[Kotlin] Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK

Intent.FLAG_ACTIVITY_NEW_TASK  or  Intent.FLAG_ACTIVITY_CLEAR_TASK

---

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<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"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="1 페이지"
        android:textSize="30dp" />

    <Button
        android:id="@+id/btnMain"
        android:layout_width="220dp"
        android:layout_height="80dp"
        android:text="다음 페이지로 이동"
        android:textSize="22dp"
        android:layout_marginTop="100dp"/>

</LinearLayout>

activity_main.xml

 

 

 

 

 

activity_sub.xml

<?xml version="1.0" encoding="utf-8"?>
<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"
    tools:context=".SubActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="2 페이지"
        android:textSize="30dp" />

    <Button
        android:id="@+id/btnSub"
        android:layout_width="220dp"
        android:layout_height="80dp"
        android:text="처음으로 이동"
        android:textSize="22dp"
        android:layout_marginTop="100dp"/>

</LinearLayout>

activity_sub.xml

 

 

 

 

 

SubActivity.kt

package com.jwsoft.kotlinproject

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        btnMain.setOnClickListener {
            val intent = Intent(this, SubActivity::class.java)
            startActivity(intent)
        }
    }

}

 

 

 

 

 

 

 

MainActivity.kt

package com.jwsoft.kotlinproject

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        btnMain.setOnClickListener {
            val intent = Intent(this, SubActivity::class.java)
            startActivity(intent)
        }
    }

}

activity가 스택처럼 쌓인다.

 

실행 결과

 

 

 

 

 

---

SubActivity.kt

package com.jwsoft.kotlinproject

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_sub.*

class SubActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_sub)

        btnSub.setOnClickListener {
            val intent = Intent(this, MainActivity::class.java)
            intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
            startActivity(intent)
        }
    }

}

SubActivity.kt 에만

intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK 추가

 

실행 결과

 

 

 

 

---

MainActivity.kt

package com.jwsoft.kotlinproject

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_sub.*

class SubActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_sub)

        btnSub.setOnClickListener {
            val intent = Intent(this, MainActivity::class.java)
            intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
            startActivity(intent)
        }
    }

}

MainActivity.kt 에도

intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK 추가

 

실행 결과