I am currently using the ui/builder to load a component with an xml and js file like this:
let component = builder.load({
path: 'pages/path/to/component',
name: 'component'
});
I then add the component to an existing view. This all works fine, but I am actually calling this up to hundreds of times because the parent contains many of these components (similar to a repeater containing a lot of items). Does the builder.load method need to be called every time with the path to the xml/js files, or can the in-memory component be duplicated? Would there be a performance benefit to doing things this way, or does the nativescript builder already keep a cache of referenced components?
It could be a performance hit as the builder will parse the XML every time to create the JavaScript instance, you may keep a reference to the returned component after first call to builder.
But it could be still a performance hit as you are going to load 100s of components. You must consider using ListView that recycles the unused views as needed.
If you use builder / repeater, you are actually creating 100s of elements on screen, when ListView is used it creates only elements those are visible on screen. As you scroll down or up, it is going to reuse the elements those are off screen that improves the performance a lot.
Related
I'd like to use Nightwatch's Page Objects system for UI components used across our app. Because nightwatch has their own way of reading/initializing them, I don't see a way of properly extending/re-using them.
For example I want an DateInputPageObject for "date fields". It would identify the label, input, date picker, etc.
I'd use it on any page with a date input field.
I would also like to extend page objects. For example, class FooModal extends Modal. The ModalPageObject would define selectors for elements all modals have - the overlay, container, close button, etc.
I can't find any way to do this in nightwatch, is it possible at all?
The problem is not with nightwatch per se as it's just following the basic structure of page object model BUT that is a very good question and it brings out one of the drawbacks of page object model.
Page object model has been around for some time and the problem with that is that it doesn't serve the needs of modern web applications that use component libraries & living style-guides and re-using components.
Personally I found it easier to use a global json file with all the components structured based on their type. e.g. labels, fields, buttons, etc.
I'm newest in web.
I want customize default scroll-bar in ag-grid. I try use ngx-scrollbar for this. In sources ngx-scrollbar I found that ngx-scrollbar using ng-content for wrapping elements(link to github source file). If wrap ag-grid-angular element then scrolling even doesn't shows because content doesn't overflow ag-grid-angular content because oveflow happen in div with class .ag-body-viewport where using stock srolls. In order to achieve needed effect I wish pass DOM element with class .ag-body-viewport to ng-content of ngx-scrollbar. Is it possible?
More info here github issue but I don't use Nice Scroll or Perfect Scrollbar
I want use ngx-scrollbar because it has capability of customization.
UPDATE
I can pass DOM element to ng-content using next sintax(agGridViewport is native element):
<ng-scrollbar>
{{ agGridViewport }}
<ng-scrollbar>
but it pass element like a copy of real DOM object but I want pass this like a refence.
Now I got UI like a stack style:
[rendered real ag-grid-angular]
[rendered ng-scrollbar with his content]
But it isn't that I need. Also I got bad rendering with artifacts and even some components doesn't appear. Now I want to try use Renderer2 for putting ng-scrollbar element between two DOM elements in tree(.ag-body-viewport-wrapper and .ag-body-viewport). But I think it's very bad idea because Renderer2 doesn't have methods for putting elements between DOM elements in tree and my code will be very unlify and complicated :( It's must be like injection.
No, I can not do injection in DOM with Angular tools. It's bad idea do it and it is not possible now. AgGrid doesn't support customization with tools like ngx-scrollbar which using ng-content for wrapping components and other elements. May be better way using other tools which working by another way or using webkit customization which supports not all web browsers.
UPDATE
Also I try to use smooth-scrollbar. I managed to get better result. I bind him to element .ag-body-viewport. It works fine but it scrolling only content of grid without header be careful. smooth-scroll bar doesn't have options for horizontal and vertical scrollbar as a different units. I know how issue can be solve. Vertical scrollbar must be bind to .ag-body-viewport and horizaontal scrollbar must be bind to .ag-root. If your can find scrollbar which let you do it that you can solve this problem. May be I write special component for Angular in near future and then add link to this answer. If you do it faster you can add yourself link or you can add link to already existing packages.
I have an application where I need to display metrics. The application needs to display a separate vertical section for each metric. When I started this, there were only 5 metrics so I naively created a template with 5 regions, one for each metric I needed to display. Now, new metrics need to be added and I want to avoid adding "hardcoded" region divs in the template. I want to refactor this and create the required regions dynamically at startup time based on some configuration data.
So I have been looking at the latest Marionette release and in question "Dynamically add regions to Marionette layout", Derick Bailey mentions that Marionette v1.0 supports dynamic regions in Layouts through addRegion(), as in:
var layout = new MyLayout();
layout.render()
layout.addRegion("someRegion", "#some-element");
layout.someRegion.show(new MyView());
I have tried that in my code (using Marionette 1.0.2) and I am not getting it to work. I don't have a div with id="some-element" in my template and I suspect this could be the reason. I was hoping that Marionette would create that div itself.
Perhaps my expectation of what dynamically adding a region means is wrong. So my first question is: when adding regions dynamically to a layout, must the element id passed in the addRegion() function already exist in the layout?
If so, then I am back to the problem of having to "burn" in the template those divs for the regions to attach themselves too. My follow-up question is then: What is the best way of doing this in a data-driven fashion? Is it a matter of writing my own render() function so that the right set of divs get created? Or perhaps providing my Layout with a model object that will contain data which the template can then iterate through to create the necessary divs? How do we add regions dynamically to a Layout object if we don't know in advance how many regions we will actually need?
Aa #aaronfay specified, we need to use jQuery to create the element on the page. Here is some sample code:
var layout = new MyLayout();
layout.render()
var regionName = "dynamicRegion";
layout.$el.append('<div id="'+regionName+'"></div>');
layout.addRegion("someRegion", "#"+regionName);
layout.someRegion.show(new MyView());
I believe you would need to use jQuery (or similar) to create the element on the page. A Region expects the element to exist.
Otherwise, I believe your answer is here.
Currently, in our deployment we have a abstract type Component which represents a part of our Page, basically an element such as a Question, which can have multiple choice, a text box or any other form of answering it, or a Video that users can play, basically a shard of a page that is interchangeable, basically, our design was to have a specific area in our website which would be rendered through a list of Components, we tried at first to have each "Page" object have a List of Components, and each Component would have a method render that would return a Spring View, we thought we could iterate over the list and somehow mash the views together.
We also tried using XSTLViews with no more success, it seems to be more of a design problem and our abuse of the way Spring MVC should be used.
We will really be glad to receive any advice/tips/corrections about how to do it right and maybe some corrections about misconceptions we might have.
It sounds like you're more than half way to a design that uses AJAX to build your page. You're trying to mash up a bunch of Components into one request. What if you returned a container page which then requested/inserted a block of html for each URL it was given a render time. Each of these URLs would refer to a single component. It might be a performance hit if you are including a lot of these Components, but it seems to fit the design.
I sometimes get messed up by the three rendering methods:
Controller::render()
Controller::renderPartial()
Controller::renderFile()
Please could you explain. Thank you!
render() is commonly used to render a view that corresponds to what a user sees as a "page" in your application. It first renders the view you have specified and then renders the layout for the current controller action (if applicable), placing the result of the first render into the layout. It then performs output processing (which at this time means automatically inserting any necessary <script> tags and updating dynamic content) and finally outputs the result.
renderPartial() is commonly used to render a "piece" of a page. The main difference from render() is that this method does not place the results of the render in a layout. By default it also does not perform output processing, but you can override this behavior using the $processOutput parameter.
renderFile() is a low-level method that does the grunt work of rendering: it extracts the data variables in the current scope and then runs the view code. The other two methods internally call this one, but you should practically never need to call it yourself. If you do, keep in mind that you need to pass in a file path (not a view path).
Render File:
Will run the rendering methods on a given file with the set rendering engine. This is fairly low level within Yii and only really used internally or in console commands.
Render Partial:
This takes the alias given and converts it into a file path using all the local variables such as current running controllers and modules and alias definitions. It then pretty much just uses render file.
Render:
This is combination of render partials to make our lives easier. It will render the layout on the currently active contoller, or the defined one, render all the content within it, handle caching of renders, and process the output for client scripts.
Hope that clears it up.
renderPartial() is really useful for displaying ssi components in a page - ie, headers, footers, widgets etc.