    ContainerLayout
      FitLayout
        CardLayout

# Class Ext.layout.CardLayout

Package: | Ext.layout
Defined In: | CardLayout.js
Class: | CardLayout
Extends: | FitLayout

This layout manages multiple child Components, each fitted to the Container, where only a single child Component can be visible at any given time. This layout style is most commonly used for wizards, tab implementations, etc. This class is intended to be extended or created via the layout:'card' Ext.Container.layout config, and should generally not need to be created directly via the new keyword.

The CardLayout's focal method is setActiveItem. Since only one panel is displayed at a time, the only way to move from one Component to the next is by calling setActiveItem, passing the id or index of the next panel to display. The layout itself does not provide a user interface for handling this navigation, so that functionality must be provided by the developer.

In the following example, a simplistic wizard setup is demonstrated. A button bar is added to the footer of the containing panel to provide navigation buttons. The buttons will be handled by a common navigation routine -- for this example, the implementation of that routine has been ommitted since it can be any type of custom logic. Note that other uses of a CardLayout (like a tab control) would require a completely different implementation. For serious implementations, a better approach would be to extend CardLayout to provide the custom functionality needed. Example usage:

    var navHandler = function(direction){
        // This routine could contain business logic required to manage the navigation steps.
        // It would call setActiveItem as needed, manage navigation button state, handle any
        // branching logic that might be required, handle alternate actions like cancellation
        // or finalization, etc.  A complete wizard implementation could get pretty
        // sophisticated depending on the complexity required, and should probably be
        // done as a subclass of CardLayout in a real-world implementation.
    };

    var card = new Ext.Panel({
        title: 'Example Wizard',
        layout:'card',
        activeItem: 0, // make sure the active item is set on the container config!
        bodyStyle: 'padding:15px',
        defaults: {
            // applied to each contained panel
            border:false
        },
        // just an example of one possible navigation scheme, using buttons
        bbar: [
            {
                id: 'move-prev',
                text: 'Back',
                handler: navHandler.createDelegate(this, [-1]),
                disabled: true
            },
            '->', // greedy spacer so that the buttons are aligned to each side
            {
                id: 'move-next',
                text: 'Next',
                handler: navHandler.createDelegate(this, [1])
            }
        ],
        // the panels (or "cards") within the layout
        items: [{
            id: 'card-0',
            html: '<h1>Welcome to the Wizard!</h1><p>Step 1 of 3</p>'
        },{
            id: 'card-1',
            html: '<p>Step 2 of 3</p>'
        },{
            id: 'card-2',
            html: '<h1>Congratulations!</h1><p>Step 3 of 3 - Complete</p>'
        }]
    });

## Config Options

Config Options | Defined By
--- | ---
| deferredRender : Boolean True to render each contained item at the time it becomes active, false to render all contained items as soon as the ... True to render each contained item at the time it becomes active, false to render all contained items as soon as the layout is rendered (defaults to false). If there is a significant amount of content or a lot of heavy controls being rendered into panels that are not displayed by default, setting this to true might improve performance. | CardLayout
| extraCls : String An optional extra CSS class that will be added to the container. This can be useful for adding customized styles to t... An optional extra CSS class that will be added to the container. This can be useful for adding customized styles to the container or any of its children using standard CSS rules. See Ext.Component.ctCls also. Note: `extraCls` defaults to `''` except for the following classes which assign a value by default: Absolute Layout : `'x-abs-layout-item'` Box Layout : `'x-box-item'` Column Layout : `'x-column'` To configure the above Classes with an extra CSS class append to the default. For example, for ColumnLayout:
    extraCls: 'x-column custom-class'
| ContainerLayout
| layoutOnCardChange : Boolean True to force a layout of the active item when the active card is changed. Defaults to false. | CardLayout

## Public Properties

Property | Defined By
--- | ---
| activeItem : Ext.Component A reference to the Ext.Component that is active. For example, if(myPanel.layout.activeItem.id == 'item-1') { ... } a... A reference to the Ext.Component that is active. For example,
    if(myPanel.layout.activeItem.id == 'item-1') { ... }
`activeItem` only applies to layout styles that can display items one at a time (like Ext.layout.AccordionLayout, Ext.layout.CardLayout and Ext.layout.FitLayout). Read-only. Related to Ext.Container.activeItem. | ContainerLayout
| fieldTpl : Ext.Template The Ext.Template used by Field rendering layout classes (such as Ext.layout.FormLayout) to create the DOM structure o... The Ext.Template used by Field rendering layout classes (such as Ext.layout.FormLayout) to create the DOM structure of a fully wrapped, labeled and styled form Field. A default Template is supplied, but this may be overriden to create custom field structures. The template processes values returned from Ext.layout.FormLayout.getTemplateArgs. | ContainerLayout
| if : Object This monitorResize flag will be renamed soon as to avoid confusion with the Container version which hooks onWindowRes... This monitorResize flag will be renamed soon as to avoid confusion with the Container version which hooks onWindowResize to doLayout monitorResize flag in this context attaches the resize event between a container and it's layout | ContainerLayout

## Public Methods

Method | Defined By
--- | ---
| parseMargins( Number|String v ) : Object Parses a number or string representing margin sizes into an object. Supports CSS-style margin declarations (e.g. 10, ... Parses a number or string representing margin sizes into an object. Supports CSS-style margin declarations (e.g. 10, "10", "10 10", "10 10 10" and "10 10 10 10" are all valid options and would return the same result) Parameters: `v` : Number|String The encoded margins Returns: `Object` An object with margin sizes for top, right, bottom and left | ContainerLayout
| setActiveItem( String/Number item ) : void Sets the active (visible) item in the layout. Sets the active (visible) item in the layout. Parameters: `item` : String/Number The string component id or numeric index of the item to activate Returns: void | CardLayout

## Public Events

This class has no public events.