버튼을 press 할때 배경색 바꾸기

<?xml version="1.0" encoding="utf-8"?>

<resources>

    <color name="color_red">#FF0000</color>

    

</resources>

<?xml version="1.0" encoding="utf-8"?>

<resources>

    <drawable name="red_bg">#FF0000</drawable>

    <drawable name="green_bg">#00FF00</drawable>

    

</resources>

<?xml version="1.0" encoding="utf-8"?>

<selector xmlns:android="http://schemas.android.com/apk/res/android" >

    <item android:state_pressed="true"

        android:drawable="@drawable/red_bg"/>

    

    <item android:drawable="@drawable/green_bg"></item>

    

</selector>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:id="@+id/LinearLayout1"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    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=".MainActivity" >

    <Button

        android:id="@+id/button13"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_marginTop="33dp"

        android:background="@drawable/button_bg"

        android:text="@string/button" />

    <ImageView

        android:id="@+id/imageView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:src="@drawable/rotate_image" />

    <TextView

        android:id="@+id/textView1"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="message" />

</LinearLayout>

package com.wooriworld.Assign_Cal;

import android.R.integer;

import android.R.interpolator;

import android.os.Bundle;

import android.app.Activity;

import android.content.DialogInterface;

import android.graphics.drawable.Drawable;

import android.graphics.drawable.RotateDrawable;

import android.view.View.OnClickListener;

import android.view.Menu;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ImageView;

public class MainActivity extends Activity {

RotateDrawable mDrawable;//로테이트 드로블 정의 

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

   

        

        //이미지 로테이트 예제 

        ImageView imageView = (ImageView)findViewById(R.id.imageView1);

        mDrawable = (RotateDrawable)imageView.getDrawable();

        Button btn13=(Button)findViewById(R.id.button13);

        btn13.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

int level = mDrawable.getLevel();

level=(level+1000)%10000;

mDrawable.setLevel(level);

}

} );

        //칼라값과 스트링 가져오기 

        //칼라값은 int 로 받음 

        int myColor = getResources().getColor(R.color.color_red);

         String mymessage = getResources().getString(R.string.my_message);

         String[] myArray = getResources().getStringArray(R.array.myArray);

        

         Drawable mypicture = getResources().getDrawable(R.drawable.love);

        

    }

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.

        getMenuInflater().inflate(R.menu.main, menu);

        return true;

    }

    //

    

}