<Android 基础(二十五)> Frame Animation
简介
Frame Animation, 逐帧动画,通过定义一系列的Drawable对象来实现动画效果,可以用来作为视图的背景。
Frame Animation在代码中体现为AnimationDrawable对象,可以通过xml文件快创建,放在在/res/drawable/目录下,设置为视图背景后,调用start()方法即可执行逐帧动画。
XML文件
Tags:
< animation-list > 作为父节点,代表Animation Drawable
< item >作为子节点,代表逐帧动画内容,一张一张图片
Attributes:
属性 | 含义 |
---|---|
android:oneshot=”false | true” |
android:variablePadding=”false | true” |
android:visible=”false | true” |
android:drawable=”@drawable/xxxxx” | item图片资源 |
android:duration=”xxxxx” | drawable播放时间,单位ms |
Res:
/res/drawable/{folder}
<?xml version="1.0" encoding="utf-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/selected"
android:oneshot="true"
android:variablePadding="false"
android:visible="true">
<item android:drawable="@drawable/ic_action_add" android:duration="500"/>
<item android:drawable="@drawable/ic_action_anchor" android:duration="500"/>
<item android:drawable="@drawable/ic_action_alarm" android:duration="500"/>
<item android:drawable="@drawable/ic_action_amazon" android:duration="500"/>
<item android:drawable="@drawable/ic_action_ac" android:duration="500"/>
</animation-list>
Coding
使用XML资源
imageView.setBackgroundResource(R.drawable.frame_anim);//设置背景
Drawable bgDrawable = imageView.getBackground();//获取背景
if(bgDrawable instanceof AnimationDrawable) {
((AnimationDrawable) bgDrawable).start();//如果为AnimationDrawable则执行动画
}
纯代码实现
***
imageView.setBackground(createAnimationDrawable());//设置背景
Drawable bg = imageView.getBackground();
if(bg instanceof AnimationDrawable) {
((AnimationDrawable) bg).start();//开始动画
}
***
private AnimationDrawable createAnimationDrawable() {
AnimationDrawable animationDrawable = new AnimationDrawable();
animationDrawable.addFrame(getResources().getDrawable(R.drawable.ic_action_add), 500);
animationDrawable.addFrame(getResources().getDrawable(R.drawable.ic_action_anchor), 500);
animationDrawable.addFrame(getResources().getDrawable(R.drawable.ic_action_alarm), 500);
animationDrawable.addFrame(getResources().getDrawable(R.drawable.ic_action_amazon), 500);
animationDrawable.addFrame(getResources().getDrawable(R.drawable.ic_action_ac), 500);
animationDrawable.setOneShot(false);
animationDrawable.setVisible(true,true);
return animationDrawable;
}