MVVM简单实现

MVVM模式跟之前的MVC或者MVP不一样 它是在布局的时候有很大区别

main布局

<?xml version="1.0" encoding="utf-8"?>
<layout
    xmlns:android="http://schemas.android.com/apk/res/android"
  >

    <data>

        <variable
            name="user"
            type="demo04.com.mvvmstuday.User"/>
    </data>
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <TextView
            android:text="@{user.username}"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:text="@{user.nickname}"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:text="@{String.valueOf(user.age)}"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </LinearLayout>

</layout>

MainActivity

import android.databinding.DataBindingUtil;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import demo04.com.mvvmstuday.databinding.ActivityMainBinding;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ActivityMainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_main);
        User user = new User();
        user.setAge(34);
        user.setUsername("zhangsan");
        user.setNickname("张三");
        binding.setUser(user);

    }
}

User类

public class User {
    private String username;
    private String nickname;
    private int age;

    public User() {
    }

    public User(String username, String nickname, int age) {
        this.username = username;
        this.nickname = nickname;
        this.age = age;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getNickname() {
        return nickname;
    }

    public void setNickname(String nickname) {
        this.nickname = nickname;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

这只是简单的实现赋值的小demo   如果想更深入的了解，还请去官网上查询