Animation主要分为两类：一类是渐变动画tweened animation，一类是逐帧动画frame-by-frame animation。渐变动画就是用一帧图片产生四种效果：1、alpha，2、rotate，3、scale，4、translates，可以通过代码或者xml文件两种方法实现。而逐帧动画就是由一系列图片通过快速播放达到动的效果。另外还有一些Animationset、AnimationListener、LayoutAnimationController这些在实例中穿插着讲。
实例一：代码实现tweened animation
①新建一个布局文件：四个Button加一个ImageView
<span style="font-size:14px;"><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
android:id="@+id/imageview"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_marginTop="100dp"
android:src="@drawable/arrow" />
</LinearLayout>
<Button
android:id="@+id/button_alpha"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="@+id/button_rotate"
android:text="Alpha" />
<Button
android:id="@+id/button_rotate"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="@+id/button_scale"
android:text="rotate" />
<Button
android:id="@+id/button_scale"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="@+id/button_translate"
android:text="scale" />
<Button
android:id="@+id/button_translate"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="translate" />
</RelativeLayout></span>②Activity
<span style="font-size:14px;">package com.example.f_animation_tween;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.view.animation.Animation.AnimationListener;
import android.view.animation.AnimationSet;
import android.view.animation.RotateAnimation;
import android.view.animation.ScaleAnimation;
import android.view.animation.TranslateAnimation;
import android.widget.Button;
import android.widget.ImageView;
public class MainActivity extends ActionBarActivity {
private Button button_alpha, button_rotate, button_scale, button_trans;
private ImageView imageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button_alpha = (Button) findViewById(R.id.button_alpha);
button_rotate = (Button) findViewById(R.id.button_rotate);
button_scale = (Button) findViewById(R.id.button_scale);
button_trans = (Button) findViewById(R.id.button_translate);
imageView = (ImageView) findViewById(R.id.imageview);
button_alpha.setOnClickListener(new ButtonAlphaListerner());
button_rotate.setOnClickListener(new ButtonRotateListerner());
button_scale.setOnClickListener(new ButtonScaleListerner());
button_trans.setOnClickListener(new ButtonTransListerner());
}
private class ButtonAlphaListerner implements OnClickListener {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
// 新建一个AlphaAnimation，构造器参数代表从1到0的淡化
AlphaAnimation alphaAnimation = new AlphaAnimation(1, 0);
// 淡化时长为2秒
alphaAnimation.setDuration(2000);
// 重复两次，加一次是三次
alphaAnimation.setRepeatCount(2);
// 设置一个监听器
alphaAnimation.setAnimationListener(new AnimationListener() {
@Override
public void onAnimationStart(Animation arg0) {
// TODO Auto-generated method stub
System.out.println("--->start");
}
@Override
public void onAnimationRepeat(Animation arg0) {
// TODO Auto-generated method stub
System.out.println("--->repeat");
}
@Override
public void onAnimationEnd(Animation arg0) {
// TODO Auto-generated method stub
System.out.println("--->end");
}
});
// 让图片产生淡化动画
imageView.startAnimation(alphaAnimation);
// 也可以让其他控件产生动画
button_alpha.startAnimation(alphaAnimation);
}
}
private class ButtonRotateListerner implements OnClickListener {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
// 旋转动画，围绕的中心点由构造器的得出：
// 第三四个参数代表X轴相对于自身最大，五六个参数Y轴同理，相当于图片的
// 右下角的点，Animation.RELATIVE_TO_PARENT是相对于父控件
RotateAnimation rotateAnimation = new RotateAnimation(0, 360,
Animation.RELATIVE_TO_SELF, 1, Animation.RELATIVE_TO_SELF,
1);
rotateAnimation.setDuration(2000);
imageView.startAnimation(rotateAnimation);
}
}
private class ButtonScaleListerner implements OnClickListener {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
// 横向纵向都缩小为原来的0.1，围绕的点和上面同理
ScaleAnimation scaleAnimation = new ScaleAnimation(1, 0.1f, 1,
0.1f, Animation.RELATIVE_TO_SELF, 1,
Animation.RELATIVE_TO_SELF, 1);
scaleAnimation.setDuration(2000);
// 让其定格在最后
scaleAnimation.setFillAfter(true);
imageView.startAnimation(scaleAnimation);
}
}
private class ButtonTransListerner implements OnClickListener {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
AlphaAnimation alphaAnimation = new AlphaAnimation(1, 0);
TranslateAnimation translateAnimation = new TranslateAnimation(
Animation.RELATIVE_TO_PARENT, 0,
Animation.RELATIVE_TO_PARENT, 1,
Animation.RELATIVE_TO_SELF, 0, Animation.RELATIVE_TO_SELF,
0);
AnimationSet animationSet = new AnimationSet(true);
// 可以通过一个AnimationSet添加多个动画效果，他是Animation的子类
animationSet.addAnimation(translateAnimation);
animationSet.addAnimation(alphaAnimation);
animationSet.setDuration(2000);
imageView.startAnimation(animationSet);
}
}
}
</span>①在res文件夹下新建一个anim文件夹，添加一个alpha.xml文件
<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:interpolator="@android:anim/linear_interpolator" >
<alpha
android:duration="2000"
android:fromAlpha="1.0"
android:toAlpha="0.0" />
</set></span>②Activity主要代码
<span style="font-size:14px;">private class ButtonAlphaListerner implements OnClickListener {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Animation alphaAnimation = AnimationUtils.loadAnimation(
MainActivity.this, R.anim.alpha);
imageView.startAnimation(alphaAnimation);
}
}</span>对于批量修改来说xml的方法是更快的，当然也可以再xml文件中添加几个动画效果，具体的参数需要时就上网查，这里提供一个框架。
实例三：逐帧动画
①在drawable文件夹下放入几张图片然后新建一个anim.xml文件
<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android"
android:oneshot="false" >
<item
android:drawable="@drawable/up"
android:duration="500"/>
<item
android:drawable="@drawable/right"
android:duration="500"/>
<item
android:drawable="@drawable/down"
android:duration="500"/>
<item
android:drawable="@drawable/left"
android:duration="500"/>
a
</animation-list></span>②Activity主要代码
<span style="font-size:14px;">private class ButtonListener implements OnClickListener {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
imageView.setBackgroundResource(R.drawable.anim);
AnimationDrawable animationDrawable = (AnimationDrawable) imageView
.getBackground(); //AnimationDrawable类就是用于实现逐帧动画
isStart = !isStart;
if (isStart)
animationDrawable.start();
else
animationDrawable.stop();
}
}</span>A layout animation controller is used to animated a layout‘s, or a view group‘s, children. Each child uses the same animation but for every one of them, the animation starts at a different time.
ListView也是继承ViewGroup的，所以以它为例写一个Demo。
①布局文件
<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="@+id/listview"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
<Button
android:id="@+id/button"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="test" />
</LinearLayout></span>
②res文件夹下新建一个anim文件夹，新建anim.xml和anim_layout.xml两个文件
<span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" >
<alpha
android:duration="1000"
android:fromAlpha="0"
android:toAlpha="1" />
</set></span><span style="font-size:14px;"><?xml version="1.0" encoding="utf-8"?>
<layoutAnimation xmlns:android="http://schemas.android.com/apk/res/android"
android:animation="@anim/anim"
android:animationOrder="random"
android:delay="200%" />
</span>以上xml设置动画效果，执行顺序，和间隔时间
③Activity
package com.example.f_animation_layoutcon;
import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.LayoutAnimationController;
import android.widget.Adapter;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
public class MainActivity extends ActionBarActivity {
private Button button;
private ListView listView;
private ArrayAdapter<String> adapter;
private List<String> list;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button = (Button) findViewById(R.id.button);
listView = (ListView) findViewById(R.id.listview);
list = new ArrayList<String>();
list.add("北京");
list.add("上海");
list.add("广州");
adapter = new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_list_item_1, list);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Animation animation = AnimationUtils.loadAnimation(
MainActivity.this, R.anim.anim);
LayoutAnimationController lac = new LayoutAnimationController(
animation);
lac.setOrder(LayoutAnimationController.ORDER_RANDOM);
lac.setDelay(1.0f);
listView.setLayoutAnimation(lac);
listView.setAdapter(adapter);
// 也可以直接在listview里面指定layoutAnimation
// 在ListView中添加属性android:layoutAnimation="@anim/anim_layout"
}
});
}
}
执行效果，点击Button后，ListView的项目一个一个显示，而不是一下就全部显示。
小结：1、tween animation的两种实现方式、XML对批量修改更有用，事件监听器。2、frame-by-frame animation。3、LayoutAnimationController也是有两种实现方式。
原文地址：http://blog.csdn.net/leelit/article/details/39666721
