Vue js:如何在两个组件中使用 mixin 功能?通过执行错误
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【中文标题】Vue js:如何在两个组件中使用 mixin 功能?通过执行错误【英文标题】:Vue js: How to use mixin function in two components? By execution Error 【发布时间】:2022-01-03 18:20:37 【问题描述】:我有 2 个组件:父子组件和一个 mixin。我试图在他们两个中使用一个功能。从父组件中的子组件调用 mixin 函数。这个 mixin 函数也改变了父组件的 data var,它在子组件中被 props 引用。
但是,在这行代码中:
this.modals.filter = 'block'; occurs error: TypeError: Cannot set properties of undefined (setting 'filter')
我不明白为什么,因为 modals.filter 已经在 props 中被引用了?
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Test</title>
<script src="https://cdn.jsdelivr.net/npm/vue@2.6.14"></script>
</head>
<body>
<div id="example" style="width:100%;height:100%">
<parent></parent>
</div>
</body>
<script>
var myMixin =
methods:
powerbiFilterModal: function()
this.modals.filter = 'block';
if (this.embed.channelName, this.filters.columnName, this.filters.tableName)
// Some other functions
// ...
console.log(this.embed.channelName, this.filters.columnName, this.filters.tableName);
// Hide modal
this.modals.filter = 'none';
// Clear inputs
this.embed.channelName = '';
this.filters.columnName = '';
this.filters.tableName = '';
;
Vue.component('child',
mixins: [myMixin],
template: `
<div :style=" display: filterOverlay ">
<span class="close" style="align-self: flex-end; cursor: pointer;" @click="closeModal">x</span>
<span class="label" style="align-self: center; margin-bottom: 4%">Filter Settings: </span>
<input type="text" placeholder="Define channel name" v-model.trim="channelName">
<input type="text" placeholder="Define filter name" v-model.trim="columnName">
<input type="text" placeholder="Define table to filter" v-model.trim="tableName">
<button @click="powerbiFilterModal">Subscribe & Send</button>
</div>
`,
props:
filterOverlay:
type: String,
required: false,
default: 'none'
,
channelName:
type: String,
required: false
,
columnName:
type: String,
required: false
,
tableName:
type: String,
required: false
,
methods:
closeModal: function()
this.$emit('emitEv', 'none');
);
Vue.component('parent',
mixins: [myMixin],
template: `
<div>
<button @click="powerbiFilterModal">Set Filters</button>
<child @emitEv="changeOverlay" v-bind:filter-overlay="modals.filter">Child</child>
</div>
`,
data: function()
return
modals:
filter: 'none'
,
embed:
channelName: ''
,
filters:
columnName: '',
tableName: ''
,
methods:
changeOverlay: function(value)
this.modals.filter = value;
);
new Vue(
el: "#example"
);
</script>
</html>
【问题讨论】:
子this.modals
未定义
在子组件和父组件中同时使用相同的 mixin 很奇怪,你可以从子组件发出按钮点击事件,然后在父组件调用 powerbiFilterModal
@Radeanu 你能补充一下它是如何实现的吗?我检查了发出点击,但如何通过使用此类事件触发函数?
【参考方案1】:
解释我的评论
子组件
Vue.component("child",
// mixins: [myMixin], remove mixin from child
template: `
<div>
<!-- bla bla bla -->
<button @click="$emit('fire')">Subscribe & Send</button>
</div>
...
`
);
父组件
Vue.component("parent",
mixins: [myMixin],
template: `
<div>
<button @click="powerbiFilterModal">Set Filters</button>
<!-- HERE we listen for event (fire) from child and call powerbiFilterModal method from mixin -->
<child @fire="powerbiFilterModal" @emitEv="changeOverlay" v-bind:filter-overlay="modals.filter">Child</child>
</div>
`,
data: function ()
return
modals:
filter: "none"
,
embed:
channelName: ""
,
filters:
columnName: "",
tableName: ""
;
,
methods:
changeOverlay: function (value)
this.modals.filter = value;
);
【讨论】:
【参考方案2】:powerbiFilterModal()
是引用this.modals
,如果在父组件中使用是可以的,但是子组件没有这样的数据,所以在子组件中调用mixin会报错。
【讨论】:
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