Adding html elements to page with MVC Razor pages - html

On the html for my page I have a <script id="pagedata"></script> element which I would like to add an element to only if a certain partial is rendered. In my layout.cshtml I have the following:
#if (Brand != null)
{
#Html.Partial("_UseApp");
}
And in my _UseApp.cshtml:
#{
var iosAppUrl = // retrieve iosLink from our CRM database
var androidUrl = // retrieve android link from our CRM database
// Here I want to add the above variables to the <script id=pagedata> in the html page. Something
like this:
PageData.AddPageData("appstore", iosAppUrl);
PageData.AddPageData("playstore", androidUrl);
I cannot work out how to do this - I set breakpoints in the UseApp.cshtml file and the file is being called, but I don't know how to add these script elements. I don't want to just add them into the layout file because I want to keep the app logic separate. Can anyone help? Thanks

My approach to this would be to use jQuery, as reading HTML elements in C# is rather difficult.
In the script below, it checks if the HTML exists, and if it does, we will assign an attribute to it. The second argument in attr() will be your link, note that you can use C# to get the value from your Db, by using the model or ViewBag.
#section Scripts{
<script>
$(document).ready(function () { // on ready
if ($("#replaceWithYourId").length) { // check if ID exists
$("#pagedata").attr("data-playstore", "link") // use jQuery attr method.
}
});
</script>
}

Related

Conditionally adding tags options parameter to select2

I have multiple elements on a page that are triggering a load of select2 to the element. I'm trying to conditionally check if the element has a certain class, and if so add the tag option; otherwise do not. I thought something like this would work, but it's not:
$('.element_to_add_select_two_on').select2({
tags:function(element) {
return (element.className === 'classname_i_am_targeting');
},
});
What am I missing here? I'm subjecting myself to the following buffoonery to get this to target and load:
$('.element_to_add_select_two_on').each((index,element) => {
let showTags = false;
if ($(element).attr('class').split(' ').includes('classname_i_am_targeting')) {
showTags = true;
}
$(element).select2({
tags:showTags,
});
});
There are a few problems with your first attempt. First, you are defining tags as a function when what you want is the result of the function, since tags needs to be defined as a boolean true or false. The other is that inside your .select2() call, you do not have access to the calling element $('.element_to_add_select_two_on') in the way that you think. It isn't an event that you are listening on, it's a function call that wants an object passed with its configuration.
You conveyed that your second method works, but it can be simplified with the jQuery hasClass() function:
$('.element_to_add_select_two_on').each((index, element) => {
$(element).select2({
tags: $(element).hasClass('classname_i_am_targeting'),
});
});
There is a much simpler way to do all of this, however, and it is much more flexible and already built into select2 via the way of data-* attributes (note, you need jQuery > 1.x). You can simply add data-tags="true" to any of your select elements with which you want tags enabled. These will override any configuration options used when initializing select2 as well as any defaults:
<select data-tags="true">
...
</select>

VAADIN - Button | implement in HTML Layout-Script

is there any oportnunity to use a Vaadin Button in a HTML script?
Id like to use the following button
Button button_login = ew Button();
button_login.setID("buttonlogin");
and this button should be implement in the following script
<div data-location="buttonlogin"></div>
(Only an idea)
Have so. an idea to bind the button in the html script?
Thank!
I am quite unsure what you mean by html script. If it is something you can achieve using JavaScript then here is my try.
Generally to execute JavaScript on button click
Button js = new Button("Do JavaScript");
js.addClickListener( click -> {
com.vaadin.ui.JavaScript.getCurrent().execute("alert(´Hello´)");
});
When in need to use external .js files, for example hello.js, contents below
function hello() {
alert("Hello JavaScriptWorld!");
}
Assuming hello.js is directly under /VAADIN/ directory, add following annotation to your UI or relevant component class
#JavaScript({"vaadin://hello.js"}) // all paths must be relative to /VAADIN
Then in ClickListener you can refer to function hello() like
com.vaadin.ui.JavaScript.getCurrent().execute("hello()");
Java
#com.vaadin.annotations.JavaScript("vaadin://themes/paastheme/layouts/ui/donut/donut.js")
public class BrowsePeopleUI extends UI {}
I put JS file to:
src/main/resources/VAADIN/themes/paastheme/layouts/ui/donut/donut.js
My donut.js is:
Javascript
var util = util || {};
util.donut = () => {console.log(document.querySelectorAll("[data-svg]"))};

html5 template tag: fallback for content access

I am using a template tag in a webkit browser (JavaFX WebView 2.2) to store elements that I may clone and append on the main part of the document.
However, I can't access its content using templateElement.content (the HTML5 standard). Instead, I use jQuery to get the elements inside the template TAG with the selector "#templateElement div".
Seems the template tag is not yet fully supported (inner scripts also run), although its contents are not rendered.
My fear is that, when the template tag becomes supported, the way to get its contents will break and my page will stop working.
What is the recommended way of getting template contents regardless future implementation changes?
HTML:
<template id="templateElement">
<div>Clone Me!</div>
</template>
JavaScript:
function getContentsCurrent() {
var toBeCloned = $("#templateElement div")[0];
//append where needed...
}
function getContentsFuture() {
var toBeCloned = templateElement.content.getElementsByTagName("div")[0];
//append where needed...
}
EDIT
I think jQuery won't be able to handle this automatically, even in the future, because the template "innerHTML" is purposely routed to content so that it becomes inaccessible to the DOM (so no selector touches it accidentally).
You could test if the content feature exists before:
function getContents() {
var toBeCloned;
if ( templateElement.content )
toBeCloned = templateElement.content.getElementsByTagName("div")[0];
else
toBeCloned = templateElement.querySelector("div");
//append where needed...
}
Another way:
var content = templateElement.content || templateElement
var toBeCloned = content.querySelector( "div" )
//...

Cannot select elements inside "auto-binding" template

I have created some custom elements, now I'm writing tests for them.
I wanted to use "auto-binding" because I have plenty of attributes that needs to be bound among my elements.
Unfortunately I cannot query any element inside the template.
Here is some code.
<template id="root" is="auto-binding">
<dalilak-data-service id="dds" regions="{{regions}}"></dalilak-data-service>
<dalilak-regions-handler id="drh" regions="{{regions}}" flattendedRegions="{{flattendRegions}}" descendantsRegionNames="{{descendantsRegionNames}}" regionsByNameId="{{regionsByNameId}}"></dalilak-regions-handler>
</template>
In the test script I have tried the following
drh = document.querySelector('#drh');
suite('dalilak-regions-handler', function() {
test('handler initialized', function() {
assert.ok(drh);
});
});
Also tried this:
drh = document.querySelector('* /deep/ #drh'); // or '#root /deep/ #drh'
suite('dalilak-regions-handler', function() {
test('handler initialized', function() {
assert.ok(drh);
});
});
But none of them worked.
Note without the template I can query my custom elements.
auto-binding templates stamp asynchronously, I expect your problem is that you need to wait for the template to stamp before querying for elements.
The template fires a template-bound event when this happens, so you can use code like this:
addEventListener('template-bound', function() {
drh = document.querySelector('#drh');
...
});
Of course, this means your testing infrastructure will need to understand how to handle asynchrony, which can be a concern.
Where possible, it is best to avoid the /deep/ selector. That is a nuclear option and can return unexpected results because it pierces all shadow DOMs. It also won't work for your auto-binding template because its contents are inside a #document-fragment, not a #shadow-root. Instead, try querying the #document-fragment itself. This preferable because you are limiting your query to the scope of your template, which is much more precise.
var template = document.querySelector('#root');
var drh = template.content.querySelector('#drh');

jqPlot charts on page load

I have a form where I select the number of items. Upon clicking submit, it should take me to a new page where it would display the item selected and depending on the number of items selected, it would create those many jqPlots, one for each item.
Any suggestions on how do I go about doing this?
Thanks,
S.
It's hard to give any specifics without more detail about the items, but basically you would pass a JSON structure to your view with the items to be plotted. Then you would loop through the JSON structure, creating DIV tag for each item to be plotted and appending the DIV tags to the body.
The Javascript part would look something like this:
$.each(items, function(index, value) {
$myPlot = $("<div>");
$myPlot.attr("id", "item"+index);
$.jqplot($myPlot.attr("id"), ...);
$("body").append($myPlot);
});
This question is very general, but answering (specifically and only) the question of loading multiple charts:
You need a unique HTML div id for each chart; consider using an RFC 4122 UUID (generate as needed) for each chart/div rather than a sequential index for each. Use something that looks like this as a placeholder div for each:
<div class="chartdiv" id="chartdiv-${UID}">
<a rel="api" type="application/json" href="${JSON_URL}" style="display:none">Data</a>
</div>
This embeds the JSON URL for each div inside it, in a hidden hyperlink that can be discovered by JavaScript iterating over your multi-chart HTML page.
The matter of the UUID is inconsequential -- it just seems the most robust way to guarantee a unique HTML id addressable by JavaScript for each chart.
Subsequently, you should have JavaScript that looks something like:
jq('document').ready(function(){
jq('.chartdiv').each(function(index) {
var div = jq(this);
var json_url = jq('a[type="application/json"]', div).attr('href');
var divid = div.attr('id');
jq.ajax({
url: json_url,
success: function(responseText) { /*callback*/
// TODO: responseText is JSON, use it, normalize it, whatever!
var chartdata = responseText;
jq.jqplot(divid, chartdata.seriesdata, chartdata.options);
}
});
});
});