2

我正在编写一个 jQuery 插件,我需要通过我的插件方法调用来保留对象。所以我尝试.data()按照这里的建议使用:http: //docs.jquery.com/Plugins/Authoring

但我无法检索我存储的对象,这里是我的代码:

(function($) {
    var methods = {
        init : function(options) {
            return this.each(function() {
                var $this = $(this);
                var geocoder = new google.maps.Geocoder();
                var settings = {
                    'geocodeSearch': {address: 'France'}
                };

                // Merge default settings with user ones
                if (options) {
                    $.extend(settings, options);
                }

                function drawMap(geocodeResult) {
                    var mapSettings = {
                        center: geocodeResult[0].geometry.location,
                        mapTypeControl: true,
                        mapTypeId: google.maps.MapTypeId.SATELLITE,
                        overviewMapControl: false,
                        panControl: true,
                        scaleControl: true,
                        streetViewControl: false,
                        zoom: 6,
                        zoomControl: true,
                        zoomControlOptions: { style: google.maps.ZoomControlStyle.SMALL }
                    };

                    var element = document.getElementById($this.attr("id"));
                    var map = new google.maps.Map(element, mapSettings);
                    var cluster = new MarkerClusterer(map);

                    cluster.setGridSize(100);

                    $this.data('eventsmap', {
                        cluster: cluster,
                        map: map
                    });
                }

                    geocoder.geocode(settings.geocodeSearch, drawMap);
            });
        },
        restrictZoom : function(minimalZoom, maximalZoom) {
            return this.each(function() {
                var $this = $(this);
                console.log($this.data());
                console.log($this.data('eventsmap'));

                //google.maps.event.addListener(map, 'zoom_changed', function() {
                //  if (map.getZoom() > maximalZoom) {
                //      map.setZoom(maximalZoom);
                //  }
                //  if (map.getZoom() < minimalZoom) {
                //      map.setZoom(minimalZoom);
                //  }
                //});
                //cluster.setMaxZoom(maximalZoom-1);
            });
        }
    };

    $.fn.eventsMap = function(method) {
        if (methods[method]) {
            return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
        } else if (typeof method === 'object' || !method) {
            return methods.init.apply(this, arguments);
        } else {
            $.error( 'Method ' +  method + ' does not exist on jQuery.eventsMap' );
        }
    };
})(jQuery);

当我调用 restrictZoom 方法时,$this.data()(第 48 行)从 DOM 返回数据,但如果我尝试获取在 init 方法期间设置的 'eventsmap' 属性,我得到 undefined ($this.data('eventsmap ')第 49 行)。我确定它是正确的 DOM 对象,我的对象是因为我可以通过浏览器调试器看到它​​们:

铬输出

我不知道该怎么办。

编辑:html:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-us" xml:lang="en-us" > 
<head> 
<title>Map tool | Django site admin</title> 
<link rel="stylesheet" type="text/css" href="/static/admin/css/base.css" /> 

<link rel="stylesheet" type="text/css" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.11/themes/ui-darkness/jquery-ui.css" /> 

<!--[if lte IE 7]><link rel="stylesheet" type="text/css" href="/static/admin/css/ie.css" /><![endif]--> 

<script type="text/javascript">window.__admin_media_prefix__ = "/static/admin/";</script> 

<script type="text/javascript" src="https://maps.google.com/maps/api/js?sensor=false"></script> 
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js"></script> 
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.11/jquery-ui.js"></script> 
<script type="text/javascript" src="/static/earthquake/js/markerclusterer.js"></script> 
<script type="text/javascript" src="/static/earthquake/js/map.js"></script> 

<meta name="robots" content="NONE,NOARCHIVE" /> 
</head> 


<body class="eventsmap"> 

<!-- Container --> 
<div id="container"> 


    <!-- Header --> 
    <div id="header"> 
        <div id="branding"> 
        <h1 id="site-name">Events database</h1> 
        </div> 

        <div id="user-tools"> 
            Welcome,
            <strong>admin</strong>.



                    <a href="/admin/doc/">Documentation</a> /



                    <a href="/admin/password_change/"> 

                Change password</a> /


                    <a href="/admin/logout/"> 

                Log out</a> 

        </div> 


    </div> 
    <!-- END Header --> 

<div class="breadcrumbs"> 
<a href="/admin/">Home</a> &rsaquo; <a href="/admin/events">Events</a> &rsaquo; Map tool
</div> 





    <!-- Content --> 
    <div id="content" class="colM"> 



<div id="eventsmap" style="width: 100%;"></div> 
<script> 
$(document).ready(function() {
    var mapCanvas = $("#eventsmap");

    // Cleanup and prepare HTML from Django
    $("#footer").remove();
    $("html").height("100%");
    $("body").height("100%");
    $("body").css("overflow-y", "hidden");
    $("#content").css('margin', 0);
        mapCanvas.height($(document).height()-57);

    mapCanvas.eventsMap({
        geocodeSearch: {address: 'France'}
    });
    mapCanvas.eventsMap('restrictZoom', {
        minimalZoom: 2,
        maximalZoom: 9
    });
});
</script> 


        <br class="clear" /> 
    </div> 
    <!-- END Content --> 

    <div id="footer"></div> 
</div> 
<!-- END Container --> 

</body> 
</html> 
4

2 回答 2

0

总的来说,代码看起来非常好。但这里有两个想法:

  1. 您是否尝试在该数据函数中存储更简单的对象文字以确保代码以其他方式工作?您当前正在存储一个 Google Map 对象和一个 MarkerCluster。这些对象是否过于复杂而无法编码为 json 并存储在数据属性中?(不记得它们是否只是对象文字,或者它们是否还有函数和其他元素)

  2. 只是一种风格上的东西,但是有许多重用的名称使得调试代码变得更加困难。(总体而言,您的代码很棒)有两个不同的变量名为 $this (在不同的范围内它看起来像)和三个名为 eventsmap 的项目(一个 css 类、一个 js 变量和一个扩展函数)。虽然它们可能很好,但可能会让一些阅读此代码的人绊倒。

我希望这能激发一些想法!

于 2011-04-27T15:13:25.333 回答
0

我终于弄清楚了为什么它不起作用,我必须确保插件方法是同步调用的。为了实现这一点,我将我的方法包装在 jQuery .queue 函数中,如下所示:

(function($) {
var methods = {
    init : function(options) {
        return this.each(function() {
            $(this).queue(function() {
                var $this = $(this), data = $this.data('eventsmap');
                var geocoder = new google.maps.Geocoder();
                var settings = {
                    'geocodeSearch': {address: 'France'}
                };

                // Merge default settings with user ones
                if (options) {
                    $.extend(settings, options);
                }

                function drawMap(geocodeResult) {
                    var mapSettings = {
                        center: geocodeResult[0].geometry.location,
                        mapTypeControl: true,
                        mapTypeId: google.maps.MapTypeId.SATELLITE,
                        overviewMapControl: false,
                        panControl: true,
                        scaleControl: true,
                        streetViewControl: false,
                        zoom: 6,
                        zoomControl: true,
                        zoomControlOptions: { style: google.maps.ZoomControlStyle.SMALL }
                    };

                    var element = document.getElementById($this.attr("id"));
                    var map = new google.maps.Map(element, mapSettings);
                    var cluster = new MarkerClusterer(map);

                    cluster.setGridSize(100);

                    if (!data) {
                        $this.data('eventsmap', {
                            cluster: cluster,
                            map: map
                        });
                    }
                    $this.dequeue();
                }

                geocoder.geocode(settings.geocodeSearch, drawMap);
            })
        });
    },
    restrictZoom : function(args) {
        var minimalZoom = args.minimalZoom;
        var maximalZoom = args.maximalZoom;

        return this.each(function() {
            $(this).queue(function() {
                var $this = $(this), data = $this.data('eventsmap');

                google.maps.event.addListener(data.map, 'zoom_changed', function() {
                    if (data.map.getZoom() > maximalZoom) {
                        data.map.setZoom(maximalZoom);
                    }
                    if (data.map.getZoom() < minimalZoom) {
                        data.map.setZoom(minimalZoom);
                    }
                });

                data.cluster.setMaxZoom(args.maximalZoom-1);

                $(this).dequeue();
            });
        });
    }
};

$.fn.eventsMap = function(method) {
    if (methods[method]) {
        return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
    } else if (typeof method === 'object' || !method) {
        return methods.init.apply(this, arguments);
    } else {
        $.error( 'Method ' +  method + ' does not exist on jQuery.eventsMap' );
    }
};
})(jQuery);

现在它就像一个魅力,我在 init 方法设置之前调用 myObject.data('eventsmap') 顺便说一句我仍然无法解释为什么我可以在浏览器中看到该对象...... :)

于 2011-04-28T08:57:30.397 回答