基于kotlin的，DataBinding+Recycleview,并实现item的子控件的点击事件

基于kotlin的，DataBinding+Recycleview,并实现item的子控件的点击事件

核心代码如下：Activity

class MainActivity : AppCompatActivity() {
    val studentInfo: Student? = null
    lateinit var binding: ActivityMainBinding
    lateinit var recyclerView: RecyclerView
    var users: MutableList<User> = mutableListOf()
    lateinit var user: User
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = DataBindingUtil.setContentView(this, R.layout.activity_main)
//        binding.user = User("Test","User")
//        val binding: ActivityMainBinding = ActivityMainBinding.inflate(getLayoutInflater())
        val studentInfo = Student()
        studentInfo.name.set("我叫朝阳杨大爷")
        studentInfo.age.set(20)
        binding.studentInfo = studentInfo
        binding.eventListener = EventListener()
        recyclerView = binding.rvContent
        recyclerView.layoutManager = LinearLayoutManager(this)

        for (i in 0 until 30) {
            user = User(null,null)
            user.firstName = "我是$i"
            user.lastName = "他是$i"
            users.add(user)
//            User("我是$i", "他是$i")
        }
        val adapter = users?.let { FruitAdapter(it, BR.user) }
        recyclerView.adapter = adapter
//        binding.setClick { toast("点击了我") }
//        binding.tvStudenname.setOnClickListener { studentInfo.name.set("我还是叫叫朝阳杨大爷") }
//        binding.tvAge.setOnClickListener {  studentInfo.age.set(18)}
//        val map = ObservableArrayMap<String, Any>()
//        map["name"]= "我叫杨大爷"
//        map["age"] = 20
//        binding.studentInfo = map


    }

    inner class EventListener {

        fun onClick(view: View) {
            binding.studentInfo!!.name.set("我叫不是你大爷")
            binding.studentInfo!!.age.set(200)
//            studentInfo.age.set(200)
            Toast.makeText(this@MainActivity, "点击了并刷新worker对象的值", Toast.LENGTH_LONG).show()
        }

        fun btnClick(view: View) {
            view.id
            Toast.makeText(this@MainActivity, "监听器方式", Toast.LENGTH_LONG).show()
        }
//         fun onTextChanged(charSequence :CharSequence ,  i:Int, i1:Int , i2:Int ){
//             binding.studentInfo!!.age.set(300)
//
//         }

        fun onLongClick(view: View): Boolean {
            Toast.makeText(this@MainActivity, "长按了", Toast.LENGTH_LONG).show()
            return false
        }
    }

}

Adapter:

class FruitAdapter (itemList: List<User>, brId: Int) : BaseAdapter<User, FruitItemBinding>(itemList, brId) {
    var onItemClickListener: AdapterView.OnItemClickListener? = null

    override fun getLayoutId(): Int {
        return R.layout.fruit_item //item对应的layoutId
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        super.onBindViewHolder(holder, position)
        holder.binding.tvAges.setOnClickListener { mContext!!.toast("我被点了,我是第${position}个") }

    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        return super.onCreateViewHolder(parent, viewType)

    }

}

BaseAdapter:

//两个泛型，T代表item的model类型即itemList的bean类型，TBinding代表itemLayout对应生成的XXXBinding类，比如itemLayout是fruit_item.xml，对应的就是FruitItemBinding
//两个参数itemList对应具体要显示的arrayList，brId则对应itemLayout里相应variable的变量名，比如variable的name是fruit，brId就是BR.fruit
abstract class BaseAdapter<T, TBinding: ViewDataBinding>(private val itemList: List<T>,
                                                         private val brId: Int) : RecyclerView.Adapter<BaseAdapter<T, TBinding>.ViewHolder>() {

    protected var mContext: Context? = null

    inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {//相当于itemView
        lateinit var binding: TBinding
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        if (mContext == null) {
            mContext = parent.context
        }
        //因为TBinding的具体类型不确定，这里只能用DataBindingUtil.inflate()，而不能用XXXBinding.inflate()
        val binding: TBinding = DataBindingUtil.inflate(LayoutInflater.from(mContext), getLayoutId(), parent, false)
        val holder = ViewHolder(binding.root)
        holder.binding = binding
        return holder
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        holder.binding.setVariable(brId, itemList[position])
        //立即执行绑定，在对view变化时效敏感的地方常用，不加这句有可能出现itemView更新滞后、闪烁等问题
        holder.binding.executePendingBindings()
    }

    override fun getItemCount(): Int {
        return itemList.size
    }
    //获取具体子adapter对应的itemLayoutId
    abstract fun getLayoutId(): Int

}

Activity对象的Xml：

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>
        <!--<variable name="user" type="com.ypf.databindingtest.bean.User"/>-->
        <!--<variable name="handlers" type="com.ypf.databindingtest.MyHandlers"/>-->
        <import type="com.ypf.databindingtest.bean.Student"/>
        <!--<import type="androidx.databinding.ObservableArrayMap"/>-->
        <!--<variable name="studentInfo" type="ObservableArrayMap&lt;String, Object&gt;"/>-->
        <variable name="studentInfo"
                  type="Student"/>
        <!--<variable-->
        <!--name="click"-->
        <!--type="android.view.View.OnClickListener"/>-->
        <variable name="eventListener" type="com.ypf.databindingtest.MainActivity.EventListener"/>
    </data>
    <LinearLayout
            android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="match_parent">
        <Button
                android:id="@+id/tv_studenname"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:textSize="20sp"
                android:onClick="@{(view)->eventListener.btnClick(view)}"
                android:text="@{studentInfo.name}"/>
        <TextView android:id="@+id/tv_age"
                  android:layout_gravity="center"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content"
                  android:textSize="20sp"
                  android:onClick="@{eventListener.onClick}"
                  android:text="@{String.valueOf(studentInfo.age)}"
        />

        <EditText android:id="@+id/tv_age1"
                  android:layout_gravity="center"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content"
                  android:textSize="20sp"
                  android:text="@{String.valueOf(studentInfo.age)}"
        />

        <androidx.recyclerview.widget.RecyclerView
                android:id="@+id/rv_content"
                android:layout_width="match_parent"
                android:layout_height="wrap_content">

        </androidx.recyclerview.widget.RecyclerView>
    </LinearLayout>
</layout>

Adapter对应的xml：

<?xml version="1.0" encoding="utf-8"?>
<layout>
    <data>
<variable name="user" type="com.ypf.databindingtest.bean.User"/>
    </data>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="wrap_content">
    <TextView android:id="@+id/tv_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
              android:text="@{user.firstName}"
    />
    <TextView
            android:id="@+id/tv_ages"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@{user.lastName}"
    />


</LinearLayout>

</layout>

源码如下：

https://download.csdn.net/download/u013075460/12484252