notification.js

var notificationCenter = {

    notificationCenter:{},

    // 向通知中心注册一个监听者。
    // name: 监听的通知名称
    // observer: 监听者
    // action: 监听者收通知时调用的方法名，
    // func: 监听者收到通知时调用的函数，
    // action func 2选1
    register:function(name,observer,action,func){
        if (!name || !observer) return;
        if (!action && !func) return;

        console.log("注册通知：",name,observer);

        var center = this.notificationCenter;
        var objects = center[name];
        if (!objects){
            objects = [];
        }
        this.remove(name,observer);
        objects.push({
            observer:observer,
            action:action,
            func:func
        });
        center[name] = objects;
    },
    // 从通知中心移除一个监听者
    remove:function(name,observer){
        if (!name || !observer) return;

        var center = this.notificationCenter;
        var objects = center[name];
        if (!objects){
            return;
        }

        var idx;
        var object;
        for(idx = 0;idx<objects.length;idx++){
            var obj = objects[idx];
            if (obj.observer == observer){
            object = obj;
            break;
            }
        }
        if (object){
            objects.splice(idx,1);
        }
        center[name] = objects;
    },
    // 通过通知中心发出通知
    // name: 通知名称
    // notification: 通知内容
    post:function(name,notification){
        if (!name) return;

        console.log("准备发出通知：",name);

        var objects = this.notificationCenter[name];
        if (!objects || objects.length == 0){
            return;
        }
        if(!notification){
            notification = {};
        }
        notification.name = name;
        objects.forEach(function(object){
            if (object.observer){
                var func;
                if (object.action){
                    func = object.observer[object.action];
                }
                if (!func){
                    func = object.func;
                }
                if (func){
                    notification._this = object.observer;
                    func(notification);
                }
            }
        });
        console.log("完成向 ",objects.length," 个监听者发出通知：",name);
    }
}

function center(){
    return notificationCenter;
}

module.exports.center = center;