model继承BaseObservable,
如果是 public 修饰符,则可以直接在成员变量上方加上 @Bindable
如果是private修饰符,则应该在get方法上方加上 @Bindable
在set方法里的最后加上notifyChange();刷新数据
model代码如下:
package com.example.myapplication10;
import androidx.databinding.BaseObservable;
import androidx.databinding.Bindable;
public class User extends BaseObservable {
private String name;
private int age;
public User(String name, int age) {
this.name = name;
this.age = age;
}
@Bindable
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
notifyChange();
}
@Bindable
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
notifyChange();
}
}
如何绑定点击事件?如下:
package com.example.myapplication10;
import androidx.appcompat.app.AppCompatActivity;
import androidx.databinding.DataBindingUtil;
import android.os.Bundle;
import com.example.myapplication10.databinding.ActivityMainBinding;
public class MainActivity extends AppCompatActivity {
private User user;
private GoodsHandler goodsHandler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ActivityMainBinding activityMainBinding = DataBindingUtil.setContentView(this, R.layout.activity_main);
user = new User("张三",50);
activityMainBinding.setUser(user);
activityMainBinding.setGoodsHandler(new GoodsHandler());
}
public class GoodsHandler {
//事件处理函数
public void changeName() {
user.setName("哈哈哈");
}
//事件处理函数
public void changeAge() {
user.setAge(33);
}
}
}
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="user"
type="com.example.myapplication10.User" />
<variable
name="goodsHandler"
type="com.example.myapplication10.MainActivity.GoodsHandler" />
</data>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="@{()->goodsHandler.changeName()}"
android:textSize="25dp"
android:text="@{user.name}"></TextView>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="@{()->goodsHandler.changeAge()}"
android:textSize="25dp"
android:layout_marginTop="50dp"
android:text="@{String.valueOf(user.age)}">
</TextView>
</RelativeLayout>
</layout>
注意,非字符串类型的字段,字段绑定应该转换成字符串,像这样写:
android:text="@{String.valueOf(user.age)}"