使用animateTo循环播放动画时刷新状态变量无法刷新UI

问题现象
在使用animateTo方法实现循环动画的过程中，如果希望在每次动画播放时通过更新状态变量来刷新UI，可能会遇到UI无法动态响应更新的问题。例如，即使在事件中配置状态变量changeNum每次播放增加1，并设置动画循环播放3次，实际的UI显示仅更新一次，而onFinish的回调中changeNum仅记录1。

@Entry
@Component
struct AnimateToExample {
@State widthSize: number = 250;
@State heightSize: number = 100;
uiContext: UIContext | undefined = undefined;
@State changeNum: number = 0;
aboutToAppear() {
this.uiContext = this.getUIContext();
if (!this.uiContext) {
console.warn('no uiContext');
return;
}
}
playLrc() {
this.uiContext?.animateTo({
duration: 2000,
curve: Curve.EaseOut,
iterations: 3,
playMode: PlayMode.Normal,
onFinish: () => {
console.info('play end');
}
}, () => {
this.widthSize = 300;
this.heightSize = 60;
this.changeNum++;
});
}
build() {
Column() {
Button(this.changeNum.toString())
.width(this.widthSize)
.height(this.heightSize)
.margin(30)
.onClick(() => {
this.playLrc();
});
}.width('100%').margin({ top: 5 });
}
}
问题效果预览：

点击放大

背景知识
animateTo：提供animateTo接口来指定由于闭包代码导致的状态变化插入过渡动效。
关键帧动画 (keyframeAnimateTo)：在UIContext中提供keyframeAnimateTo接口来指定若干个关键帧状态，实现分段的动画。
解决方案
显示动画的参数iterations表示动画的执行次数，并不代表闭包函数里面的逻辑执行次数，所以问题代码中iterations:3并不会使得修改宽高动画执行3次，需要使用关键帧动画。
使用关键帧动画，可以分段执行动画逻辑。在动画结束后在onFinish回调中递归执行动画，从而实现预期效果。
@Entry
@Component
struct AnimateToExample {
@State widthSize: number = 250;
@State heightSize: number = 100;
uiContext: UIContext | undefined = undefined;
@State changeNum: number = 0;

aboutToAppear() {
this.uiContext = this.getUIContext();
};

playLrc() {
// 使用关键帧动画
this.uiContext?.keyframeAnimateTo({
iterations: 1,
onFinish: () => {
if (this.changeNum % 3 !== 0) {
this.playLrc();
}
}
}, [
{
// 第一段关键帧动画
duration: 800,
event: () => {
this.widthSize = 300;
this.heightSize = 60;
this.changeNum++;
}
},
// 第二段关键帧动画
{
duration: 500,
event: () => {
this.widthSize = 250;
this.heightSize = 100;
}
}
]);
}

build() {
Column() {
Button(this.changeNum.toString())
.width(this.widthSize)
.height(this.heightSize)
.margin(30)
.onClick(() => {
this.playLrc();
});
}.width('100%').margin({ top: 5 });
}
}
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