(layout);
toastOK.show();
}else{
//Feedback both using Toasts and textedit
((EditText) myDialog.findViewById(R.id.emailEditText)).setError(getString(R.string.userAlreadyIn));
// Inflate the Layout
LayoutInflater inflater = getLayoutInflater();
View layout = inflater.inflate(R.layout.custom_toast_erroruser,(ViewGroup) findViewById(R.id.custom_toast_no_user));
Toast toastNoUser = new Toast(getApplicationContext());
toastNoUser.setDuration(Toast.LENGTH_SHORT);
toastNoUser.setGravity(Gravity.TOP,0,50);
toastNoUser.setView(layout);
toastNoUser.show();
}
} catch (IOException e) {
// Inflate the Layout
LayoutInflater inflater = getLayoutInflater();
View layout = inflater.inflate(R.layout.custom_toast_errorconnection,(ViewGroup) findViewById(R.id.custom_toast_no_noConn));
Toast toastNoConn = new Toast(getApplicationContext());
toastNoConn.setDuration(Toast.LENGTH_SHORT);
toastNoConn.setGravity(Gravity.TOP,0,50);
toastNoConn.setView(layout);
toastNoConn.show();
} catch (JSONException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
});
}
class loadingBar extends AsyncTask<Void,Integer,JSONObject>{
@Override
protected void onPreExecute() {
super.onPreExecute();
progress.setProgress(0);
progress.show();
}
@Override
protected JSONObject doInBackground(Void... arg0)
{
ackJSON = null;
try
{
for(int i=0;i<2;i++)
{
publishProgress(new Integer[]{i*10});
Thread.sleep(1200);
}
String ack=HTTPRest.putNewUser(name.toString(),surname.toString(),email.toString(),hashPassword);
ackJSON=new JSONObject(ack);
} catch (InterruptedException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return ackJSON;
}
@Override
protected void onProgressUpdate(Integer... values)
{
super.onProgressUpdate(values);
progress.setProgress(values[0].intValue());
}
@Override
protected void onPostExecute(JSONObject result)
{
super.onPostExecute(result);
progress.dismiss();
ackJSON=result;
}
}
如果代码中有任何错误，请告诉我
谢谢
答案 0 :(得分：1)
一切正确，但您将更改此代码
if(name.toString().isEmpty()){
}
因为当您没有输入任何值时，您的代码会出现问题，因此请不要检查您的情况。您的代码只会检查黑色空间。
答案 1 :(得分：1)
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);
new AttemptLogin().execute();
} else {
// Prompt user to enter credentials
Toast.makeText(getApplicationContext(),
"Please enter the credentials!", Toast.LENGTH_LONG)
.show();
}
}
});
class AttemptLogin extends AsyncTask<String, String, String>{
/** * Before starting background thread Show Progress Dialog * */
boolean failure = false;
@Override protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(LoginActivity.this);
pDialog.setMessage("Attempting for login...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@SuppressWarnings("deprecation")
@Override
protected String doInBackground(String... args) {
// TODO Auto-generated method stub
// here Check for success tag
int success;
String username = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
try {
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("username", username));
params.add(new BasicNameValuePair("password", password));
Log.d("request!", "starting");
JSONObject json = jsonParser.makeHttpRequest(AppConfig.URL_LOGIN, "POST", params);
// checking log for json response
//devraj......................
Log.d("Login attempt", json.toString());
// success tag for json
success = json.getInt(TAG_SUCCESS);
if (success == 1){
session.setLogin(true);
Log.d("Successfully Login!", json.toString());
Intent intent = new Intent(LoginActivity.this,Secondpage.class);
startActivity(intent);
return json.getString(TAG_MESSAGE);
}
else{
return json.getString(TAG_MESSAGE);
}
}
catch (JSONException e){
e.printStackTrace();
}
return null;
}
/** * Once the background process is done we need to Dismiss the progress dialog asap * **/
protected void onPostExecute(String message)
{
pDialog.dismiss();
if (message != null){
Toast.makeText(First.this, message, Toast.LENGTH_LONG).show();
}
}
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
答案 2 :(得分：0)
您可以在onPostExecute()方法
Asynctask的生命周期就像这样运行
onPreExecute() -> runs first
doInBackground() -> After onPreExecute
和
`onPostExecute()` -> After doInBackground
因此，您可以在onPostExecute()
答案 3 :(得分：0)
您可以在AsyncTask的onPostExecute方法中进行工作
@Override
protected void onPostExecute(JSONObject result)
{
super.onPostExecute(result);
progress.dismiss();
ackJSON=result;
//do your work here show toast or move to next activity
}
答案 4 :(得分：0)
progress.setCancelable(false);