Recently delving into the world of Vue, I've been grappling with how to display a nested list visually.
In this list, each item should feature a triple-state checkbox system: When a child item is checked, the parent item's checkbox should become 'indeterminate'. If all child-checkboxes are checked, then the parent checkbox should also become checked. Additionally, if a parent item checkbox is checked, all child item checkboxes (even those nested deeper) should be selected as well.
Although I have a partially functional solution (have a look at this pen or the code snippet provided below), the checkbox logic still needs fine-tuning. In this demonstration, checked boxes are represented in green, indeterminate ones in orange, and unchecked ones in red.
I've hit a roadblock in resolving this issue. Can anyone offer some guidance on how to achieve this functionality in Vue?
'use strict';
Vue.component("book-chapter", Vue.extend({
name: "book-chapter",
props: ["data", "current-depth"],
data: function() {
return {
checked: this.data.checked,
indeterminate: this.data.indeterminate || false
};
},
methods: {
isChecked: function() {
return this.checked && !this.indeterminate;
},
isIndeterminate: function(){
return this.indeterminate;
},
toggleCheckbox: function(eventData) {
if (this.currentDepth > 0){
if (!this.data.children) {
this.checked != this.children
} else {
this.indeterminate = !this.indeterminate;
}
}
if (eventData) {
// fired by nested chapter
this.$emit('checked', eventData);
} else {
// fired by top level chapter
this.checked = !this.checked;
this.$emit('checked', {
data: this.data
});
}
},
isRootObject: function() {
return this.currentDepth === 0;
},
isChild: function() {
return this.currentDepth === 2;
},
isGrandChild: function() {
return this.currentDepth > 2;
}
},
template: `
<div class='book__chapters'>
<div
class='book__chapter'
v-bind:class="{ 'book__chapter--sub': isChild(), 'book__chapter--subsub': isGrandChild() }"
v-show='!isRootObject()'>
<div class='book__chapter__color'></div>
<div
class='book__chapter__content'
v-bind:class="{ 'book__chapter__content--sub': isChild(), 'book__chapter__content--subsub': isGrandChild() }">
<div class='book__chapter__title'>
<span class='book__chapter__title__text'>{{data.title}}</span>
</div>
<div class='book__chapter__checkbox triple-checkbox'>
<div class='indeterminatecheckbox'>
<div
class='icon'
@click.stop="toggleCheckbox()"
v-bind:class="{'icon--checkbox-checked': isChecked(), 'icon--checkbox-unchecked': !isChecked(), 'icon--checkbox-indeterminate': isIndeterminate()}">
</div>
</div>
</div>
</div>
</div>
<book-chapter
ref='chapter'
:current-depth='currentDepth + 1'
v-for='child in data.children'
:key='child.id'
@checked='toggleCheckbox(arguments[0])'
:data='child'>
</book-chapter>
</div>
`
}));
Vue.component("book", Vue.extend({
name: "book",
props: ["data"],
template: `
<div class='book'>
<book-chapter
:data='this.data'
:currentDepth='0'>
</book-chapter>
</div>
`
}));
var parent = new Vue({
el: "#container",
data: function() {
return {
book: {}
};
},
mounted: function() {
this.book = {
"title": "Book",
"children": [{
"title": "1 First title",
"children": [{
"title": "1.1 Subtitle"
}, {
"title": "1.2 Subtitle"
}]
}, {
"title": "2 Second title",
"children": [{
"title": "2.1 Subtitle",
"children": [{
"title": "2.1.1 Sub-Sub title"
}, {
"title": "2.1.2 Another sub-sub title"
}]
}]
}]
}
}
});