jquery.choiceflow

Choiceflow is a jQuery plugin that provides you with an easy way to display and hide parts of your website. It can be used for step-by-step forms with a linear or decision based path. The most basic configuration relies on html attributes and does not require you to write JavaScript.

Overview

1. Install
2. Usage
3. A basic flow
4. Multiple flows
5. Active blocks and links
6. Customize showing and hiding of blocks
7. Events
8. choiceflow:display
9. choiceflow:canHide
10. choiceflow:canShow
11. choiceflow:show and choiceflow:hide
12. choiceflow:afterShow and choiceflow:afterHide
13. choiceflow:afterDisplay
14. Options
15. beforeLinkAction and afterLinkAction
16. Examples
17. Basic linear flow

1. Install

bower install westwerk-ac/jquery.choiceflow

2. Usage

i. A basic flow

To build a flow you need only two things: links and blocks.

• A link is a html element the user can click to display an block.
• A block is a html element that can be shown by clicking links.

A link can look like this:

<span data-choiceflow-value="block2">Next</span>

Or like this if you use bootstrap:

<button type="button" class="btn btn-primary" data-choiceflow-value="block2">Next</button>

The corresponding block could be this:

<div id="choiceflow-block-default-block2"></div>

When clicking a link with data-choiceflow-value="foo" the element with id="choiceflow-block-default-foo" is shown. All other blocks are hidden.

You cannot have blocks with identical ids. But you can display several blocks using one link with data-choiceflow-value="foo,bar".

ii. Multiple flows

You can group flows using the data-choiceflow-group attribute:

<span data-choiceflow-group="foo1" data-choiceflow-value="bar2">Next</span>
<div id="choiceflow-block-foo1-bar2"></div>

Defining no group is the same as having data-choiceflow-group="default".

When clicking a link, only other blocks of the same group are hidden.

iii. Active blocks and links

An element can only be a block if there is a corresponding link. All blocks are hidden per default. To have a block shown per default, add data-choiceflow-active="1" to at least one link that references the block.

<span data-choiceflow-value="block1" data-choiceflow-active="1">Next</span>

Sometimes you have a block that should be visible at first, but you don't want to link back to it. You can achieve this by having a hidden link inside the block:

<div id="choiceflow-block-default-block1">
	<span data-choiceflow-value="block1" data-choiceflow-active="1" style="display: none;"></span>
</div>

Alternatively if you want to use JS:

jQuery(function($) {
	$('#choiceflow-block-default-block1').choiceflow('display');
});

Active blocks have the choiceflow-block-active class set. Active links the choiceflow-active class.

You can check whether a block is active or not:

if ($('choiceflow-block-foo-bar').choiceflow('is-active')) {
	// stuff
}

iv. Customize showing and hiding of blocks

Per default choiceflow uses jQuery's show() and hide(). You can overwrite those with the `choiceflow:show|hide' events.

If you want to add checks to determine if a block should be displayed use the choiceflow:display|canShow|canHide events instead.

3. Events

When clicking a link or using js to display a block the following event are fired in that order:

Event	Fired	Can be used to ...
choiceflow:display	before displaying	... validate and prevent the action.
choiceflow:canHide	before displaying	... validate and prevent the action.
choiceflow:canShow	before displaying	... validate and prevent the action.
choiceflow:hide	before hiding a block	... overwrite how the block is hidden.
choiceflow:afterHide	after hiding a block	... save changes and change styles.
choiceflow:show	before showing a block	... overwrite how the block is shown.
choiceflow:afterShow	after showing a block	... change styles.
choiceflow:afterDisplay	after displaying	... set focus, etc.

i. choiceflow:display

This event is fired before anything else on each block that is going to be displayed, even if the block is already visible.

This event is called with 4 arguments: (event, blocks, group, aborted).

Argument	Type	Description
event	object	The default event object.
blocks	array	The blocks that will be displayed.
group	string	The group of the blocks.
aborted	bool	Whether another event aborted this action.

If you return false, the action is aborted for all blocks. The events choiceflow:display, choiceflow:canHide and choiceflow:canShow are still fired, but their results cannot change that the action is aborted.

Be careful with overlapping events. The return value of the last event counts.

ii. choiceflow:canHide

This event is identical with choiceflow:display, except that it is called on visible blocks that are going to be hidden.

This event suites great for form validation.

Example

In the following scenario the block choiceflow-block-foo-bar can only be hidden if the user filled all inputs. All attempts to move to another block will fail if this returns false;

$('#choiceflow-block-foo-bar').on('choiceflow:canHide', function() {
	var ok = true;
	$(this).find('input').each(function() {
		if ($(this).val() == "")
			ok = false;
	});
	return ok;
});

iii. choiceflow:canShow

This event is identical with choiceflow:display, except that it is called on hidden blocks that are going to be shown.

Example

In the following scenario the block choiceflow-block-foo-bar can only be shown if the user entered something in the input field with the id inputName.

$('#choiceflow-block-foo-bar').on('choiceflow:canShow', function() {
	return $('#inputName').val() != "";
});

iv. choiceflow:show and choiceflow:hide

These events are fired on each block that is definitely going to be shown or hidden.

This event is called with 3 arguments: (event, block, group).

Argument	Type	Description
event	object	The default event object.
block	string	The block that will be shown/hidden.
group	string	The group of the block.

You can use these events to overwrite the default show/hide action if you return false.

You should not try to prevent displaying here. Use the choiceflow:display|canShow|canHide events for that.

Example

This will make the blocks smoothly slide up and down.

$('[id^="choiceflow-block-"]')
	// overwrite show event
	.on('choiceflow:show', function() {
		// show it smooth
		$(this).slideDown();
		// don't do the normal show stuff
		return false;
	})
	// overwrite hide event
	.on('choiceflow:hide', function() {
		// hide it smooth
		$(this).slideUp();
		// don't do the normal hide stuff
		return false;
	});

v. choiceflow:afterShow and choiceflow:afterHide

These events are fired on each block immediately after it was shown or hidden. If multiple blocks are shown/hidden the choiceflow:afterShow|afterHide event is called before the next block's choiceflow:show|hide event.

This event is called with 3 arguments: (event, block, group).

Argument	Type	Description
event	object	The default event object.
block	string	The block that was shown/hidden.
group	string	The group of the block.

You can use these events to apply css, set the focus, scoll to the block, etc.

Example

This will focus on the first input element of the shown block.

$('[id^="choiceflow-block-"]').on('choiceflow:afterShow', function() {
	$(this).find('input').filter(':first').focus();
});

vi. choiceflow:afterDisplay

This event is fired after each show and hide action is performed. It is fired on each block that was displayed, even if it was visible before.

This event is called with 4 arguments: (event, blocks, hiddenBlocks, group).

Argument	Type	Description
event	object	The default event object.
blocks	array	The blocks that were displayed.
hiddenBlocks	array	The blocks that were hidden.
group	string	The group of the block.

If a link action is not performed, due to the choiceflow:display|canShow|canHide events, this event is not fired.

If a link does has no effect, because the blocks to show and hide were already shown or hidden, this event still fires.

4. Options

Define options like this:

$.choiceflow({
	'foo': 'bar'
});

Available options:

Option	Type	Description
beforeLinkAction	function	Called when a link is clicked.
afterLinkAction	function	Called after a link action was performed.

i. beforeLinkAction and afterLinkAction

This options take a function with the following arguments:

Argument	Type	Description
blocks	array	The blocks that the link reveals.
show	array	The blocks that are going to be shown and were hidden before.
hide	array	The blocks that are going to be hidden and were shown before.
group	string	The group of the link.

You can return false from the beforeLinkAction function to prevent the link action.

5. Examples

i. Basic linear flow

Step by step through 3 blocks.

<div id="choiceflow-block-default-1">
	<!-- make block 1 active -->
	<span style="display: none;" data-choiceflow-value="1" data-choiceflow-active="1"></span>
	BLOCK 1
	<!-- link to block 2 -->
	<span data-choiceflow-value="2">Next</span>
</div>
<div id="choiceflow-block-default-2">
	BLOCK 2
	<!-- link to block 3 -->
	<span data-choiceflow-value="3">Next</span>
</div>
<div id="choiceflow-block-default-3">
	BLOCK 3
</div>