[Android Studio][Kotlin] - Intent 로 화면(Activity)간 값 전달하기

 

 

 

[보내는 activity]

val intent = Intent(this, SubActivity :: class.java)

 

(원하는 이름의 key 값)

intent.putExtra("msg", 보낼 값)

 

 

MainActivity.kt

package com.example.myapplication

import android.content.Intent
import android.os.Bundle
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import com.example.myapplication.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {
    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        val view = binding.root
        setContentView(view)

        Toast.makeText(this, binding.tvSendMsg.text, Toast.LENGTH_SHORT).show( )

        binding.btnSub.setOnClickListener{
            val intent = Intent(this,SubActivity::class.java)
            intent.putExtra("msg",binding.tvSendMsg.text.toString())
            startActivity(intent)
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">


    <TimePicker
        android:id="@+id/tp_timepicker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:timePickerMode="spinner"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/btn_del"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"

        android:text="해지"
        app:layout_constraintBaseline_toBaselineOf="@+id/btn_reg"
        app:layout_constraintEnd_toStartOf="@+id/btn_reg"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/tp_timepicker" />

    <Button
        android:id="@+id/btn_reg"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="28dp"

        android:text="등록"

        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/btn_del"
        app:layout_constraintTop_toBottomOf="@+id/tp_timepicker" />

    <Button
        android:id="@+id/btn_sub"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="과학적 수면시간"
        app:layout_constraintBottom_toTopOf="@+id/tp_timepicker"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/tv_sendMsg"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="내가 보낼 메세지"
        android:textSize="24sp"
        app:layout_constraintBottom_toTopOf="@+id/btn_sub"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />


</androidx.constraintlayout.widget.ConstraintLayout>

 

[받는 activity]

 

SubActivity.kt

package com.example.myapplication

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import com.example.myapplication.databinding.ActivitySubBinding

class SubActivity : AppCompatActivity() {
    lateinit var binding: ActivitySubBinding
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivitySubBinding.inflate(layoutInflater)
        val view = binding.root
        setContentView(view)

        if (intent.hasExtra("msg")) {
            binding.tvGetMsg.text = intent.getStringExtra("msg")
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".SubActivity">

    <TextView
        android:id="@+id/tv_getMsg"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="지금이게"
        android:textSize="48sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>