element/packages/carousel/src/item.vue

110 lines
2.9 KiB
Vue

<template>
<div
v-show="ready"
class="el-carousel__item"
:class="{
'is-active': active,
'el-carousel__item--card': $parent.type === 'card',
'is-in-stage': inStage,
'is-hover': hover
}"
@click="handleItemClick"
:style="{
msTransform: `translateX(${ translate }px) scale(${ scale })`,
webkitTransform: `translateX(${ translate }px) scale(${ scale })`,
transform: `translateX(${ translate }px) scale(${ scale })`
}">
<div
v-if="$parent.type === 'card'"
v-show="!active"
class="el-carousel__mask">
</div>
<slot></slot>
</div>
</template>
<script>
const CARD_SCALE = 0.83;
export default {
name: 'ElCarouselItem',
props: {
name: String,
label: {
type: [String, Number],
default: ''
}
},
data() {
return {
hover: false,
translate: 0,
scale: 1,
active: false,
ready: false,
inStage: false
};
},
methods: {
processIndex(index, activeIndex, length) {
if (activeIndex === 0 && index === length - 1) {
return -1;
} else if (activeIndex === length - 1 && index === 0) {
return length;
} else if (index < activeIndex - 1 && activeIndex - index >= length / 2) {
return length + 1;
} else if (index > activeIndex + 1 && index - activeIndex >= length / 2) {
return -2;
}
return index;
},
calculateTranslate(index, activeIndex, parentWidth) {
if (this.inStage) {
return parentWidth * ((2 - CARD_SCALE) * (index - activeIndex) + 1) / 4;
} else if (index < activeIndex) {
return -(1 + CARD_SCALE) * parentWidth / 4;
} else {
return (3 + CARD_SCALE) * parentWidth / 4;
}
},
translateItem(index, activeIndex) {
const parentWidth = this.$parent.$el.offsetWidth;
const length = this.$parent.items.length;
if (index !== activeIndex && length > 2) {
index = this.processIndex(index, activeIndex, length);
}
if (this.$parent.type === 'card') {
this.inStage = Math.round(Math.abs(index - activeIndex)) <= 1;
this.active = index === activeIndex;
this.translate = this.calculateTranslate(index, activeIndex, parentWidth);
this.scale = this.active ? 1 : CARD_SCALE;
} else {
this.active = index === activeIndex;
this.translate = parentWidth * (index - activeIndex);
}
this.ready = true;
},
handleItemClick() {
const parent = this.$parent;
if (parent && parent.type === 'card') {
const index = parent.items.indexOf(this);
parent.setActiveItem(index);
}
}
},
created() {
this.$parent && this.$parent.updateItems();
},
destroyed() {
this.$parent && this.$parent.updateItems();
}
};
</script>