在什么情况下可以解决承诺而不是火灾回调？
这里我已经分配了这个承诺，我正在记录一个临时的全局变量temp1。如您所见，当我输出temp1的状态时，它返回resolved。然而，当我将done处理程序附加到temp1时，它永远不会触发。
temp1是指$.Deferred，但我也尝试使用temp1.promise().done()，但无济于事。
我做错了什么？
pv5.widgets = new function () {
/**
* @var array _widget_queue A map of widget IDs to promises that are resolved
* when they are loaded
*/
this._widget_queue = [];
/**
* @var array _js_queue A map of JavaScript dependency names to promises that
* are resolved when they are loaded
*/
this._js_queue = [];
/**
* Loads the HTML into the widget's container
* @param object w The widget implementation in pv5.widgets
* @param object widget The widget's configuration data
* @return jQueryPromise A promise that is resolved when the HTML loads
*/
this._get_res = function (w, widget) {
var r = widget.config.res || widget.res;
if (!r) {
return $.Deferred().resolve().promise();
}
typeof r != 'string' && (r = r[pv5.user.auth.role] ? r[pv5.user.auth.role] : 'blank.html');
var path = (widget.product_level || widget.config.product_level ? pv5.widgets._APP_WIDGET_RESOURCE_ROOT : pv5.widgets._WIDGET_RESOURCE_ROOT) + r;
return $.get(path, {_v: pv5._NOCACHE ? new Date().getTime() : ''})
.done(function (html) {
w._owner.html(html + '<div style="clear: both;"></div>');
})
.fail(function () {
console && console.error('Failed to load resource for widget ' + id + '.', arguments);
});
};
/**
* Loads the provided widget and all resources it requires
* @param string id The identifier for the widget
* @param object widgets The widget library map
* @param boolean only_required Only load if it is required
* @return jQueryPromise A promise that resolves when the widget is loaded
*/
this.loadWidget = function (id, widgets, only_required) {
// First, make sure we haven't already started loading it; if we have,
// return the existing promise
var widget_loading = $.inArray(id, $.map(this._widget_queue, function (o) { return o.widget; }));
if (widget_loading > -1) {
return this._widget_queue[widget_loading].promise;
}
// Look in the provided widgets, or merge the registry and activeApp
// widgets if none were provided
widgets = widgets || $.extend({}, pv5.widgets._REGISTRY, pv5.activeApp._WIDGETS, true);
var widget = widgets[id];
// Make sure the widget exists
if (!widget) {
console && console.error('Widget ' + id + ' is not registered in widget library.');
return $.Deferred().reject().promise();
}
// Configure it if it isn't already
if (!widget.configured) {
var configured = $.extend({
_id: id,
required: false,
configured: true,
auth: true,
config: {
required: false,
res: false,
auth: false
}
}, pv5.widgets._REGISTRY[id]);
$.extend(configured.config, widgets[id]);
configured._version = pv5._VERSION + '_' + (configured.version || 0) + '_' + (configured.config.version || 0);
widgets[id] = widget = configured;
}
// Don't load the widget if only_required was passed in and it's not required
// (only_required is used in loadWidgets for page load)
if (only_required && !widget.required && !widget.config.required) {
return $.Deferred().resolve().promise();
}
// Load JavaScript dependencies
if (widget.js || widget.config.js) {
var j = widget.config.js || widget.js;
// Normalize to an array of JavaScript files
typeof j == 'string' && (j = [j]);
j = j || [];
// Create a queue (array of objects with promises)
// For each one, include a full path to the file we need
// The path property is checked to ensure we don't push the same script
// on the queue twice, and finished is just for debugging convenience
// started is checked to see if the script has begun loading
// properties for making debugging easier
// promise is resolved when the script is loaded and it proceeds to the
// next script in the queue
$.map(j, function (script) {
var path = (widget.product_level || widget.config.product_level ? pv5.widgets._APP_WIDGET_JS_ROOT : pv5.widgets._WIDGET_JS_ROOT) + script;
if ($.inArray(path, $.map(pv5.widgets._js_queue, function (o) { return o.path; })) < 0) {
pv5.widgets._js_queue.push({
path: path,
promise: $.Deferred(),
started: false,
finished: false
});
}
});
var load_script = function (index) {
if (index > pv5.widgets._js_queue.length - 1) {
return;
}
var script = pv5.widgets._js_queue[index];
if (!script.started) { // If it hasn't already initiated
script.started = true;
$.getScript(script.path).done(function () {
script.finished = true;
script.promise.resolve();
});
}
script.promise
.done(function () {
load_script(index + 1);
})
.fail(function () {
console && console.error('Failed to load script ' + script.path + '.', arguments);
});
};
load_script(0);
}
// Similar structure for the widget queue
// Queue item is resolved when the widget, all dependencies, and resources are done
this._widget_queue.push({
widget: id,
promise: $.Deferred(),
started: true,
finished: false
});
// Get widget source file
var lib;
if (widget.config.src || widget.src) {
var path = (widget.product_level || widget.config.product_level ? this._APP_WIDGET_ROOT : this._WIDGET_ROOT) + (widget.config.src || widget.src);
lib = $.get(path, {_v: widget._version + (pv5._NOCACHE ? '_' + new Date().getTime() : '')})
} else {
lib = $.Deferred().resolve().promise();
}
// The queue item we created above will resolve when all resources are loaded
// We will return it
var widget_loaded = this._widget_queue[this._widget_queue.length - 1].promise;
// Load the source file before its resources
lib
.done(function () {
// When it's loaded, identify the DOM element (_owner) and also
// add it to the public widgets registry and start to populate it
var w = pv5.widgets[id] = pv5.widgets[id] || {};
w._owner = $(pv5.widgets._WIDGET_DOM_BIND_PREFIX + id).addClass(pv5.user.auth.role);
w._config = widget.config;
// Global events
$.each(['onStart', 'onSetMode', 'onAuthChange'], function (i, event) {
widget[event] && $(document).on('pv5.' + event, $.proxy(widget[event], w));
w[event] && $(document).on('pv5.' + event, $.proxy(w[event], w));
});
// Widget events
$.each(['onHide', 'onShow'], function (i, event) {
widget[event] && w._owner.on('pv5.' + event, $.proxy(widget[event], w));
w[event] && w._owner.on('pv5.' + event, $.proxy(w[event], w));
});
// sync_widgets - Bind another widget to show and hide when this widget is toggled
var sync = widget.config.sync_widgets || widget.sync_widgets;
if (sync && sync.length) {
$.each(sync, function (i, widget) {
w._owner
.on('pv5.onShow', function () { $(pv5.widgets[widget]).show(); })
.on('pv5.onHide', function () { $(pv5.widgets[widget]).hide(); });
});
}
// Check user roles and show or hide content in this widget based on privilege
pv5.widgets._handle_auth(w, widget);
// Create a translate method that runs through the widget's container and
// looks for content that can be replaced with localized content
w.translate = function () {
var _this = this;
$('[data-lang]', _this._owner).each(function () {
var key = $(this).attr('data-lang');
if (key in _this.lang) {
$(this).html(_this.lang[key]);
}
});
_this.onTranslate && _this.onTranslate();
};
// Get the HTML that is dumped into the container
var res = pv5.widgets._get_res(w, widget);
// Get the CSS files and drop them into the <head>
var css = (function () {
var c = widget.config.css || widget.css;
typeof c == 'string' && (c = [c]);
c = c || [];
$.each(c, function (i, stylesheet) {
var path = (widget.product_level || widget.config.product_level ? pv5.widgets._APP_WIDGET_CSS_ROOT : pv5.widgets._WIDGET_CSS_ROOT) + stylesheet;
// Make sure the stylesheet isn't a duplicate
if ($('link[rel="stylesheet"]').filter(function () { return $(this).attr('href').split('?')[0] == path; }).length) {
return true; // continue
}
$('<link>').attr({rel: 'stylesheet', href: path + '?_v=' + (pv5._NOCACHE ? '_' + new Date().getTime() : '')}).appendTo($('head'));
});
return $.Deferred().resolve().promise();
})();
// Load the templates and place them in w.templates object
var templates = (function () {
var t = widget.config.templates || widget.templates;
typeof t == 'string' && (t = [t]);
t = t || [];
if (!t.length) {
return $.Deferred().resolve().promise();
}
w.templates = {};
return $.when.apply($, $.map(t, function (template) {
var path = (widget.product_level || widget.config.product_level ? pv5.widgets._APP_WIDGET_TEMPLATE_ROOT : pv5.widgets._WIDGET_TEMPLATE_ROOT) + template;
return $.get(path, {_v: pv5._NOCACHE ? '_' + new Date().getTime() : ''})
.done(function (html) {
w.templates[template] = html;
})
.fail(function () {
console && console.error('Failed to load widget ' + id + ' template ' + template + '.', arguments);
});
}));
})();
// Load the localized file and drop it into w.lang object
var lang = (function () {
var l = widget.config.has_lang || widget.has_lang;
if (!l) {
return $.Deferred().resolve().promise();
}
var promise = $.Deferred();
var path = (widget.product_level || widget.config.product_level ? pv5.widgets._APP_WIDGET_LANG_ROOT : pv5.widgets._WIDGET_LANG_ROOT) + id + '/' + (pv5.user.lang || 'en') + '.json';
$.get(path, {_v: pv5._NOCACHE ? '_' + new Date().getTime() : ''})
.done(function (lang) {
var done = function () {
$('html').attr('lang', pv5.user.lang || 'en');
w.translate();
};
w.lang = lang;
// Merge the platform-level localization with product-level localization
// if such a thing exists -- this can be used to selectively override global
// language parameters with product-specific ones, e.g. "Welcome" to
// "Welcome to CFAexcel"
if (widget.merge_product_lang || widget.config.merge_product_lang) {
var path = pv5.widgets._APP_WIDGET_LANG_ROOT + id + '/' + (pv5.user.lang || 'en') + '.json';
$.get(path, {_v: pv5._NOCACHE ? '_' + new Date().getTime() : ''})
.done(function (lang) {
w.lang = $.extend({}, w.lang, lang);
done();
})
.fail(function () {
console && console.error('Failed to load widget ' + id + ' platform-level language file ' + (pv5.user.lang || 'en') + '.', arguments);
done();
});
} else {
done();
}
promise.resolve();
})
.fail(function () {
w.lang = {};
console && console.error('Failed to load widget ' + id + ' language file ' + (pv5.user.lang || 'en') + '.', arguments);
promise.resolve();
});
return promise;
})();
// Recover the item in the queue that refers to this widget
var queue_item = pv5.widgets._widget_queue[$.inArray(id, $.map(pv5.widgets._widget_queue, function (o) { return o.widget; }))];
// Resolve and init when HTML, CSS, templates, language, and all JavaScript dependencies have loaded
$.when.apply($, [res, css, templates, lang].concat($.map(pv5.widgets._js_queue, function (o) { return o.promise; }))).done(function () {
queue_item.promise.resolve();
queue_item.finished = true;
w.init && w.init(w._config);
});
})
.fail(function () {
console && console.error('Failed to load widget ' + id + ' lib at ' + path + '.', arguments);
});
return widget_loaded;
};
};
当已经加载了给定的窗口小部件时，它是从pv5.widgets.loadWidget(widget_name)返回的承诺。
1 个答案:
答案 0 :(得分：1)
直接回答您的问题：
var d = $.Deferred().reject(); // create an empty rejected promise
d.state = function(){ return "resolved"; }; // override `state`
d.promise().done(function(){
// without any more quirky stuff - this will never run.
})
除了那些和类似的肮脏技巧，pretty much never。
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