I can't understand why my java bean properties it's not updated after the user has changed the text in some textfield. I have configured the pojo and binding but it's not working. Can someone explain me why is not working? The binding is working just in the beggining if i initialized the bean in onCreate method using setter. But changes are not merged in the user bean when Im calling onSignup method.
activity_registration.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable name="user" type="main.client.android.musichall.registration.model.User" />
</data>
<android.support.constraint.ConstraintLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="@dimen/activity_horizontal_margin"
tools:context="main.client.android.musichall.registration.RegistrationActivity">
<Spinner
android:id="@+id/spinner"
android:layout_width="368dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:listitem="@array/activity_registration_modes" />
<TextView
android:id="@+id/activity_registration_text_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
app:layout_constraintTop_toBottomOf="@+id/spinner"
tools:layout_editor_absoluteX="8dp"
android:text="@string/activity_registration_text_name" />
<EditText
android:id="@+id/activity_registration_text_field_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintTop_toBottomOf="@+id/activity_registration_text_name"
tools:layout_editor_absoluteX="8dp"
android:text="@{user.name}"/>
<TextView
android:id="@+id/activity_registration_text_email"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="@string/activity_registration_text_email"
app:layout_constraintTop_toBottomOf="@+id/activity_registration_text_field_name"
tools:layout_editor_absoluteX="8dp" />
<EditText
android:id="@+id/activity_registration_text_field_email"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="12dp"
android:ems="10"
android:inputType="textEmailAddress"
app:layout_constraintTop_toBottomOf="@+id/activity_registration_text_email"
tools:layout_editor_absoluteX="8dp"
android:text="@{user.email}"/>
<TextView
android:id="@+id/activity_registration_text_password"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="@string/activity_registration_text_password"
app:layout_constraintTop_toBottomOf="@+id/activity_registration_text_field_email"
tools:layout_editor_absoluteX="8dp" />
<EditText
android:id="@+id/activity_registration_text_field_password"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:ems="10"
android:inputType="textPassword"
android:text="@{user.password}"
app:layout_constraintTop_toBottomOf="@+id/activity_registration_text_password"
tools:layout_editor_absoluteX="8dp" />
<Button
android:id="@+id/activity_registration_button_sign_up"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:text="@string/sign_up"
android:onClick="onSignUpClick"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent" />
</android.support.constraint.ConstraintLayout>
</layout>
RegistrationActivity.java
package main.client.android.musichall.registration;
import android.content.Intent;
import android.databinding.DataBindingUtil;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import main.client.android.musichall.R;
import main.client.android.musichall.databinding.ActivityRegistrationBinding;
import main.client.android.musichall.login.LoginActivity;
import main.client.android.musichall.registration.model.User;
public class RegistrationActivity extends AppCompatActivity {
private static RegistrationPresenter presenter;
private ActivityRegistrationBinding binding;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_registration);
presenter = new RegistrationPresenter(this);
binding = DataBindingUtil.setContentView(this, R.layout.activity_registration);
User user = new User();
binding.setUser(user);
}
public void onSignUpClick (View view) {
User user = binding.getUser();
user.getEmail();
presenter.onSignUpClick(user);
}
public void onSignUpDone(User user) {
startActivity(new Intent(this, LoginActivity.class));
}
}
User.class
package main.client.android.musichall.registration.model;
import android.databinding.BaseObservable;
import android.databinding.Bindable;
import main.client.android.musichall.BR;
/**
* Created by sangra on 02/12/17.
*/
public class User extends BaseObservable{
private String name;
private String username;
private String email;
private String password;
@Bindable
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
notifyPropertyChanged(BR.name);
}
@Bindable
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
notifyPropertyChanged(BR.username);
}
@Bindable
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
notifyPropertyChanged(BR.email);
}
@Bindable
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
notifyPropertyChanged(BR.password);
}
}
It appears that you are not implementing two-way data binding. So at the moment your views will only display what is in your User object and will not change it's values.
To implement two-way data binding you need to change the following:
android:text="@{user.password}" to android:text="@={user.password}"
Please note the = after @ when binding to user.password
When text is now entered into your EditText the corresponding field in User should be updated.
Hope this helps.
Source: https://www.bignerdranch.com/blog/two-way-data-binding-on-android-observing-your-view-with-xml