ExtReact Docs Help

Introduction

The documentation for the ExtReact product diverges somewhat from the documentation of other Sencha products. The sections below describe documentation for all products except where indicated as unique to ExtReact.

Terms, Icons, and Labels

Many classes have shortcut names used when creating (instantiating) a class with a configuration object. The shortcut name is referred to as an alias (or xtype if the class extends Ext.Component). The alias/xtype is listed next to the class name of applicable classes for quick reference.

ExtReact component classes list the configurable name prominently at the top of the API class doc followed by the fully-qualified class name.

Access Levels

Framework classes or their members may be specified as private or protected. Else, the class / member is public. Public, protected, and private are access descriptors used to convey how and when the class or class member should be used.

Member Types

Member Syntax

Below is an example class member that we can disect to show the syntax of a class member (the lookupComponent method as viewed from the Ext.button.Button class in this case).

lookupComponent ( item ) : Ext.Component
protected

Called when a raw config object is added to this container either during initialization of the items config, or when new items are added), or {@link #insert inserted.

This method converts the passed object into an instanced child component.

This may be overridden in subclasses when special processing needs to be applied to child creation.

Parameters

item :  Object

The config object being added.

Returns
Ext.Component

The component to be added.

Let's look at each part of the member row:

Member Flags

The API documentation uses a number of flags to further commnicate the class member's function and intent. The label may be represented by a text label, an abbreviation, or an icon.

Class Icons

- Indicates a framework class

- A singleton framework class. *See the singleton flag for more information

- A component-type framework class (any class within the Ext JS framework that extends Ext.Component)

- Indicates that the class, member, or guide is new in the currently viewed version

Member Icons

- Indicates a class member of type config

Or in the case of an ExtReact component class this indicates a member of type prop

- Indicates a class member of type property

- Indicates a class member of type method

- Indicates a class member of type event

- Indicates a class member of type theme variable

- Indicates a class member of type theme mixin

- Indicates that the class, member, or guide is new in the currently viewed version

Class Member Quick-Nav Menu

Just below the class name on an API doc page is a row of buttons corresponding to the types of members owned by the current class. Each button shows a count of members by type (this count is updated as filters are applied). Clicking the button will navigate you to that member section. Hovering over the member-type button will reveal a popup menu of all members of that type for quick navigation.

Getter and Setter Methods

Getting and setter methods that correlate to a class config option will show up in the methods section as well as in the configs section of both the API doc and the member-type menus just beneath the config they work with. The getter and setter method documentation will be found in the config row for easy reference.

ExtReact component classes do not hoist the getter / setter methods into the prop. All methods will be described in the Methods section

History Bar

Your page history is kept in localstorage and displayed (using the available real estate) just below the top title bar. By default, the only search results shown are the pages matching the product / version you're currently viewing. You can expand what is displayed by clicking on the button on the right-hand side of the history bar and choosing the "All" radio option. This will show all recent pages in the history bar for all products / versions.

Within the history config menu you will also see a listing of your recent page visits. The results are filtered by the "Current Product / Version" and "All" radio options. Clicking on the button will clear the history bar as well as the history kept in local storage.

If "All" is selected in the history config menu the checkbox option for "Show product details in the history bar" will be enabled. When checked, the product/version for each historic page will show alongside the page name in the history bar. Hovering the cursor over the page names in the history bar will also show the product/version as a tooltip.

Search and Filters

Both API docs and guides can be searched for using the search field at the top of the page.

On API doc pages there is also a filter input field that filters the member rows using the filter string. In addition to filtering by string you can filter the class members by access level, inheritance, and read only. This is done using the checkboxes at the top of the page.

The checkbox at the bottom of the API class navigation tree filters the class list to include or exclude private classes.

Clicking on an empty search field will show your last 10 searches for quick navigation.

API Doc Class Metadata

Each API doc page (with the exception of Javascript primitives pages) has a menu view of metadata relating to that class. This metadata view will have one or more of the following:

Expanding and Collapsing Examples and Class Members

Runnable examples (Fiddles) are expanded on a page by default. You can collapse and expand example code blocks individually using the arrow on the top-left of the code block. You can also toggle the collapse state of all examples using the toggle button on the top-right of the page. The toggle-all state will be remembered between page loads.

Class members are collapsed on a page by default. You can expand and collapse members using the arrow icon on the left of the member row or globally using the expand / collapse all toggle button top-right.

Desktop -vs- Mobile View

Viewing the docs on narrower screens or browsers will result in a view optimized for a smaller form factor. The primary differences between the desktop and "mobile" view are:

Viewing the Class Source

The class source can be viewed by clicking on the class name at the top of an API doc page. The source for class members can be viewed by clicking on the "view source" link on the right-hand side of the member row.

ExtReact 6.5.1


top

Ext.dom.Helper singleton

NPM Package

@extjs/ext-react

Hierarchy

Ext.Base
Ext.dom.Helper

Summary

The DomHelper class provides a layer of abstraction from DOM and transparently supports creating elements via DOM or using HTML fragments. It also has the ability to create HTML fragment templates from your DOM building code.

DomHelper element specification object

A specification object is used when creating elements. Attributes of this object are assumed to be element attributes, except for 4 special attributes:

  • tag: The tag name of the element
  • children (or cn): An array of the same kind of element definition objects to be created and appended. These can be nested as deep as you want.
  • cls: The class attribute of the element. This will end up being either the "class" attribute on a HTML fragment or className for a DOM node, depending on whether DomHelper is using fragments or DOM.
  • html: The innerHTML for the element

Insertion methods

Commonly used insertion methods:

Example

This is an example, where an unordered list with 3 children items is appended to an existing element with id 'my-div':

var dh = Ext.DomHelper; // create shorthand alias
// specification object
var spec = {
    id: 'my-ul',
    tag: 'ul',
    cls: 'my-list',
    // append children after creating
    children: [     // may also specify 'cn' instead of 'children'
        {tag: 'li', id: 'item0', html: 'List Item 0'},
        {tag: 'li', id: 'item1', html: 'List Item 1'},
        {tag: 'li', id: 'item2', html: 'List Item 2'}
    ]
};
var list = dh.append(
    'my-div', // the context element 'my-div' can either be the id or the actual node
    spec      // the specification object
);

Element creation specification parameters in this class may also be passed as an Array of specification objects. This can be used to insert multiple sibling nodes into an existing container very efficiently. For example, to add more list items to the example above:

dh.append('my-ul', [
    {tag: 'li', id: 'item3', html: 'List Item 3'},
    {tag: 'li', id: 'item4', html: 'List Item 4'}
]);

Templating

The real power is in the built-in templating. Instead of creating or appending any elements, createTemplate returns a Template object which can be used over and over to insert new elements. Revisiting the example above, we could utilize templating this time:

// create the node
var list = dh.append('my-div', {tag: 'ul', cls: 'my-list'});
// get template
var tpl = dh.createTemplate({tag: 'li', id: 'item{0}', html: 'List Item {0}'});

for(var i = 0; i < 5; i++){
    tpl.append(list, i); // use template to append to the actual node
}

An example using a template:

var html = '"{0}" href="{1}" class="nav">{2}';

var tpl = new Ext.DomHelper.createTemplate(html);
tpl.append('blog-roll', ['link1', 'http://www.foxmulder.com/', "Fox's Site"]);
tpl.append('blog-roll', ['link2', 'http://www.danascully.org/', "Scully's Site"]);

The same example using named parameters:

var html = '"{id}" href="{url}" class="nav">{text}';

var tpl = new Ext.DomHelper.createTemplate(html);
tpl.append('blog-roll', {
    id: 'link1',
    url: 'http://www.danascully.org/',
    text: "Scully's Site"
});
tpl.append('blog-roll', {
    id: 'link2',
    url: 'http://www.foxmulder.com/',
    text: "Fox's Site"
});

Compiling Templates

Templates are applied using regular expressions. The performance is great, but if you are adding a bunch of DOM elements using the same template, you can increase performance even further by "compiling" the template. The way "compile()" works is the template is parsed and broken up at the different variable points and a dynamic function is created and eval'ed. The generated function performs string concatenation of these parts and the passed variables instead of using regular expressions.

var html = '"{id}" href="{url}" class="nav">{text}';

var tpl = new Ext.DomHelper.createTemplate(html);
tpl.compile();

// ... use template like normal

Performance Boost

DomHelper will transparently create HTML fragments when it can. Using HTML fragments instead of DOM can significantly boost performance.

Element creation specification parameters may also be strings which are used as innerHTML.

No members found using the current filters

properties

methods

Static Methods

override ( members ) : Ext.Base
static sta

Override members of this class. Overridden methods can be invoked via Ext.Base#callParent.

Ext.define('My.Cat', {
    constructor: function() {
        alert("I'm a cat!");
    }
});

My.Cat.override({
    constructor: function() {
        alert("I'm going to be a cat!");

        this.callParent(arguments);

        alert("Meeeeoooowwww");
    }
});

var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
                          // alerts "I'm a cat!"
                          // alerts "Meeeeoooowwww"

Direct use of this method should be rare. Use Ext.define instead:

Ext.define('My.CatOverride', {
    override: 'My.Cat',
    constructor: function() {
        alert("I'm going to be a cat!");

        this.callParent(arguments);

        alert("Meeeeoooowwww");
    }
});

The above accomplishes the same result but can be managed by the Ext.Loader which can properly order the override and its target class and the build process can determine whether the override is needed based on the required state of the target class (My.Cat).

Parameters

members :  Object

The properties to add to this class. This should be specified as an object literal containing one or more properties.

Returns

:Ext.Base

this class

ExtReact 6.5.1