Form Controller
Adds form management features to any backend page.
- Configuring the Form Behavior
- Create Page
- Update Page
- Preview Page
- Custom Messages
- Restricting with Permissions
- Defining Form Fields
- Field Properties
- Tab Properties
- Custom Field Types
- Nested Field Selection
- Field Facades
- Form Views
- Create View
- Update View
- Preview View
- Extending Form Behavior
- Extending the Form Configuration
- Overriding Controller Action
- Overriding Controller Redirect
- Extending Form Model Query
- Extending Form Fields
- Filtering Form Fields
- Validating Form Fields
The Backend\Behaviors\FormController
class is a controller behavior used for easily adding form functionality to a backend page. The behavior provides three pages called Create, Update and Preview. The Preview page is a read-only version of the Update page. When you use the form behavior you don't need to define the create
, update
and preview
actions in the controller - the behavior does it for you. However you should provide the corresponding view files.
Form behavior depends on form field definitions and a model class. In order to use the form behavior you should add it to the $implement
property of the controller class. Also, the $formConfig
class property should be defined and its value should refer to the YAML file used for configuring the behavior properties.
namespace Acme\Blog\Controllers;
class Categories extends \Backend\Classes\Controller
{
public $implement = [
\Backend\Behaviors\FormController::class
];
public $formConfig = 'config_form.yaml';
}
Very often the form and list controller are used together in a same controller.
# Configuring the Form Behavior
The configuration file referred in the $formConfig
property is defined in YAML format. The file should be placed into the controller's view directory. Below is an example of a typical form behavior configuration file.
# ===================================
# Form Behavior Config
# ===================================
name: Blog Category
form: $/acme/blog/models/post/fields.yaml
modelClass: Acme\Blog\Post
create:
title: New Blog Post
update:
title: Edit Blog Post
preview:
title: View Blog Post
The following properties are required in the form configuration file.
Property | Description |
---|---|
name | the name of the object being managed by this form. |
form | a configuration array or reference to a form field definition file, see form fields. |
modelClass | a model class name, the form data is loaded and saved against this model. |
The configuration properties listed below are optional. Define them if you want the form behavior to support the Create, Update or Preview pages.
Property | Description |
---|---|
defaultRedirect | used as a fallback redirection page when no specific redirect page is defined. |
create | a configuration array or reference to a config file for the Create page. |
update | a configuration array or reference to a config file for the Update page. |
preview | a configuration array or reference to a config file for the Preview page. |
customMessages | customize the messages used in the Form Controllers. |
permissions | apply restrictions to certain actions provided by the Form Controller. |
# Create Page
To support the Create page add the following configuration to the YAML file.
create:
title: New Blog Post
redirect: acme/blog/posts/update/:id
redirectClose: acme/blog/posts
The following properties are supported for the Create page.
Property | Description |
---|---|
title | a page title, can refer to a localization string. |
redirect | redirection page when record is saved. |
redirectClose | redirection page when record is saved and the close post variable is sent with the request. |
form | overrides the default form fields definitions for the create page only. |
# Update Page
To support the Update page add the following configuration to the YAML file.
update:
title: Edit Blog Post
redirect: acme/blog/posts
The following properties are supported for the Update page.
Property | Description |
---|---|
title | a page title, can refer to a localization string. |
redirect | redirection page when record is saved. |
redirectClose | redirection page when record is saved and close post variable is sent with the request. |
form | overrides the default form fields definitions for the update page only. |
# Preview Page
To support the Preview page add the following configuration to the YAML file:
preview:
title: View Blog Post
The following properties are supported for the Preview page.
Property | Description |
---|---|
title | a page title, can refer to a localization string. |
form | overrides the default form fields definitions for the preview page only. |
# Custom Messages
Specify the customMessages
property to override the default messages used by the Form Controller. The values can be plain text or can refer to a localization string.
customMessages:
notFound: Did not find the thing
flashCreate: New thing created
flashUpdate: Updated that thing
flashDelete: Thing is gone
You may also modify messages in the context of the form being displayed. The following will override the notFound
message for the update
context only.
update:
customMessages:
notFound: Nothing found when updating
The following messages are available to override as custom messages.
View the list of available messages
Message | Default Message |
---|---|
notFound | Form record with an ID of :id could not be found. |
flashCreate | :name Created |
flashUpdate | :name Updated |
flashDelete | :name Deleted |
# Restricting with Permissions
Specify the permissions
property to apply restrictions to actions provided by the Form Controller. Use permission values that the current backend user must have in order for the field to be used. Supports either a string for a single permission or an array of permissions of which only one is needed to grant access.
permissions:
modelCreate: admins.manage.create
modelDelete: admins.manage.delete
The following properties are available to override as required permissions.
View the list of available messages
Message | Default Message |
---|---|
modelCreate | required to create new records. |
modelUpdate | required to modify existing records. |
modelPreview | required to preview existing records. |
modelDelete | required to delete existing records. |
# Defining Form Fields
Form fields are defined with the YAML file. The form fields configuration is used by the form behavior for creating the form controls and binding them to the model fields. The file is placed to a subdirectory of the models directory of a plugin. The subdirectory name matches the model class name written in lowercase. The file name doesn't matter, but fields.yaml and form_fields.yaml are common names. Example form fields file location:
├── plugins
| └── acme
| └── blog
| └── models
| ├── post ← Config Directory
| | └── fields.yaml ← Config File
| └── Post.php ← Model Class
Fields can be placed in three areas, the outside area, primary tabs or secondary tabs. The next example shows the typical contents of a form fields definition file.
# ===================================
# Form Field Definitions
# ===================================
fields:
blog_title:
label: Blog Title
description: The title for this blog
published_at:
label: Published date
description: When this blog post was published
type: datepicker
# [...]
tabs:
fields:
# [...]
secondaryTabs:
fields:
# [...]
# Field Properties
For each field you can specify these common properties, where applicable.
Property | Description |
---|---|
label | a name when displaying the form field to the user. |
type | defines how this field should be rendered, see form field definitions. Default: text . |
span | aligns the form field to one side. Options: auto , left , right , row , full . Default: full . |
spanClass | used with the span row property to display the form as a Bootstrap grid, for example, spanClass: col-xs-4 . |
size | specifies a field size for fields that use it, for example, the textarea field. Options: tiny , small , large , huge , giant . |
placeholder | if the field supports a placeholder value. |
comment | places a descriptive comment below the field. |
commentAbove | places a comment above the field. |
commentHtml | allow HTML markup inside the comment. Options: true , false . |
default | specify the default value for the field. For dropdown , checkboxlist , radio and balloon-selector widgets, you may specify an option key here to have it selected by default. |
defaultFrom | takes the default value from the value of another field. |
tab | assigns the field to a tab. |
cssClass | assigns a CSS class to the field container. |
readOnly | prevents the field from being modified. Options: true , false . |
disabled | prevents the field from being modified and excludes it from the saved data. Options: true , false . |
hidden | hides the field from the view and excludes it from the saved data. Options: true , false . |
stretch | specifies if this field stretches to fit the parent height. |
context | specifies what context should be used when displaying the field. Context can also be passed by using an @ symbol in the field name, for example, name@update . |
dependsOn | an array of other field names this field depends on, when the other fields are modified, this field will update. |
changeHandler | the name of an AJAX handler to call when the field value is changed, optional. |
trigger | specify conditions for this field using trigger events. |
preset | allows the field value to be initially set by the value of another field, converted using the input preset converter. |
required | places a red asterisk next to the field label to indicate it is required. Be sure to use the validation trait on the model as this is not enforced by the form controller. |
attributes | specify custom HTML attributes to add to the form field element. |
containerAttributes | specify custom HTML attributes to add to the form field container. |
permissions | the permissions that the current backend user must have in order for the field to be used. Supports either a string for a single permission or an array of permissions of which only one is needed to grant access. |
# Tab Properties
An example of specifying field definitions in tabs.
tabs:
fields:
username:
type: text
label: Username
tab: User
groups:
type: relation
label: Groups
tab: Groups
For each tab definition, namely tabs
and secondaryTabs
, you can specify these properties.
Property | Description |
---|---|
stretch | specifies if this tab stretches to fit the parent height. |
defaultTab | the default tab to assign fields to. Default: Misc. |
activeTab | selected tab when the form first loads, name or index. Default: 1 |
icons | assign icons to tabs using tab names as the key. |
lazy | array of tabs to be loaded dynamically when clicked. Useful for tabs that contain large amounts of content. |
linkable | determines if the tabs can be linked using URL fragments. Default: true |
cssClass | assigns a CSS class to the tab container. |
paneCssClass | assigns a CSS class to an individual tab pane. Value is an array, key is tab index or label, value is the CSS class. It can also be specified as a string, in which case the value will be applied to all tabs. |
An example applying properties to tabs.
tabs:
stretch: true
defaultTab: User
cssClass: text-blue
lazy:
- Groups
paneCssClass:
1: first-tab
2: second-tab
icons:
User: icon-user
Groups: icon-group
fields:
# [...]
# Custom Field Types
There are various native field types that can be used for the type setting. To learn more, take a look at the available form field definitions. It is possible to render a field directly by specifying the PHP class name of a form field widget.
blog_content:
type: Backend\FormWidgets\RichEditor
size: huge
# Nested Field Selection
avatar[name]:
label: Avatar
comment: will be saved in the Avatar table
The above example would fetch and save the value in PHP equivalent of $record->avatar->name
or $record->avatar['name']
respectively.
# Field Facades
Sometimes you may need to display a field while preventing it from being submitted. A field can be defined as a facade by adding an underscore (_) before the name of the field. These fields are purged automatically and no longer saved to the model, such as with the following _map
field.
address:
label: Title
type: text
_map:
label: Point your address on the map
type: mapviewer
# Form Views
For each page your form supports Create, Update and Preview you should provide a view file with the corresponding name - create.htm, update.htm and preview.htm.
The form behavior adds two methods to the controller class: formRender
and formRenderPreview
. These methods render the form controls configured with the YAML file described above.
# Create View
The create.htm view represents the Create page that allows users to create new records. A typical Create page contains breadcrumbs, the form itself, and the form buttons. The data-request attribute should refer to the onSave
AJAX handler provided by the form behavior. Below is a contents of the typical create.htm form.
<?= Form::open(['class'=>'layout']) ?>
<div class="layout-row">
<?= $this->formRender() ?>
</div>
<div class="form-buttons">
<div class="loading-indicator-container">
<button
type="button"
data-request="onSave"
data-request-data="close:true"
data-hotkey="ctrl+enter, cmd+enter"
data-load-indicator="Creating Category..."
class="btn btn-default">
Create and Close
</button>
<span class="btn-text">
or <a href="<?= Backend::url('acme/blog/categories') ?>">Cancel</a>
</span>
</div>
</div>
<?= Form::close() ?>
# Update View
The update.htm view represents the Update page that allows users to update or delete existing records. A typical Update page contains breadcrumbs, the form itself, and the form buttons. The Update page is very similar to the Create page, but usually has the Delete button. The data-request attribute should refer to the onSave
AJAX handler provided by the form behavior. Below is a contents of the typical update.htm form.
<?= Form::open(['class'=>'layout']) ?>
<div class="layout-row">
<?= $this->formRender() ?>
</div>
<div class="form-buttons">
<div class="loading-indicator-container">
<button
type="button"
data-request="onSave"
data-request-data="close:true"
data-hotkey="ctrl+enter, cmd+enter"
data-load-indicator="Saving Category..."
class="btn btn-default">
Save and Close
</button>
<button
type="button"
class="oc-icon-trash-o btn-icon danger pull-right"
data-request="onDelete"
data-load-indicator="Deleting Category..."
data-request-confirm="Do you really want to delete this category?">
</button>
<span class="btn-text">
or <a href="<?= Backend::url('acme/blog/categories') ?>">Cancel</a>
</span>
</div>
</div>
<?= Form::close() ?>
# Preview View
The preview.htm view represents the Preview page that allows users to preview existing records in the read-only mode. A typical Preview page contains breadcrumbs and the form itself. Below is a contents of the typical preview.htm form.
<div class="form-preview">
<?= $this->formRenderPreview() ?>
</div>
# Extending Form Behavior
Sometimes you may wish to modify the default form behavior and there are several ways you can do this.
# Extending the Form Configuration
You may extend the form configuration dynamically using the formGetConfig
method.
public function formGetConfig()
{
$config = $this->asExtension('FormController')->formGetConfig();
// Set the active tab dynamically
$config->form['tabs']['activeTab'] = 'Content';
return $config;
}
# Overriding Controller Action
You can use your own logic for the create
, update
or preview
action method in the controller, then optionally call the Form behavior parent method.
public function update($recordId, $context = null)
{
//
// Do any custom code here
//
// Call the FormController behavior update() method
return $this->asExtension('FormController')->update($recordId, $context);
}
# Overriding Controller Redirect
You can specify the URL to redirect to after the model is saved by overriding the formGetRedirectUrl
method. This method returns the location to redirect to with relative URLs being treated as backend URLs.
public function formGetRedirectUrl($context = null, $model = null)
{
return 'https://octobercms.com';
}
# Extending Form Model Query
The lookup query for the form database model can be extended by overriding the formExtendQuery
method inside the controller class. This example will ensure that soft deleted records can still be found and updated, by applying the withTrashed scope to the query:
public function formExtendQuery($query)
{
$query->withTrashed();
}
# Extending Form Fields
You can extend the fields of another controller from outside by calling the extendFormFields
static method on the controller class. This method can take three arguments, $form will represent the Form widget object, $model represents the model used by the form and $context is a string containing the form context. Take this controller for example:
class Categories extends \Backend\Classes\Controller
{
public $implement = [
\Backend\Behaviors\FormController::class
];
public $formConfig = 'config_form.yaml';
}
Using the extendFormFields
method you can add extra fields to any form rendered by this controller. Since this has the potential to affect all forms used by this controller, it is a good idea to check the $model is of the correct type. Here is an example:
Categories::extendFormFields(function($form, $model, $context) {
if (!$model instanceof MyModel) {
return;
}
$form->addFields([
'my_field' => [
'label' => 'My Field',
'comment' => 'This is a custom field I have added.',
],
]);
});
You can also extend the form fields internally by overriding the formExtendFields
method inside the controller class. This will only affect the form used by the FormController
behavior.
class Categories extends \Backend\Classes\Controller
{
// ...
public function formExtendFields($form)
{
$form->addFields([...]);
}
}
The following methods are available on the $form object.
Method | Description |
---|---|
addFields | adds new fields to the outside area |
addTabFields | adds new fields to the tabbed area |
addSecondaryTabFields | adds new fields to the secondary tabbed area |
removeField | remove a field from any areas |
Each method takes an array of fields similar to the form field configuration.
# Filtering Form Fields
As described in the field dependencies section, you may also implement form field filtering by extension by hooking in to the form.filterFields
event.
User::extend(function ($model) {
$model->bindEvent('model.form.filterFields', function ($formWidget, $fields, $context) use ($model) {
if ($model->source_type === 'http') {
$fields->source_url->hidden = false;
$fields->git_branch->hidden = true;
}
elseif ($model->source_type === 'git') {
$fields->source_url->hidden = false;
$fields->git_branch->hidden = false;
}
else {
$fields->source_url->hidden = true;
$fields->git_branch->hidden = true;
}
});
});
# Validating Form Fields
To validate the fields of your form you can make use of the Validation trait in your model.