现象描述：
stack组件下使用两个image组件堆叠，一个image组件通过动画样式设置透明度从1-0，隐藏起来，另一张显示出来，从而来实现图片切换，前一张图片会概率性的闪现然后消失。
问题代码如下：
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<template>??<div?class="page-wrapper">????<input?type="button"?class="button"?onclick="onCallAnimationClick"?value="Animation?动画"?/>????<stack?style="width:400px;height:400px">????<image?class="img"?id="img1"?src="{{imgUrl}}"?oncomplete="imgcomplete"></image>?????<image?class="img"?id="img2"?if="{{ximg}}"?src="{{preUrl}}"?oncomplete="imgcomplete2"?style="{{‘opacity:‘?+?preop?+?‘;‘}}"></image>????</stack>??</div></template>??<script>export?default?{??data:?{?????imgsrc:?["https://ss1.bdstatic.com/70cFuXSh_Q1YnxGkpoWK1HF6hhy/it/u=1603365312,3218205429&fm=26&gp=0.jpg",????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fimg.aiimg.com%2Fuploads%2Fuserup%2F0909%2F2Z64022L38.jpg&refer=http%3A%2F%2Fimg.aiimg.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=879ac47e0bd97e413b5462946d9ae4ed",????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fpic3.16pic.com%2F00%2F01%2F11%2F16pic_111395_b.jpg&refer=http%3A%2F%2Fpic3.16pic.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=70c702a55248113dafa6e243dc253625",????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fa2.att.hudong.com%2F27%2F81%2F01200000194677136358818023076.jpg&refer=http%3A%2F%2Fa2.att.hudong.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=11199190c6ac8e3371f16d7568d40daa",?????"https://ss1.bdstatic.com/70cFuXSh_Q1YnxGkpoWK1HF6hhy/it/u=1089874897,1268118658&fm=26&gp=0.jpg",?????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fa3.att.hudong.com%2F92%2F04%2F01000000000000119090475560392.jpg&refer=http%3A%2F%2Fa3.att.hudong.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=3b33c5b006bcba88a24d03cfbca1ad20",?????"https://ss0.baidu.com/7Po3dSag_xI4khGko9WTAnF6hhy/zhidao/pic/item/9c16fdfaaf51f3de9ba8ee1194eef01f3a2979a8.jpg",?????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fa1.att.hudong.com%2F62%2F02%2F01300542526392139955025309984.jpg&refer=http%3A%2F%2Fa1.att.hudong.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=6500d50b1680d27bb60fe044e90ce41b",???????????????????],????imgUrl:‘‘,????preUrl:‘‘,????ximg:true,????preop:0,????i:0??},??onInit:?function?()?{??????this.imgUrl?=?this.imgsrc[0]??},??onCallAnimationClick()?{?????if(this.i?>?6){?????this.i?=?0?;?????this.imgUrl?=?this.imgsrc[this.i]???}else{????????this.i++???this.imgUrl?=?this.imgsrc[this.i]???}?????console.log(‘imgcomplete=‘,this.i)???},???imgcomplete(){????console.log(‘imgcomplete?1‘)??????this.preop?=?1??????var?options?=?{????????duration:?500,????????easing:?‘linear‘,????????delay:?0,????????fill:?‘forwards‘,????????iterations:?1??????}????????var?frames?=?[{????????opacity:?1??????},??????{????????opacity:?0??????}];??????var?animation?=?this.$element(‘img2‘).animate(frames,?options);??????animation.play();???????var?self?=?this??????animation.onfinish?=?function?()?{????????console.log("imgcomplete?animation??onfinish");????????self.ximg?=?false????????self.preop?=?0????????setTimeout(()?=>?{??????????self.ximg?=?true??????????self.preUrl?=?self.$element("img1").attr.src????????},?30);????????}????},??imgcomplete2()?{??????console.log(‘imgcomplete?2‘)??????setTimeout(()?=>?{????????this.preop?=?1??????},?50);????},}</script>??<style>.page-wrapper?{??flex-direction:?column;??justify-content:?center;??align-items:?center;}.img{??width:100%;??height:100%;}.button?{??color:?#20a0ff;??background-color:?#ffffff;??padding:?10px?20px;??border:?1px?solid?#20a0ff;??border-radius:?40px;}</style> |
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上述代码用两个image组件实现了图片切换时淡入淡出的动画效果，主要是通过透明度实现的。第二个image的css中设置了透明度，但是imgcomplete()方法中又对该image组件做了透明度动画，透明度值从1到0，同时代码中又将css中绑定的透明度变量preop设置为1。
当动画方法完成时间先于css，就会出现这个情况。
template中第二个image组件的style="{{‘opacity:‘ + preop + ‘;‘}}"去掉，改为通过动画样式来调用，从0-1变化。
修改代码如下：
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<template>??<div?class="page-wrapper">????<input?type="button"?class="button"?onclick="onCallAnimationClick"?value="Animation?动画"?/>????<stack?style="width:400px;height:400px">????<image?class="img"?id="img1"?src="{{imgUrl}}"?oncomplete="imgcomplete"></image>?????<image?class="img"?id="img2"?if="{{ximg}}"?src="{{preUrl}}"?oncomplete="imgcomplete2"?></image>????</stack>??</div></template>??<script>export?default?{??data:?{????imgsrc:?["https://ss1.bdstatic.com/70cFuXSh_Q1YnxGkpoWK1HF6hhy/it/u=1603365312,3218205429&fm=26&gp=0.jpg",????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fimg.aiimg.com%2Fuploads%2Fuserup%2F0909%2F2Z64022L38.jpg&refer=http%3A%2F%2Fimg.aiimg.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=879ac47e0bd97e413b5462946d9ae4ed",????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fpic3.16pic.com%2F00%2F01%2F11%2F16pic_111395_b.jpg&refer=http%3A%2F%2Fpic3.16pic.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=70c702a55248113dafa6e243dc253625",????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fa2.att.hudong.com%2F27%2F81%2F01200000194677136358818023076.jpg&refer=http%3A%2F%2Fa2.att.hudong.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=11199190c6ac8e3371f16d7568d40daa",?????"https://ss1.bdstatic.com/70cFuXSh_Q1YnxGkpoWK1HF6hhy/it/u=1089874897,1268118658&fm=26&gp=0.jpg",?????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fa3.att.hudong.com%2F92%2F04%2F01000000000000119090475560392.jpg&refer=http%3A%2F%2Fa3.att.hudong.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=3b33c5b006bcba88a24d03cfbca1ad20",?????"https://ss0.baidu.com/7Po3dSag_xI4khGko9WTAnF6hhy/zhidao/pic/item/9c16fdfaaf51f3de9ba8ee1194eef01f3a2979a8.jpg",?????"https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fa1.att.hudong.com%2F62%2F02%2F01300542526392139955025309984.jpg&refer=http%3A%2F%2Fa1.att.hudong.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=jpeg?sec=1611368024&t=6500d50b1680d27bb60fe044e90ce41b",???????????????????],????imgUrl:‘‘,????preUrl:‘‘,????ximg:true,????preop:0,????i:0??},??onInit:?function?()?{??????this.imgUrl?=?this.imgsrc[0]??},??????...?????//省略??imgcomplete2()?{??????console.log(‘imgcomplete?2‘)??????var?options?=?{????????duration:?10,????????easing:?‘linear‘,????????delay:?0,????????fill:?‘forwards‘,????????iterations:?1??????}??????var?frames?=?[{????????opacity:?0??????},??????{????????opacity:?1??????}];??????var?animation?=?this.$element(‘img2‘).animate(frames,?options);??????animation.play();????},}</script> |
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欲了解更多详情，请参见：
快应用动画：
https://developer.huawei.com/consumer/cn/doc/development/quickApp-References/quickapp-api-animate
快应用通用样式：
https://developer.huawei.com/consumer/cn/doc/development/quickApp-References/quickapp-common-settings#h1-1575449213432
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原文链接：https://developer.huawei.com/...
原作者：Mayism
原文：https://blog.51cto.com/u_14772288/3254909