Android Realizes Transparent Animation
- 2021-12-13 09:09:07
- OfStack
In this paper, we share the specific code of Android to realize transparent animation for your reference. The specific contents are as follows
Home page has 1 Activity
public class AlphaAnimationActivity extends AppCompatActivity {
private ImageView mImageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_frame_animation);
// It's just 1 An ordinary picture
mImageView = findViewById(R.id.imageview);
... Here are several buttons Used to start animation
}
1 complement animation mode
1.1 xml Mode
Directory folder res/anim/alpha. xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<alpha
android:duration="3000"
android:fromAlpha="0.0"
android:toAlpha="1.0">
</alpha>
</set>
Then use the following in Java code:
// Interval animation mode - xml
public void start1() {
// Load animation xml
Animation lAnimation = AnimationUtils.loadAnimation(this, R.anim.alpha);
// Set and turn on animation
mImageView.startAnimation(lAnimation);
}
1.2 java code mode
// Interval animation mode - java
private void start2() {
// Create Transparent Animation
Animation lAnimation = new AlphaAnimation(0.0f, 1.0f);
// Set animation time
lAnimation.setDuration(3000);
// Set animation
mImageView.startAnimation(lAnimation);
}
2 Attribute animation mode
1.1 ValueAnimator xml Mode
Directory folder res/animator/alpha_animator. xml
<animator xmlns:android="http://schemas.android.com/apk/res/android"
android:valueFrom="0"
android:valueTo="255"
android:duration="2000"
android:valueType="intType"/>
And then in the code
// Attribute animation mode - ValueAnimator - xml
public void start3() {
// Load XML Animation
ValueAnimator animator = (ValueAnimator) AnimatorInflater.loadAnimator(this, R.animator.alpha_animator);
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
int currentValue = (int) animation.getAnimatedValue();
Log.d(" Attribute animation ", "onAnimationUpdate: " + animation.getAnimatedValue());
// Assign the changed value to the property value of the object, which will be explained in detail below
mImageView.setImageAlpha(currentValue);
// Refresh the view, that is, redraw it to achieve animation effect
mImageView.requestLayout();
}
});
// Start animation
animator.start();
}
1.2 ValueAnimator java code mode
//属性动画方式 - ValueAnimator - java
public void start4() {
// 第1步:设置动画属性的初始值 & 结束值
// ofInt()作用有两个
// 1. 创建动画实例
// 2. 将传入的多个Int参数进行平滑过渡:此处传入0和1,表示将值从0平滑过渡到 255
// 如果传入了3个Int参数 a,b,c ,则是先从a平滑过渡到b,再从b平滑过渡到 c,以此类推
ValueAnimator anim = ValueAnimator.ofInt(0, 255);
// 设置动画运行的时长
anim.setDuration(500);
// 设置动画延迟播放时间
anim.setStartDelay(500);
// 设置动画重复播放次数 = 重放次数+1
// 动画播放次数 = infinite时,动画无限重复
anim.setRepeatCount(0);
// 设置重复播放动画模式
// ValueAnimator.RESTART(默认):正序重放
// ValueAnimator.REVERSE:倒序回放
anim.setRepeatMode(ValueAnimator.RESTART);
// 第2步:将改变的值手动赋值给对象的属性值:通过动画的更新监听器
// 设置 值的更新监听器
// 即:值每次改变、变化1次,该方法就会被调用1次
anim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
int currentValue = (Integer) animation.getAnimatedValue();
// 获得改变后的值
System.out.println(currentValue);
// 输出改变后的值
// 步骤4:将改变后的值赋给对象的属性值,下面会详细说明
mImageView.setImageAlpha(currentValue);
// 步骤5:刷新视图,即重新绘制,从而实现动画效果
mImageView.requestLayout();
}
});
//第3步 启动动画
anim.start();
// 启动动画
// ValueAnimator 类是先改变值,然后 手动赋值 给对象的属性从而实现动画;是 间接 对对象属性进行操作
// ValueAnimator 类本质上是1种 改变 值 的操作机制
}
1.3 ObjectAnimator xml Mode
Directory folder animator/alpha_object_animator. xml
<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
android:propertyName="alpha"
android:valueFrom="1"
android:valueTo="0"
android:duration="2000"
android:valueType="floatType"
>
</objectAnimator>
// Attribute animation mode - ObjectAnimator - xml
public void start5() {
// Load XML Animation
Animator animator = AnimatorInflater.loadAnimator(this, R.animator.alpha_object_animator);
// Setting Animation Objects
animator.setTarget(mImageView);
// Start animation
animator.start();
Log.d(" Animation ","ObjectAnimator - xml");
}
1.4 ObjectAnimator java code mode
// Attribute animation mode - ObjectAnimator - java
public void start6() {
ObjectAnimator anim = ObjectAnimator.ofFloat(mImageView, "alpha", 1f, 0f, 1f);
// Represents the :
// Animation action object is mButton
// The attribute of the animated object is transparency alpha
// The animation effect is : Routine - Full transparency - Routine
// ofFloat() There are two functions
anim.setDuration(500);
// Set how long the animation runs
anim.setStartDelay(500);
// Set the animation delay playback time
anim.setRepeatCount(0);
// Set the number of animation repetitions = Number of replays +1
// Number of animations played = infinite Hour , Infinite repetition of animation
anim.setRepeatMode(ValueAnimator.RESTART);
// Set Repeat Animation Mode
// ValueAnimator.RESTART( Default ): Positive sequence playback
// ValueAnimator.REVERSE: Reverse playback
anim.start();
}