Binding 带有多个键的对象的VueJs 2.x stylebind不起作用
我第一次摆弄vue,在正常工作方面遇到了麻烦。当styleObject中只有一个键/值对时,它可以工作,但当我有一个以上的键/值对时,就什么都没有了 运行Binding 带有多个键的对象的VueJs 2.x stylebind不起作用,binding,vuejs2,vue-component,Binding,Vuejs2,Vue Component,我第一次摆弄vue,在正常工作方面遇到了麻烦。当styleObject中只有一个键/值对时,它可以工作,但当我有一个以上的键/值对时,就什么都没有了 运行console.log() 我的vue代码: <script> import Vue from 'vue'; import ImageObject from './SkyCropImage.class'; export default Vue.component('sky-crop', { props: {
console.log()
我的vue代码:
<script>
import Vue from 'vue';
import ImageObject from './SkyCropImage.class';
export default Vue.component('sky-crop', {
props: {
src: String,
focalpoint: String,
mode: String,
round: String,
type: {
type: String,
default: 'img',
},
},
data() {
return {
image: new ImageObject(this.src),
srcString: '',
styleObject: { },
};
},
methods: {
anchorString(image) {
if (this.$el.firstChild.localName !== 'img') {
this.styleObject.backgroundPosition = `${image.anchor.x} ${image.anchor.y}`;
} else {
const pointX = (image.anchor.x.replace('%', '') * 1) / 100;
const pointY = (image.anchor.y.replace('%', '') * 1) / 100;
const differenceX = image.parent.width - image.calculatedInfo.width;
const differenceY = image.parent.height - image.calculatedInfo.height;
const anchorX = Math.min(0, differenceX * pointX);
const anchorY = Math.min(0, differenceY * pointY);
this.styleObject.transform = `translate(${anchorX}px, ${anchorY}px)`;
}
},
concatSrc(string) {
this.srcString = string;
if (this.type !== 'img') {
this.styleObject.backgroundImage = `url(${string})`;
}
},
},
created() {
this.image.mode = this.mode;
this.image.round = this.round;
this.image.anchor = {
x: this.focalpoint.split(',')[0],
y: this.focalpoint.split(',')[1],
};
},
mounted() {
this.image.setParentInfo(this.$el);
this.image.runCropJob();
this.anchorString(this.image);
this.concatSrc(this.image.outputUrl);
},
});
从“Vue”导入Vue;
从“./SkyCropImage.class”导入ImageObject;
导出默认Vue.component('sky-crop'{
道具:{
src:String,
焦点:字符串,
模式:字符串,
圆:弦,
类型:{
类型:字符串,
默认值:“img”,
},
},
数据(){
返回{
image:newImageObject(this.src),
srcString:“”,
样式对象:{},
};
},
方法:{
主持人串(图片){
if(this.$el.firstChild.localName!=='img'){
this.styleObject.backgroundPosition=`${image.anchor.x}${image.anchor.y}`;
}否则{
常量pointX=(image.anchor.x.replace('%,'')*1)/100;
常量pointY=(image.anchor.y.replace('%,'')*1)/100;
const differenceX=image.parent.width-image.calculatedInfo.width;
const differenceY=image.parent.height-image.calculatedInfo.height;
常数anchorX=数学最小值(0,差分x*pointX);
const anchorY=Math.min(0,差分y*pointY);
this.styleObject.transform=`translate(${anchorX}px,${anchorY}px)`;
}
},
concatSrc(字符串){
this.srcString=string;
if(this.type!==“img”){
this.styleObject.backgroundImage=`url(${string})`;
}
},
},
创建(){
this.image.mode=this.mode;
this.image.round=this.round;
this.image.anchor={
x:this.focalpoint.split(',')[0],
y:this.focalpoint.split(',')[1],
};
},
安装的(){
this.image.setParentInfo(this.el);
this.image.runCropJob();
this.anchorString(this.image);
this.concatSrc(this.image.outputUrl);
},
});
我的模板:
<div class="skyCrop-parent">
<img
class="skyCrop-element"
alt=""
v-if="type === 'img'"
v-bind:src="srcString"
v-bind:style="styleObject" />
// img result: <img alt="" src="https://source.unsplash.com/Ixp4YhCKZkI/700x394" class="skyCrop-element" style="transform: translate(-50px, 0px);">
<div
class="skyCrop-element"
v-bind:style="styleObject"
v-else>
</div>
//div result: <div class="skyCrop-element"></div>
</div>
//img结果:
//分区结果:
组件的调用方式:
<sky-crop
src="https://source.unsplash.com/Ixp4YhCKZkI/1600x900"
focalpoint="50%,50%"
mode="width"
round="175"
type="div">
</sky-crop>
<sky-crop
src="https://source.unsplash.com/Ixp4YhCKZkI/1600x900"
focalpoint="50%,50%"
mode="width"
round="175">
</sky-crop>
漏洞在于Vue处理反应性的方式 因为我尝试向
styleObject
添加键/值对,如下所示:
this.styleObject.backgroundPosition = `${image.anchor.x} ${image.anchor.y}`;
Vue无法检测到更改,因为我尝试引用的密钥没有事先声明。解决方案可以是定义所有的未来,也可以是关键,这将很好地工作。但是,使用vm.$set()
会更好,因为它可以处理密钥的创建并同时启动反应。简而言之,这一行(以及其他做同样事情的人):
变成这样:
this.$set(this.styleObject, 'background-position', `${image.anchor.x} ${image.anchor.y}`);
有关更改原因的Vue文档:
this.$set(this.styleObject, 'background-position', `${image.anchor.x} ${image.anchor.y}`);