ScaleAnimation缩放动画Demo

一、通过Java实现动画：

fromX ：Horizontal scaling factor to apply at the start of the animation

toX： Horizontal scaling factor to apply at the end of the animation

fromY： Vertical scaling factor to apply at the start of the animation

toY ：Vertical scaling factor to apply at the end of the animation

pivotX ：The X coordinate of the point about which the object is being scaled, specified as an absolute number where 0 is the left edge. (This point remains fixed while the object changes size.)

pivotY :The Y coordinate of the point about which the object is being scaled, specified as an absolute number where 0 is the top edge. (This point remains fixed while the object changes size.)

package com.jikexueyuan.scaleanimation;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.ScaleAnimation;

public class MainActivity extends Activity {
	
	
	private ScaleAnimation sa;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        
        sa = new ScaleAnimation(0, //<strong>fromX</strong> 

1, //<span style="font-weight: bold;">toX</span>

0, //<span style="font-weight: bold;">fromY</span>

1,//<span style="font-weight: bold;">toY</span>

100,  //<strong>pivotX</strong> 

50  //<span style="font-weight: bold;">pivotY</span>

);
        sa = new ScaleAnimation(0, 1, 0, 1, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);
        sa.setDuration(1000);
        
        findViewById(R.id.btnScaleMe).setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				arg0.startAnimation(sa);
//				arg0.startAnimation(AnimationUtils.loadAnimation(MainActivity.this, R.anim.sa));
			}
		});
    }
}

二、通过sa.xml实现动画：

package com.jikexueyuan.scaleanimation;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.ScaleAnimation;

public class MainActivity extends Activity {
	
	
	private ScaleAnimation sa;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        
//        sa = new ScaleAnimation(0, 1, 0, 1,100,50);
//        sa = new ScaleAnimation(0, 1, 0, 1, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);
//        sa.setDuration(1000);
        
        findViewById(R.id.btnScaleMe).setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				arg0.startAnimation(AnimationUtils.loadAnimation(MainActivity.this, R.anim.sa));
			}
		});
    }
    }
}

sa.xml：

<?xml version="1.0" encoding="utf-8"?>
<scale xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromXScale="0"
    android:toXScale="1"
    android:fromYScale="0"
    android:toYScale="1"
    android:duration="1000"
    android:pivotX="50%"
    android:pivotY="50%" >

</scale>