clay-core/src/event.js

Provide a more friendly web-side drawing interface!

_clay_prototype.bind = function (eventType, callback) {

    var flag;
    if (window.attachEvent)
        for (flag = 0; flag < this.length; flag++)
            // 后绑定的先执行
            this[flag].attachEvent("on" + eventType, callback);
    else
        for (flag = 0; flag < this.length; flag++)
            // 捕获
            this[flag].addEventListener(eventType, callback, false);
    return this;

};

_clay_prototype.trigger = function (eventType) {
    var flag, event;

    //创建event的对象实例。
    if (document.createEventObject) {
        // IE浏览器支持fireEvent方法
        event = document.createEventObject();
        for (flag = 0; flag < this.length; flag++) {
            this[flag].fireEvent('on' + eventType, event);
        }
    }

    // 其他标准浏览器使用dispatchEvent方法
    else {
        event = document.createEvent('HTMLEvents');
        // 3个参数：事件类型，是否冒泡，是否阻止浏览器的默认行为
        event.initEvent(eventType, true, false);
        for (flag = 0; flag < this.length; flag++) {
            this[flag].dispatchEvent(event);
        }
    }

    return this;
};

/*
 ************************************
 * 事件相关计算方法
 */

//  获取鼠标相对特定元素左上角位置
_clay_prototype.position = function (event) {

    var bounding = this[0].getBoundingClientRect();

    return {
        "x": event.clientX - bounding.left,
        "y": event.clientY - bounding.top
    };

};