[6] Intent, Handler, Exit

1. Intent

Sample Source

package com.ssh.user.ex_1206; import android.content.Intent; import android.net.Uri; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; public class IntentMainActivity extends AppCompatActivity { Button btn_next, btn_link; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_intent_main); btn_next = (Button)findViewById(R.id.btn_next); // activity 이동 btn_link = (Button)findViewById(R.id.btn_link); // web_link btn_link.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { //웹 페이지로 화면 전환하기. //안드로이드 화면 전환 기능을 담당하는 Intent클래스 Intent i = new Intent( Intent.ACTION_VIEW ); i.setData(Uri.parse("http://www.naver.com")); startActivity(i); // Intent의 정보를 가지고 화면 전환 } }); btn_next.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { // 1. 생성하면서 바로 설정 // Intent i = new Intent(IntentMainActivity.this, IntentSubActivity.class); // 2. 나중에 설정 Intent i = new Intent(); // 이동하고자 하는 activity를 명시한다. // 단, 이동하고자 하는 클래스는 Manifest에 등록되어 있어야 한다. i.setClass(IntentMainActivity.this, IntentSubActivity.class); startActivity(i); // 화면전환 } }); }//onCreate() }

<?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:id="@+id/activity_intent_main" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context="com.ssh.user.ex_1206.IntentMainActivity" android:orientation="vertical"> <Button android:id="@+id/btn_next" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="next" /> <Button android:id="@+id/btn_link" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="web"/> </LinearLayout>

package com.ssh.user.ex_1206; import android.content.Intent; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; public class IntentSubActivity extends AppCompatActivity { Button btn_pre; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_intent_sub); btn_pre = (Button)findViewById(R.id.btn_pre); btn_pre.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent i = new Intent(IntentSubActivity.this, IntentMainActivity.class); //intent에게 중복 호출 방지를 위한 Flag 적용(현재창 닫기|맨위중복 방지) i.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP); startActivity(i); } }); } }

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_intent_sub" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context="com.ssh.user.ex_1206.IntentSubActivity"> <Button android:id="@+id/btn_pre" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="previous"/> </RelativeLayout>

2. Handler

Sample Source

package com.ssh.user.ex_1206; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; import android.widget.TextView; public class HandlerActivity extends AppCompatActivity { TextView txt_count; Button btn_start, btn_stop; int count; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_handler); txt_count = (TextView)findViewById(R.id.txt_count); btn_start = (Button)findViewById(R.id.btn_start); btn_stop = (Button)findViewById(R.id.btn_stop); btn_start.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { //핸들러 호출(java의 Thread와 비슷) handler.sendEmptyMessage(0); } }); btn_stop.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { //핸들러 정지 handler.removeMessages(0); } }); }//onCreate //핸들러 Handler handler = new Handler() { @Override public void handleMessage(Message msg) { // 1000 ms 이후 자신을 호출 handler.sendEmptyMessageDelayed(0,1000); count++; txt_count.setText(""+count); } }; }

<?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:id="@+id/activity_handler" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context="com.ssh.user.ex_1206.HandlerActivity" android:orientation="vertical"> <TextView android:id="@+id/txt_count" android:layout_width="match_parent" android:layout_height="match_parent" android:text="0" android:textSize="30dp" android:layout_weight="1" android:gravity="center" /> <Button android:id="@+id/btn_start" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="start"/> <Button android:id="@+id/btn_stop" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="stop"/> </LinearLayout>

3. Exit

Sample Source

package com.ssh.user.ex_1206; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.v7.app.AppCompatActivity; import android.widget.Toast; public class ExitActivity extends AppCompatActivity { int timeCount = 0; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_exit); } @Override public void onBackPressed() { if(timeCount == 0) { handler.sendEmptyMessage(0); Toast.makeText(getApplicationContext(), "한번더 누르시면 종료됩니다.", Toast.LENGTH_SHORT).show(); } else finish(); } Handler handler = new Handler() { @Override public void handleMessage(Message msg) { handler.sendEmptyMessageDelayed(0, 1000); timeCount++; if(timeCount >= 3) { timeCount = 0; handler.removeMessages(0); } } }; }