题解 | #选择组件#

function CheckGroup(renderTo, options, isMultiple) {
var that = this;
that.renderTo = renderTo;
that.options = options;
that.isMultiple = !!isMultiple;
that.initHtml();
that.initEvent();
}
CheckGroup.prototype.initHtml = fInitHtml;
CheckGroup.prototype.initEvent = fInitEvent;
CheckGroup.prototype.toggleEl = fToggleEl;
CheckGroup.prototype.isSelected = fIsSelected;
CheckGroup.prototype.val = fVal;

function fInitHtml() {
var that = this;
// 请补全代码，拼接html字符串
var sHtml = `<div class="checkgroup{item.value}" class="item">${item.text}`
return sHtml
})
that.renderTo.innerHTML = sHtml+"";
// 请补全代码，获取checkgroup的dom元素引用
that.el = document.querySelector('.checkgroup');
}

function fInitEvent() {
var that = this;
that.el && that.el.addEventListener('click', function (event) {
var item = event.target;
item.classList.contains('item') && that.toggleEl(item);
});
}

function fToggleEl(item) {
// 根据当前是单选还是多选，以及当前元素是否选中，高亮/取消���亮指定的选项dom元素
var that = this;
if (that.isSelected(item)) {
// 请补全代码
item.classList.remove('selected')
} else if (that.isMultiple) {
// 请补全代码
item.classList.add('selected')
} else {
// 请补全代码
[...that.el.children].map(i => i.classList.remove('selected'))
item.classList.add('selected')
}
that.val();
}

function fIsSelected(item) {
// 请补全代码，判断item是否选中
return item.classList.contains("selected");
}

function fVal(values) {
var that = this;
if (arguments.length === 0) {
// 请补全代码，获取高亮的选项元素
var items = document.getElementsByClassName("selected");
// 请补全代码，获取高亮的选项元素的data-val
var result = [];
for(let i = 0; i<items.length; i++){
let item = items[i];
result.push(item.getAttribute('data-val'));
}
return result;
}
!that.isMultiple && values.length > 1 && (values.length = 1);
// 请补全代码，获取所有的选项元素
var items = document.getElementsByClassName("item");
// 请补全代码，在指定元素上加上高亮的class
for(let i = 0; i<items.length; i++){
let item = items[i];
if (values.includes(item.getAttribute('data-val'))) {
item.classList.add("selected")
} else {
item.className = 'item';
}
}
}