对于尝试学习AMD风格的Dojo时遇到的某些行为，我确实感到困惑。当我实例化模块/对象时，“ this”是指构造函数中的对象。我对内部函数进行了调用，该内部函数中的“ this”是指Window对象。因此，当我访问this.attachMapEventHandlers时，出现“对象[对象全局]没有方法'attachMapEventHandlers'”错误。我究竟做错了什么？更新：我找到了lang.hitch，这似乎表明异步本质是让我绊倒的原因，但是我对如何实现解决方案感到困惑。
我在index.html中的脚本：
require(["javascript/layout", "dijit/layout/ContentPane", "dijit/layout/BorderContainer", "dijit/layout/AccordionContainer",
"dojo/dom", "dojo/dom-attr", "dijit/Toolbar", "dijit/form/Button", "dijit/Dialog","dijit/ProgressBar", "dojo/domReady!"],
function (layout, dom, domAttr) {
mapControl = new layout();
layout.js：
define(["dojo/_base/declare"], function(declare) {
return declare(null, {
action:"pan",
activeMeasureTool:"",
aerialLayer:"",
legendLayers:"",
loadedServices:"",
popup:"",
resizeId:0,
constructor: function() {
this.init();
},
init: function() {
require(["esri/map", "esri/config", "esri/SpatialReference", "esri/geometry/Extent"],
function(Map, config, SpatialReference, Extent) {
//custom map requires a proxy to function properly.
esri.config.defaults.io.proxyUrl = "../sdc_devdata/proxy.php";
var spatRef = new SpatialReference(2276);
var startExtent = new Extent(2481416.32087491, 6963246.42495962, 2501196.36936991, 6980267.92469462, spatRef);
var appFullExtent = new Extent(2396699.46935379, 6872369.60195443, 2607745.94404633, 7107335.22319087, spatRef);
map = new Map("map", {extent: startExtent, isZoomSlider:true, logo:false, sliderStyle:"large"});
this.attachMapEventHandlers();
this.createLayers();
this.handleLayerVisibilityChange();
});
},
您可以将'this'放在另一个变量中，例如_this，并在内部函数中使用_this
init: function() {
var _this= this;
require(["esri/map", "esri/config", "esri/SpatialReference", "esri/geometry/Extent"],
function(Map, config, SpatialReference, Extent) {
...
_this.attachMapEventHandlers();
_this.createLayers();
_this.handleLayerVisibilityChange();
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