js實現拾色器外掛（ColorPicker）
阿新 • • 發佈：2020-05-22
對一個前端來說，顏色選擇的外掛肯定不陌生，許多小夥伴對這類外掛的實現可能會比較好奇。這裡奉上原生js版本的拾色器，由於是本人純手工擼出來的，所以轉載還請標明來源。
效果圖：
講下實現方式：
1.顏色除了RGB跟十六進位制的表現外，還有一個HSV的表現形式。H（hue）是色相，值域是0度到360度，這個值控制的是你看到的是什麼顏色，通俗點講就是紅橙黃綠...；S（saturation）是飽和度，值域是0到1，這個值控制顏色的鮮豔程度，可以理解為大紅跟淡紅的差別；V（value）可以理解為亮度，值域也是0到1。
2.rgb顏色跟hsv顏色的相互轉化有專門的公式，可自行去百度瞭解下
3.面向物件的程式設計方式公認為易擴充套件，高複用。
整個目錄結構如下：
COLORPICKER
--css
--common.css（樣式）
--js
--colorPicker.js（外掛主體）
--event.js（簡易的釋出者-訂閱者實現）
--inherite.js（繼承手段，寄生組合式）
ColorPicker.html
使用說明：
外掛目前只支援傳入h、s、v值來初始化顏色，若什麼都不傳，預設h、s、v都為0，例項化ColorPicker建構函式後，通過select方法初始化；目前只暴露了兩個回撥介面onHChange（色相改變觸發）、onSVChange（飽和度或亮度改變觸發）：
var aa = new ColorPicker();
aa.select(
// {
// h: 120,// s: 1,// b: 1
// }
);
aa.onHChange = function(e) {};
aa.onSVChange = function(e) {};程式碼如下：
ColorPicker.html：
<!DOCTYPE html>
<!--[if lt IE 7]> <html class="no-js lt-ie9 lt-ie8 lt-ie7"> <![endif]-->
<!--[if IE 7]> <html class="no-js lt-ie9 lt-ie8"> <![endif]-->
<!--[if IE 8]> <html class="no-js lt-ie9"> <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js"> <!--<![endif]-->
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<title>Color Picker</title>
<meta name="description" content="">
<meta name="viewport" content="width=device-width,initial-scale=1">
<link rel="stylesheet" href="./css/common.css" rel="external nofollow" >
</head>
<body>
</body>
<script type="text/javascript" src="js/event.js"></script>
<script type="text/javascript" src="js/inherite.js"></script>
<script type="text/javascript" src="js/colorPicker.js"></script>
</html>common.css：
body {
height: calc(100vh);
overflow: hidden;
background: gray;
}
.color-picker-container {
border: 0;
width: 300px;
margin: 0 auto;
}
.color-picker-container .val-container {
border: 1px solid silver;
text-align: center;
line-height: 30px;
font-weight: bold;
}
.color-picker-container .val-container .val {
width: 100%;
border: 0;
line-height: 32px;
text-align: center;
font-weight: bold;
}
.color-picker-container .picker-container {
position: relative;
width: 100%;
margin-top: 15px;
}
.color-picker-container .picker-container .pointer {
position: absolute;
width: 14px;
height: 14px;
border-radius: 50%;
border: 3px solid #FFFFFF;
margin-left: -9px;
margin-top: -9px;
top: 255px;
left: 0;
cursor: pointer;
}
.color-picker-container .picker-container .saturation-range {
float: left;
width: 255px;
height: 255px;
/* background-color: rgba(0,.2); */
box-shadow: 1px 1px 5px rgba(0,.6);
}
.color-picker-container .picker-container .saturation-range .cover {
width: 100%;
height: 100%;
background: -webkit-linear-gradient(top,rgb(0,0) 0%,0) 100%);
background: linear-gradient(top,0) 100%);
}
.color-picker-container .picker-container .hue-range {
float: right;
width: 30px;
height: 255px;
box-shadow: 1px 1px 5px rgba(0,.6);
background: -webkit-linear-gradient(top,rgb(255,255) 17%,255) 34%,255,255) 50%,0) 67%,0) 84%,0) 100%);
}
.color-picker-container .picker-container .hue-range .cursor {
position: relative;
width: 44px;
margin-top: -11px;
top: 255px;
cursor: n-resize;
}
.color-picker-container .picker-container .hue-range .cursor::before {
content: '';
display: inline-block;
width: 0;
height: 0;
border-style: solid;
border-top-width: 5px;
border-right-width: 0;
border-bottom-width: 5px;
border-left-width: 7px;
border-top-color: transparent;
border-bottom-color: transparent;
border-left-color: rgba(0,.5);
margin-left: -8px;
}
.color-picker-container .picker-container .hue-range .cursor::after {
content: '';
display: inline-block;
width: 0;
height: 0;
border-style: solid;
border-top-width: 5px;
border-right-width: 7px;
border-bottom-width: 5px;
border-left-width: 0;
border-top-color: transparent;
border-bottom-color: transparent;
border-right-color: rgba(0,.5);
margin-left: 33px;
}
.color-picker-container .picker-container::after {
content: '';
display: block;
clear: both;
line-height: 0;
visibility: hidden;
}
event.js：
function Event() {
this.bindEvent = [];
}
Event.prototype.addEvent = function(name,callback) {
if(typeof callback !== 'function') return;
var bExistEvent = false;
var untieEvent = function() {
if(window.removeEventListener) {
this.element.removeEventListener(name,callback);
} else if(window.detachEvent) {
this.element.detachEvent('on' + name,callback);
} else {
this.element['on' + name] = null;
}
};
for(var i = 0,len = this.bindEvent.length; i < len; i++) {
if(this.bindEvent[i].name == name) {
this.removeEvent(name);
this.bindEvent[i].untie = untieEvent;
this.bindEvent[i].event = callback;
bExistEvent = true;
break;
}
}
if(window.addEventListener) {
this.element.addEventListener(name,callback);
} else if(window.attachEvent) {
this.element.attachEvent('on' + name,callback);
} else {
this.element['on' + name] = callback;
}
if(!bExistEvent) {
this.bindEvent.push({
name: name,event: callback,untie: function() {
if(window.removeEventListener) {
this.element.removeEventListener(name,callback);
} else if(window.detachEvent) {
this.element.detachEvent('on' + name,callback);
} else {
this.element['on' + name] = null;
}
}
});
}
}
Event.prototype.removeEvent = function(name) {
if(typeof name === 'undefined' || name === '') return;
// 從已繫結事件列表中剔除
for(var i = 0,len = this.bindEvent.length; i < len; i++) {
if(this.bindEvent[i].name == name) {
this.bindEvent[i].untie.call(this); // 移除繫結事件
this.bindEvent.splice(i,1); // 從事件列表刪除
break;
}
}
}
Event.prototype.triggerEvent = function(name) {
var callback = null;
for(var i = 0,len = this.bindEvent.length; i < len; i++) {
if(this.bindEvent[i].name === name) {
callback = this.bindEvent[i].event;
}
}
if(typeof callback === 'function') {
callback.apply(this,[].slice.call(arguments).slice(1));
}
}
inherite.js：
function inheritObj(o) {
function F() {};
F.prototype = o;
return new F();
}
function inheritProto(subclass,supclass) {
subclass.prototype = inheritObj(supclass.prototype);
subclass.prototype.constructor = subclass;
}
function extend(p,o) {
for(var item in o) {
if(!p.hasOwnProperty(item)) {
p[item] = o[item];
}
}
}
function Container(className) {
this.element = null;
this.className = className || '';
this.parent = null;
this.children = [];
this.init();
}
Container.prototype.init = function() {
this.element = document.createElement(this.tagname || 'div');
this.className && (this.element.className = this.className);
}
Container.prototype.getElement = function() {
return this.element;
}
Container.prototype.add = function(item) {
item.parent = this;
this.children.push(item);
this.element.appendChild(item.getElement());
return this;
}
function Item(className,tagname) {
this.tagname = tagname || 'div';
Container.call(this,className);
delete this.children;
}
inheritProto(Item,Container);
Item.prototype.add = function() {
throw new Error('[[Type Item]] can not add any other item');
}
colorPicker.js：
(function() {
this.ColorPicker = function() {
Container.call(this);
this.hsv = [0,0];
this.rgb = [0,0];
this.svFieldHsv = [0,1,1];
this.svFieldRgb = [0,0];
}
inheritProto(ColorPicker,Container);
ColorPicker.prototype.init = function() {
this.element = document.createElement('div');
this.element.className = 'color-picker-container';
var _container = createContainer(),_self = this;
Event.call(_container);
extend(_container,Event.prototype);
createVal.call(this);
createSV.call(_container);
createH.call(_container);
_container.addEvent('sv-change',function(e) {
// 暴露出飽和度change介面
_self.onSVChange(e);
});
_container.addEvent('h-change',function(e) {
// 暴露出色相change介面
_self.onHChange(e);
});
this.add(_container);
}
ColorPicker.prototype.select = function(opt) {
if(opt && typeof opt !== 'undefined') {
this.hsv[0] = opt.h || 0;
this.hsv[1] = opt.s || 0;
this.hsv[2] = opt.b || 0;
this.svFieldHsv[0] = opt.hue || 0;
}
if(this.children[0].children[0].getElement().value !== '') {
var val = this.children[0].children[0].getElement().value,regRgb = /rgb\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)/,r = val.replace(regRgb,'$1'),g = val.replace(regRgb,'$2'),b = val.replace(regRgb,'$3');
this.hsv = rgb2hsv(r,g,b);
this.svFieldHsv[0] = this.hsv[0];
}
this.svFieldRgb = hsv2rgb(this.svFieldHsv[0],this.svFieldHsv[1],this.svFieldHsv[2]);
this.updateSVField();
this.rgb = hsv2rgb(this.hsv[0],this.hsv[1],this.hsv[2]);
this.updateSVPointer();
this.updateVal(opt);
this.children[1].children[0].getElement().style.cssText += ';left: ' + this.hsv[1] * 255 + 'px;top: ' + (255 - this.hsv[2] * 255) + 'px;';
this.children[1].children[2].children[0].getElement().style.cssText += ';top: ' + (255 - this.hsv[0]) + 'px;';
document.body.appendChild(this.element);
return this;
}
ColorPicker.prototype.updateSVField = function() {
this.children[1].children[1].getElement().style.cssText = ';background: -webkit-linear-gradient(left,255) 0%,rgb(' + ~~this.svFieldRgb[0] + ',' + ~~this.svFieldRgb[1] + ',' + ~~this.svFieldRgb[2] + ') 100%)';
}
ColorPicker.prototype.updateSVPointer = function() {
this.children[1].children[0].getElement().style.cssText += ';background-color: rgb(' + ~~this.rgb[0] + ',' + ~~this.rgb[1] + ',' + ~~this.rgb[2] + ')';
}
ColorPicker.prototype.updateVal = function() {
var _hsv_temp = [0,0];
if(this.hsv[1] < 0.5 && this.hsv[2] > 0.5) {
_hsv_temp = [this.hsv[0],0];
} else {
_hsv_temp = [this.hsv[0],1];
}
var _rgb_temp = hsv2rgb(_hsv_temp[0],_hsv_temp[1],_hsv_temp[2]);
this.children[0].children[0].getElement().style.cssText += ';text-shadow: 0 0 5px;color: rgb(' + ~~_rgb_temp[0] + ',' + ~~_rgb_temp[1] + ',' + ~~_rgb_temp[2] + ');background-color: rgb(' + ~~this.rgb[0] + ',' + ~~this.rgb[2] + ')';
this.children[1].children[0].getElement().style.cssText += ';border-color: rgb(' + ~~_rgb_temp[0] + ',' + ~~_rgb_temp[2] + ')';
this.children[0].children[0].getElement().value = 'rgb(' + ~~this.rgb[0] + ',' + ~~this.rgb[2] + ')';
}
ColorPicker.prototype.onSVChange = function(callVal) {
arguments.callee.call(this,callVal);
return this;
}
ColorPicker.prototype.onHChange = function(callVal) {
arguments.callee.call(this,callVal);
return this;
}
function createVal() {
var _container = new Container('val-container'),_input = new Item('val','input');
Event.call(_input);
extend(_input,Event.prototype);
_input.addEvent('blur',this.select.bind(this));
_container.add(_input);
this.add(_container);
}
function createContainer() {
var _container = new Container('picker-container');
return _container;
}
function createSV() {
var _pointer = new Item('pointer'),_saturationRange = new Container('saturation-range'),_cover = new Item('cover'),_self = this;
Event.call(_pointer);
extend(_pointer,Event.prototype);
_saturationRange.add(_cover);
function cursorDown(e) {
var _top = typeof e.target.style.top === 'undefined' ? 255 : parseFloat(e.target.style.top),_left = typeof e.target.style.left === 'undefined' ? 0 : parseFloat(e.target.style.left),_distanceY,_distanceX,realTop,realLeft;
function move(e2) {
_distanceY = e2.clientY - e.clientY;
_distanceX = e2.clientX - e.clientX;
realTop = _top + _distanceY;
realLeft = _left + _distanceX;
realTop < 0 && (realTop = 0);
realTop > 255 && (realTop = 255);
realLeft < 0 && (realLeft = 0);
realLeft > 255 && (realLeft = 255);
e.target.style.top = realTop + 'px';
e.target.style.left = realLeft + 'px';
_self.parent.hsv[1] = realLeft / 255;
_self.parent.hsv[2] = (255 - realTop) / 255;
_self.parent.rgb = hsv2rgb(_self.parent.hsv[0],_self.parent.hsv[1],_self.parent.hsv[2]);
_self.parent.updateSVPointer();
_self.parent.updateVal();
}
function up() {
document.removeEventListener('mousemove',move);
document.removeEventListener('mouseup',up);
_self.triggerEvent('sv-change',[realLeft / 255,(255 - realTop) / 255]);
}
document.addEventListener('mousemove',move);
document.addEventListener('mouseup',up);
}
_pointer.addEvent('mousedown',cursorDown);
this.add(_pointer)
.add(_saturationRange);
}
function createH() {
var _hueRange = new Container('hue-range'),_cursor = new Item('cursor'),_self = this;
Event.call(_cursor);
extend(_cursor,Event.prototype);
function cursorDown(e) {
var _top = typeof e.target.style.top === 'undefined' ? 255 : parseFloat(e.target.style.top),_distance,realTop;
function move(e2) {
_distance = e2.clientY - e.clientY;
realTop = _top + _distance;
realTop < 0 && (realTop = 0);
realTop > 255 && (realTop = 255);
e.target.style.top = realTop + 'px';
_self.parent.svFieldHsv[0] = 255 - realTop;
_self.parent.svFieldRgb = hsv2rgb(_self.parent.svFieldHsv[0],_self.parent.svFieldHsv[1],_self.parent.svFieldHsv[2]);
_self.parent.updateSVField();
_self.parent.hsv[0] = 255 - realTop;
_self.parent.rgb = hsv2rgb(_self.parent.hsv[0],up);
_self.triggerEvent('h-change',255 - realTop);
}
document.addEventListener('mousemove',up);
}
_cursor.addEvent('mousedown',cursorDown);
_hueRange.add(_cursor);
this.add(_hueRange);
}
function hsv2rgb(h,s,v) {
h = h / 255 * 360;
var hi = Math.floor(h / 60) % 6,f = h / 60 - Math.floor(h / 60),p = v * (1 - s),q = v * (1 - f * s),t = v * (1 - (1 - f) * s),c = [
[v,t,p],[q,v,[p,t],q,v],[t,p,[v,q]
][hi];
return [c[0] * 255,c[1] * 255,c[2] * 255];
}
function rgb2hsv(r,b) {
var max = Math.max(r,b),min = Math.min(r,h,d = max - min;
if (max == min) {
h = 0;
} else if (max == r) {
h = 60 * ((g - b) / d);
} else if (max == g) {
h = 60 * ((b - r) / d) + 120;
} else {
h = 60 * ((r - g) / d) + 240;
}
s = max == 0 ? 0 : (1 - min / max);
v = max;
if(h < 0) {
h += 360;
}
return [h * 255 / 360,v / 255];
}
})()
var aa = new ColorPicker();
aa.select(
// {
// h: 120,// b: 1
// }
);
aa.onHChange = function(e) {};
aa.onSVChange = function(e) {};
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支援我們。