[Kotlin] DataBinding + LiveData

build.gradle (Module: app)

android {
    dataBinding {
    	enabled = true
    }
}

 

 

 

 

 

 

 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout>
    <data>
        <variable
            name="mainActivity"
            type="com.jwsoft.kotlinproject.MainActivity" />
    </data>

    <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:gravity="center"
        android:background="#FFBB11"
        tools:context=".MainActivity">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@{mainActivity.liveName}"
            android:hint="James Kim"
            android:textSize="30dp"
            android:textStyle="bold" />

        <Button
            android:id="@+id/btnLong"
            android:layout_width="250dp"
            android:layout_height="wrap_content"
            android:text="혀가 긴 개발자"
            android:textSize="20dp"
            android:textStyle="bold"
            android:layout_marginTop="30dp"/>

        <Button
            android:id="@+id/btnShort"
            android:layout_width="250dp"
            android:layout_height="wrap_content"
            android:text="혀가 길지 않은 개발자"
            android:textSize="20dp"
            android:textStyle="bold" />

    </LinearLayout>

</layout>

activity_main.xml

 

 

 

 

 

 

 

MainActivity.kt

package com.jwsoft.kotlinproject

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.databinding.DataBindingUtil
import androidx.lifecycle.MutableLiveData
import com.jwsoft.kotlinproject.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding
    val liveName: MutableLiveData<String> = MutableLiveData()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = DataBindingUtil.setContentView(this, R.layout.activity_main)
        binding.apply {
            mainActivity = this@MainActivity
            lifecycleOwner = this@MainActivity

            btnLong.setOnClickListener { liveName.value = "혀가 긴 개발자" }
            btnShort.setOnClickListener { liveName.value = "혀가 길지 않은 개발자" }
        }
    }

}

실행 결과