ember-form-master-2000

A flexible and lightweight ember-cli addon that tries to make forms easier to deal with.

---

NOTE

This project is in the process of moving towards Ember 2.1. There is still some work to be done, so please have patience.

Installation

This is an ember-cli addon and can be installed using npm:

npm install --save-dev ember-form-master-2000

Demo

You can see the basic dummy app here:

• Dummy App
• Tests

Overview

Ember Form Master 2000 is an extensible library for creating forms in Ember. The library comes out of the box with the standard form components you would expect and it is easy to add more custom components as needed.

FM2000's primary entry point is the fm-field component. This is used to render a form field to the page. Even when you are making custom components you will still use fm-field to render them.

Every time a field is rendered, it renders a display and a widget. displays are responible for the layout and css formatting of your form field. For example, using different displays you could opt to render a field using horizontal form style or a stacked form style. widgets are responsible for encapulsating the actual component that is manipulated. There are built in widgets for things like input and textarea but you could add a custom date picker widget or a fancy autocomplete widget. To learn more about creating custom displays and widgets see the Extending Form Master below.

Validation

Currently FM2000 is all about rendering interactive forms in a standardized way with a concise and extensible syntax. FM2000 is not about doing form validation or managing CRUD logic. We may consider adding this functionality in the future but it will be as a separate layer from the existing components which are purely responsible for form display.

Built-In Components

The following is the basic API for Ember 2.3+. The hash helper that is used below is not present in Ember 2.0-2.2. We are currently still supporting setting the widgetAttrs values for the default widgets directly on the fm-field component. For those versions just specifiy widgetAttrs directly on the the component. The supported attributes for this are listed in the WIDGET_ATTR_ALIASES constant in addon/components/fm-field.js.

{{#fm-form action='submit'}}

  {{fm-field label='First Name'
    value=model.exampleModel.first_name
    errors=model.exampleModel.errors.first_name
    placeholder='Foo'
  }}

  {{fm-field label='Last Name'
    value=model.exampleModel.last_name
    errors=model.exampleModel.errors.last_name
    placeholder='Bar'
  }}

  {{fm-field
    label='Write an Essay'
    type='textarea'
    value=model.exampleModel.essay
    errors=model.exampleModel.errors.essay
    rows='6'
    helptext='Make sure its good!'
    data-test='master-2000'
  }}

  {{fm-field
    label='Choose Something'
    type='select'
    content=model.selectOptions
    optionValuePath='value'
    optionLabelPath='label'
    prompt='Select Something'
    value=model.exampleModel.language
    action=(action (mut model.exampleModel.language))
    errors=model.exampleModel.errors.language
  }}

  {{fm-field
    widget='checkbox'
    label='Are you awesome?'
    value=model.exampleModel.isAwesome
    errors=model.exampleModel.errors.isAwesome
  }}

  {{fm-field
    widget='radio-group'
    label='Choose the best language'
    name='bestLanguage'
    content=model.radioOptions
    optionValuePath='value'
    optionLabelPath='label'
    value=model.exampleModel.bestLanguage
    errors=model.exampleModel.errors.bestLanguage
  }}

  {{fm-submit value='Submit the Form' disabled=model.disableSubmit}}

{{/fm-form}}

Extending Form Master

There are two ways to extend form-master's built in functionality.

Widgets

Widgets are responsible for creating a UI object to manipulate some data. Form-master provides some builtin widgets such as select, textarea and radio-group. Note that some widgets are interchangeable for the same type of data. Both a textarea and input work well for manipulating a string attribute. Similarly, a selection from a predefined list could be done with either a select or a radio-group widget.

You can easily override any of the existing widgets to augment or modify their functionality.

Widgets should do as little as possible to affect their appearance. They should not specify css classes and should contain as little dom in their templates as is necessary for them to function. For an example of this, look at how fm-widgets/checkbox contains only the checkbox element itself and the label and surrounding divs are in the fm-displays/checkbox component.

You can also create your own custom widgets. For instance, you may want to create an autocompleting text input. This would be easily done by creating a new component called fm-widgets/autocomplete. You would then be able to create a field with an autocomplete widget as follows:

{{fm-field
  widget='autocomplete'
  value=value
  widgetAttrs=(hash
    choices=autocompleteChoices
    placeholder=placeholder
  )
}}

The fm-field component will take care of adding labels, errors and formatting classes around your autocomplete widget. Meanwhile your autocomplete widget can focus solely on adding the extra autocomplete functionality you want.

You can create custom form widgets easily. Simply create a new component named as fm-widgets/<your widget name>. A widget will receive the following attrs:

• value: the current value of the input.

• action (optional): action to call with a new value chosen through user interaction with the widget. If you do not want to support actions-up/data-down design you can modify value directly and ignore action.

• widgetAttrs: an Ember.Object which is used as a vessel to pass any custom values for your widget. For instance a select, widget would look for the choices, labelField and valueField properties in the widgetAttrs property.

• onUserInteraction: your custom widget needs to call this action whenever it is manipulated. This lets fm-field know when it should show errors on the form field.

• classNames: allows the fm-field's display component to add certain standard css classes.

Displays

Displays let you customize the aesthetics of a form field. For instance, you may want to create a display where the fields label and inputs appear in rows. You could do this by creating a component called fm-displays/horizontal. Your templates/components/fm-displays/horizontal.hbs might look like this:

<div class="{{styles.wrapperClass}}">
  <label for="{{forAttribute}}" class="col-sm-2 {{styles.labelClass}}">
    {{label}}
  </label>
  <div class="col-sm-10">
    {{yield inputClasses}}
  </div>

  {{#if visibleErrors.length}}
    <span class="{{styles.errortextClass}}">
      {{visibleErrors.firstObject}}
    </span>
  {{/if}}

  {{#if helptext}}
    <span class="{{styles.helptextClass}}">
      {{helptext}}
    </span>
  {{/if}}
</div>

This widget will be included wherever you place the yield statement. The inputClasses attribute is passed to the yield statement to specify classes that should be applied to the widget itself.

You can now use this display anywhere in your application by simply specifying the layout when creating an fm-field:

{{fm-field
  display='horizontal'
  widget='input'
  value=myValue
  errors=errors
  placholder=placehodler
}}

Note how we defer to styles property for class names where possible. This ties in the fm-config service which provides easy configuration of form classes on a global basis.

The best place to start for creating a display is to look at fm-displays/default.hbs.

Errors

Displaying validation errors is a core requirement for any form library. To keep things simple, you must explicitly tell fm-fields what errors should be displayed. When provided an array of errors, fm-field will display the first error.

var model = Ember.Object.create();
model.set('errors', Ember.Object.create({first_name: ['Required', 'Too short']}));

{{fm-field type='text' value=model.first_name errors=model.errors.first_name}}

By default, fm-field displays any error that is included in the errors property. If you do not want errors to be displayed until a fm-field has been manipulated for the first time, set the showErrorsByDefault property in the fm-config service to false. With this change, fm-field will only display errors when it has been notified by its widget that the widget has received user interaction. If you are using the fm-form wrapper component and fm-submit then clicking the fm-submit button will also cause errors to display.

Minor Customizations

If you need to make minor adjustments to classnames of the elements, you can easily override the default initializer with your own. The default initializer can be found here, which imports the default configuration from the addon directory.

Demo App

You can see a more holistic example by looking at the Dummy app that we use to test against. The index.hbs template and the application route are of particular interest.