还有一个使用 $route.resolve 和 promises 的选项。这将等到 CSS 实际加载后,不仅添加到头部(之后浏览器才开始检索文件,并且根据 CSS 大小可能会导致页面重排)。
// Routing setup
.config(function ($routeProvider) {
$routeProvider
.when('/home', {
controller: 'homeCtrl',
templateUrl: 'home.tpl.html'
}).when('/users', {
controller: 'usersCtrl',
controllerAs: 'vm',
templateUrl: 'users.tpl.html',
resolve: {
load: ['injectCSS', function (injectCSS) {
return injectCSS.set("users", "users.css");
}]
}
}).otherwise({
// default page
redirectTo: '/home'
});
})
服务实施
.factory("injectCSS", ['$q', '$http', 'MeasurementsService', function($q, $http, MeasurementsService){
var injectCSS = {};
var createLink = function(id, url) {
var link = document.createElement('link');
link.id = id;
link.rel = "stylesheet";
link.type = "text/css";
link.href = url;
return link;
}
var checkLoaded = function (url, deferred, tries) {
for (var i in document.styleSheets) {
var href = document.styleSheets[i].href || "";
if (href.split("/").slice(-1).join() === url) {
deferred.resolve();
return;
}
}
tries++;
setTimeout(function(){checkLoaded(url, deferred, tries);}, 50);
};
injectCSS.set = function(id, url){
var tries = 0,
deferred = $q.defer(),
link;
if(!angular.element('link#' + id).length) {
link = createLink(id, url);
link.onload = deferred.resolve;
angular.element('head').append(link);
}
checkLoaded(url, deferred, tries);
return deferred.promise;
};
return injectCSS;
}])
如果这是您想要包含的内容,您可以使用尝试添加超时。
查看这篇文章了解更多详情:https ://medium.com/angularjs-meetup-south-london/angular-dynamically-injecting-css-file-using-route-resolve-and-promises-7bfcb8ccd05b