[Android] 動畫按鈕(animation button)

今天來實作一個可以放大縮小的動畫按鈕
1.首先先加入一個imagebutton，我們找一張並命名為fba.png
2.要加入二個xml檔，一個負責放大（to_large.xml)，另一個負責縮小（to_small.xml)

 res/anim/to_large.xml

<scale xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/decelerate_interpolator"
    android:fromXScale="1.0" android:toXScale="2.0" android:fromYScale="1.0"
    android:toYScale="2.0" android:pivotX="50%" android:pivotY="50%"
    android:duration="500" />

<!-- android:fromXScale = "1.0" //fromXScale表示從什麼大小開始放大,1.0表示從原本圖的大小開始放大,
0.5則是初始值是原圖縮小一倍 -->
<!-- android:toXScale="2.0"  //toXScale表示放大到多大,2.0表示放大到原圖的2倍 -->

res/anim/to_small.xml

<scale xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/accelerate_interpolator"
    android:fromXScale="2.0" android:toXScale="1.0" android:fromYScale="2.0"
    android:toYScale="1.0" android:pivotX="50%" android:pivotY="50%"
    android:duration="500" />

MainActivity.java

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.Animation.AnimationListener;
import android.widget.ImageButton;

public class MainActivity extends Activity implements AnimationListener {
 private Animation toLargeAnimation;
 private Animation toSmallAnimation;
 private ImageButton imageView;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  imageView = (ImageButton) findViewById(R.id.imageView);

  toLargeAnimation = AnimationUtils.loadAnimation(MainActivity.this,
    R.anim.to_large);
  toSmallAnimation = AnimationUtils.loadAnimation(MainActivity.this,
    R.anim.to_small);
  toLargeAnimation.setAnimationListener(MainActivity.this);
  toSmallAnimation.setAnimationListener(MainActivity.this);
  imageView.startAnimation(toSmallAnimation);

  addListenerOnButton();
 }

 public void onAnimationStart(Animation animation) {
  // TODO Auto-generated method stub

 }

 public void onAnimationEnd(Animation animation) {

  if (animation.hashCode() == toLargeAnimation.hashCode())
   imageView.startAnimation(toSmallAnimation);
  else
   imageView.startAnimation(toLargeAnimation);

 }

 public void onAnimationRepeat(Animation animation) {
  // TODO Auto-generated method stub

 }

 public void addListenerOnButton() {

  imageView.setOnClickListener(new OnClickListener() {

   public void onClick(View arg0) {
    // 按下按鈕要做的事,就寫在這裡

   }

  });

 }
}

res/layout/activity_main.xml

<RelativeLayout 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"
    tools:context=".MainActivity" >

    <ImageButton
        android:id="@+id/imageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:layout_marginBottom="20dp"
        android:background = "#ffffff"
        android:src="@drawable/fba" />

</RelativeLayout>

參考連結
http://www.360doc.com/content/11/1208/16/8157240_170676944.shtml
http://www.pocketdigi.com/20110511/277.html