Is there a way to preload templates when using AngularJS routing? - angularjs

Question

After the Angular app is loaded I need some of the templates to be available offline.
Something like this would be ideal:
$routeProvider
.when('/p1', {
controller: controller1,
templateUrl: 'Template1.html',
preload: true
})

Answer 1

This is an addition to the answer by #gargc.
If you don't want to use the script tag to specify your template, and want to load templates from files, you can do something like this:
myApp.run(function ($templateCache, $http) {
$http.get('Template1.html', { cache: $templateCache });
});
myApp.config(function ($locationProvider, $routeProvider) {
$routeProvider.when('/p1', { templateUrl: 'Template1.html' })
});

Answer 2

There is a template cache service: $templateCache which can be used to preload templates in a javascript module.
For example, taken from the docs:
var myApp = angular.module('myApp', []);
myApp.run(function($templateCache) {
$templateCache.put('templateId.html', 'This is the content of the template');
});
There is even a grunt task to pre-generate a javascript module from html files: grunt-angular-templates
Another way, perhaps less flexible, is using inline templates, for example, having a script tag like this in your index.html:
<script type="text/ng-template" id="templates/Template1.html">template content</script>
means that the template can be addressed later in the same way as a real url in your route configuration (templateUrl: 'templates/Template1.html')

Answer 3

I think I have a slightly improved solution to this problem based on Raman Savitski's approach, but it loads the templates selectively. It actually allows for the original syntax that was asked for like this:
$routeProvider.when('/p1', { controller: controller1, templateUrl: 'Template1.html', preload: true })
This allows you to just decorate your route and not have to worry about updating another preloading configuration somewhere else.
Here is the code that runs on start:
angular.module('MyApp', []).run([
'$route', '$templateCache', '$http', (function ($route, $templateCache, $http) {
var url;
for (var i in $route.routes) {
if ($route.routes[i].preload) {
if (url = $route.routes[i].templateUrl) {
$http.get(url, { cache: $templateCache });
}
}
}
})
]);

Answer 4

Preloads all templates defined in module routes.
angular.module('MyApp', [])
.run(function ($templateCache, $route, $http) {
var url;
for(var i in $route.routes)
{
if (url = $route.routes[i].templateUrl)
{
$http.get(url, {cache: $templateCache});
}
}
})

Answer 5

if you wrap each template in a script tag, eg:
<script id="about.html" type="text/ng-template">
<div>
<h3>About</h3>
This is the About page
Its cool!
</div>
</script>
Concatenate all templates into 1 big file. If using Visual Studio 2013,Download Web essentials - it adds a right click menu to create an HTML Bundle
Add the code that this guy wrote to change the angular $templatecache service - its only a small piece of code and it works :-)
https://gist.github.com/vojtajina/3354046
Your routes templateUrl should look like this:
$routeProvider.when(
"/about", {
controller: "",
templateUrl: "about.html"
}
);