DataBinding

 <?xml version="1.0" encoding="utf-8"?>
 <layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>
        <variable name="user" type="com.example.cunli.databing.web.User"/>

    </data>
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <EditText android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@={user.email}"
            android:id="@+id/email"
            />
        <TextView android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@={user.password}"
            android:id="@+id/password"
            android:layout_marginTop="10dp"/>

        <Button
            android:layout_marginTop="30dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/btn"
            android:onClick="hello"
            android:text="@string/app_name"/>

    </LinearLayout>
 </layout>

 package com.example.cunli.databing.web;

 import android.databinding.BaseObservable;
 import android.databinding.Bindable;

 import com.example.cunli.databing.BR;

 /**
 * Created by winder on 2016/7/6.
 */
 public class User extends BaseObservable {
    public  String email;
    public  String password;

    public User() {
    }

    public User(String email, String password) {
        this.email = email;
        this.password = password;
    }

    @Bindable
    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
        notifyPropertyChanged(BR.password);
    }

    @Bindable
    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
        notifyPropertyChanged(BR.email);
    }

 }

 package com.example.cunli.databing.activity;

 import android.databinding.DataBindingUtil;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
 import android.util.Log;
 import android.view.View;
 import android.widget.Toast;

 import com.example.cunli.databing.R;
 import com.example.cunli.databing.databinding.ActivityMainBinding;
 import com.example.cunli.databing.server.TeachLogServer;
 import com.example.cunli.databing.web.CheckTeachLog;
 import com.example.cunli.databing.web.TeachLog;
 import com.example.cunli.databing.web.User;

 public class MainActivity extends AppCompatActivity {

    private TeachLogServer teachLogServer = new TeachLogServer();
    User user;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        ActivityMainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_main);

        user = new User("haliluya", "thankyoulord");
        binding.setUser(user);

    }

    public void hello(View view){

        Log.e("password","------getEmail------- "+user.getEmail());

        Toast.makeText(this,user.getEmail()+"\t"+user.getPassword(), Toast.LENGTH_SHORT).show();
    }

 }