doc_server

EXC | DEV | Documentation | Version 1.0

Views

This topic applies to the BackEnd framework.
File: /server/excviews.php

A view is used to build your user interface. In EXC we can manipulate views from the server side prior to serving the content to the browser or dynamically in the front-end.

A view is a php file named view.myname.php, where myname is the actual name of your view.

NOTE: The view can be an HTML file like view.myname.html.

You place your view files in a folder named views in your app folder. This is where EXC would look for them by default.

### Creating a view ### {#createview}

A view file contains the actual HTML code, it is our template, like for example:

<!doctype html>
<html>
<head>
	<title>{{title}}</title>
</head>
<body class='layout'>
Hello {{username}}...<br>
{{contents}}
</body>
</html>

You can add value placeholders that you replace from PHP. For example a placeholder for a "username" is defined as {{username}}.

In the example above we have the placeholders {{username}}, {{contents}} and {{title}}.

## Using placeholders ## {#placeholders}

In PHP we set the value of a placeholder with the set($html) method:

<?php
$username = "supercoolcat99";
$view->username->set($username);

You can append to a placeholder with the write($html) method:

<?php
$view->contents->write($someHTML);
$view->contents->write($moreHTML);

### Beyond placeholders ### {#bplaceholders}

You can set values that can be used as placeholders in all your views using a @CONSTANT.

You can add a constant value in PHP like this:

$location = 'RUM';
\exc\ui\views\view::constantSetValue("location", $location);

In your view file a constant placeholder is available as:

{{@location}}

Special framework values are available as @CONTANTS in your view file.

NAME	DESCRIPTION
@URL_BASE	URL path of your app.
@URL_CONTROLLER_DIRECTORY	URL path to the folder with current controller.
@URL_CONTROLLER	URL pointing to the current controller.
@BASE	Path of your app.
@CONTROLLER_DIRECTORY	Path to the folder with current controller.

## Using directives ## {#usingdirec}

Directives are another type of placeholders that make your view more flexible.

### view directive ## {#dirview} Use the #view directive to include the contents of another view:

{{#view record_header}}

### file directive ## {#dirfile} Use the #file directive to include a file:

{{#file /absolute/path/file.js}}

You can use exc's special url protocols with #file, for example asset://, file://, app://, and exc://:

{{#file asset://header.html}}

Similar to the file #file directive you have the short hands #script and #style directives. Each will place the contents of the file in a corresponding <script> or <style> tag.

{{#script asset://js/myscript.js}}

### if directive ## {#dirif} The #if directive will include its contents when the value of a variable evaluates to true.

{{#if ind_new_account}}
	<b>Welcome to EXC...</b>
{{end if ind_new_account}}

### inherits directive ## {#dirinherits} Use the #inherits directive to make a view that is based on another template. This is useful to avoid duplicating content. An inherits directive should be the first line of your view template. Lets see an example:

{{#inherits default {{body}} }}

The first argument of this directive is the name of a view file that will be used as template. In this example is default for the file view.default.php.

The second argument is a placeholder in that view file where the current view will be injected. In this example the contents of our view are displayed inside the placeholder {{body}}.

Placing views in other locations

In many instances you may want to place your views in another folder or even share views between apps.

You can tell EXC where to look for views in your app definition using the option $options['views.paths']. Set $options['views.paths'] to a string with the path to a folder with your views.

$options['views.paths'] = '../employee_common/views/';

NOTE: A path can be an absolute path or relative to your application.

You can also use an array with multiple paths as needed:

<?php
$options['views.paths'] = [
	'../employee_common/views/',
	'/Library/WebServer/Documents/examples/shared/views/',
];