# Class: GridSection

## LuCI.form. GridSection

The `GridSection` class maps all or - if `filter()` is overwritten - a subset of the underlying UCI configuration sections of a given type.

A grid section functions similar to a `LuCI.form.TableSection` but supports tabbing in the modal overlay. Option elements added with `option()` are shown in the table while elements added with `taboption()` are displayed in the modal popup.

Another important difference is that the table cells show a readonly text preview of the corresponding option elements by default, unless the child option element is explicitely made writable by setting the `editable` property to `true`.

Additionally, the grid section honours a `modalonly` property of child option elements. Refer to the `AbstractValue` documentation for details.

Layout wise, a grid section looks mostly identical to table sections.

#### new LuCI.form.GridSection(form, section_type, title, description)

form.js, line 2873

  Name | Type | Description
  --- | --- | ---
  `form` | LuCI.form.Map | LuCI.form.JSONMap | The configuration form this section is added to. It is automatically passed by `section()`.
  `section_type` | string | The type of the UCI section to map.
  `title` | string | optional The title caption of the form section element.
  `description` | string | optional The description text of the form section element.

### Extends

- LuCI.form.TableSection

### Members

#### addbtntitlestring function

  Override the caption used for the section add button at the bottom of the section form element. If set to a string, it will be used as-is, if set to a function, the function will be invoked and its return value is used as caption, after converting it to a string. If this property is not set, the default is `Add`.

  Default Value:
    - null

#### addremoveboolean

  If set to `true`, the user may add or remove instances from the form section widget, otherwise only preexisting sections may be edited. The default is `false`.

  Default Value:
    - false

#### anonymousboolean

  If set to `true`, mapped section instances are treated as anonymous UCI sections, which means that section instance elements will be rendered without title element and that no name is required when adding new sections. The default is `false`.

  Default Value:
    - false

#### exteditstring function

  Enables a per-section instance row `Edit` button which triggers a certain action when clicked. If set to a string, the string value is used as `String.format()` pattern with the name of the underlying UCI section as first format argument. The result is then interpreted as URL which LuCI will navigate to when the user clicks the edit button.

  If set to a function, this function will be registered as click event handler on the rendered edit button, receiving the section instance name as first and the DOM click event as second argument.

  Default Value:
    - null

#### max_colsnumber

  Specify a maximum amount of columns to display. By default, one table column is rendered for each child option of the form section element. When this option is set to a positive number, then no more columns than the given amount are rendered. When the number of child options exceeds the specified amount, a `More…` button is rendered in the last column, opening a modal dialog presenting all options elements in `NamedSection` style when clicked.

  Default Value:
    - null

#### modaltitlestring function

  Override the per-section instance modal popup title caption shown when clicking the `More…` button in a section specifying `max_cols`. If set to a string, it will be used as `String.format()` pattern with the name of the underlying UCI section as first argument, if set to a function, the function will be invoked with the section name as first argument and its return value is used as caption, after converting it to a string. If this property is not set, the default is the name of the underlying UCI configuration section.

  Default Value:
    - null

#### nodescriptionsboolean

  If set to `true`, the header row with the options descriptions will not be displayed. By default, descriptions row is automatically displayed when at least one option has a description.

  Default Value:
    - false

#### readonlyparentoptionLuCI.form.AbstractValue

  Access the parent option container instance.

  In case this section is nested within an option element container, this property will hold a reference to the parent option instance.

  If this section is not nested, the property is `null`.

#### rowcolorsboolean

  If set to `true`, alternating `cbi-rowstyle-1` and `cbi-rowstyle-2` CSS classes are added to the table row elements. Not all LuCI themes implement these row style classes. The default is `false`.

  Default Value:
    - false

#### sectiontitlestring function

  Override the per-section instance title caption shown in the first column of the table unless `anonymous` is set to true. If set to a string, it will be used as `String.format()` pattern with the name of the underlying UCI section as first argument, if set to a function, the function will be invoked with the section name as first argument and its return value is used as caption, after converting it to a string. If this property is not set, the default is the name of the underlying UCI configuration section.

  Default Value:
    - null

#### sortableboolean

  If set to `true`, a sort button is added to the last column, allowing the user to reorder the section instances mapped by the section form element.

  Default Value:
    - false

#### tabbedboolean

  When set to `true`, instead of rendering section instances one below another, treat each instance as separate tab pane and render a tab menu at the top of the form section element, allowing the user to switch among instances. The default is `false`.

  Default Value:
    - false

#### uciconfigstring

  Override the UCI configuration name to read the section IDs from. By default, the configuration name is inherited from the parent `Map`. By setting this property, a deviating configuration may be specified. The default is `null`, means inheriting from the parent form.

  Default Value:
    - null

### Methods

#### inherited abstractaddModalOptions(modalSection, section_id, ev){*|Promise.<*>}

form.js, line 2803

  Add further options to the per-section instanced modal popup.

  This function may be overwritten by user code to perform additional setup steps before displaying the more options modal which is useful to e.g. query additional data or to inject further option elements.

  The default implementation of this function does nothing.

  Name | Type | Description
  --- | --- | ---
  `modalSection` | LuCI.form.NamedSection | The `NamedSection` instance about to be rendered in the modal popup.
  `section_id` | string | The ID of the underlying UCI section the modal popup belongs to.
  `ev` | Event | The DOM event emitted by clicking the `More…` button.

  ##### Returns:

  Type | Description
  --- | ---
  * | Promise.<*> | Return values of this function are ignored but if a promise is returned, it is run to completion before the rendering is continued, allowing custom logic to perform asynchroneous work before the modal dialog is shown.

#### inherited append(element)

form.js, line 210

  Add another form element as children to this element.

  Name | Type | Description
  --- | --- | ---
  `element` | AbstractElement | The form element to add.

#### inherited cfgvalue(section_id, option){null|string|Array.<string>|Object.<string, (null|string|Array.<string>)>}

form.js, line 1078

  Query underlying option configuration values.

  This function is sensitive to the amount of arguments passed to it; if only one argument is specified, the configuration values of all options within this section are returned as dictionary.

  If both the section ID and an option name are supplied, this function returns the configuration value of the specified option only.

  Name | Type | Description
  --- | --- | ---
  `section_id` | string | The configuration section ID
  `option` | string | optional The name of the option to query

  ##### Returns:

  Type | Description
  --- | ---
  null | string | Array.<string> | Object.<string, (null|string|Array.<string>)> | Returns either a dictionary of option names and their corresponding configuration values or just a single configuration value, depending on the amount of passed arguments.

#### inherited abstractfilter(section_id){boolean}

form.js, line 882

  Filter UCI section IDs to render.

  The filter function is invoked for each UCI section ID of a given type and controls whether the given UCI section is rendered or ignored by the form section element.

  The default implementation always returns `true`. User code or classes extending `AbstractSection` may overwrite this function with custom implementations.

  Name | Type | Description
  --- | --- | ---
  `section_id` | string | The UCI section ID to test.

  ##### Returns:

  Type | Description
  --- | ---
  boolean | Returns `true` when the given UCI section ID should be handled and `false` when it should be ignored.

#### inherited formvalue(section_id, option){null|string|Array.<string>|Object.<string, (null|string|Array.<string>)>}

form.js, line 1111

  Query underlying option widget input values.

  This function is sensitive to the amount of arguments passed to it; if only one argument is specified, the widget input values of all options within this section are returned as dictionary.

  If both the section ID and an option name are supplied, this function returns the widget input value of the specified option only.

  Name | Type | Description
  --- | --- | ---
  `section_id` | string | The configuration section ID
  `option` | string | optional The name of the option to query

  ##### Returns:

  Type | Description
  --- | ---
  null | string | Array.<string> | Object.<string, (null|string|Array.<string>)> | Returns either a dictionary of option names and their corresponding widget input values or just a single widget input value, depending on the amount of passed arguments.

#### inherited getOption(option){null|LuCI.form.AbstractValue|Object.<string, LuCI.form.AbstractValue>}

form.js, line 1177

  Obtain underlying option objects.

  This function is sensitive to the amount of arguments passed to it; if no option name is specified, all options within this section are returned as dictionary.

  If an option name is supplied, this function returns the matching LuCI.form.AbstractValue instance only.

  Name | Type | Description
  --- | --- | ---
  `option` | string | optional The name of the option object to obtain

  ##### Returns:

  Type | Description
  --- | ---
  null | LuCI.form.AbstractValue | Object.<string, LuCI.form.AbstractValue> | Returns either a dictionary of option names and their corresponding option instance objects or just a single object instance value, depending on the amount of passed arguments.

#### inherited getUIElement(section_id, option){null|LuCI.ui.AbstractElement|Object.<string, (null|LuCI.ui.AbstractElement)>}

form.js, line 1147

  Obtain underlying option LuCI.ui widget instances.

  This function is sensitive to the amount of arguments passed to it; if only one argument is specified, the LuCI.ui widget instances of all options within this section are returned as dictionary.

  If both the section ID and an option name are supplied, this function returns the LuCI.ui widget instance value of the specified option only.

  Name | Type | Description
  --- | --- | ---
  `section_id` | string | The configuration section ID
  `option` | string | optional The name of the option to query

  ##### Returns:

  Type | Description
  --- | ---
  null | LuCI.ui.AbstractElement | Object.<string, (null|LuCI.ui.AbstractElement)> | Returns either a dictionary of option names and their corresponding widget input values or just a single widget input value, depending on the amount of passed arguments.

#### inherited load(){Promise.<void>}

form.js, line 897

  Load the configuration covered by this section.

  The `load()` function recursively walks the section element tree and invokes the load function of each child option element.

  ##### Returns:

  Type | Description
  --- | ---
  Promise.<void> | Returns a promise resolving once the values of all child elements have been loaded. The promise may reject with an error if any of the child elements load functions rejected with an error.

#### inherited option(optionclass, classargs){LuCI.form.AbstractValue}

form.js, line 1010

  Add a configuration option widget to the section.

  Note that `taboption()` should be used instead if this form section element uses tabs.

  Name | Type | Description
  --- | --- | ---
  `optionclass` | LuCI.form.AbstractValue | The option class to use for rendering the configuration option. Note that this value must be the class itself, not a class instance obtained from calling `new`. It must also be a class dervied from `LuCI.form.AbstractSection`.
  `classargs` | * | repeatable Additional arguments which are passed as-is to the contructor of the given option class. Refer to the class specific constructor documentation for details.

  ##### Throws:

  Throws a `TypeError` exception in case the passed class value is not a descendent of `AbstractValue`.

  Type
    TypeError

  ##### Returns:

  Type | Description
  --- | ---
  LuCI.form.AbstractValue | Returns the instantiated option class instance.

#### inherited parse(){Promise.<void>}

form.js, line 3021

  Parse this sections form input.

  The `parse()` function recursively walks the section element tree and triggers input value reading and validation for each encountered child option element.

  Options which are hidden due to unsatisified dependencies are skipped.

  ##### Returns:

  Type | Description
  --- | ---
  Promise.<void> | Returns a promise resolving once the values of all child elements have been parsed. The returned promise is rejected if any parsed values are not meeting the validation constraints of their respective elements.

#### inherited stripTags(input){string}

form.js, line 286

  Strip any HTML tags from the given input string.

  Name | Type | Description
  --- | --- | ---
  `input` | string | The input string to clean.

  ##### Returns:

  Type | Description
  --- | ---
  string | The cleaned input string with HTML removes removed.

#### tab(name, title, description)

form.js, line 2942

  Add an option tab to the section.

  The modal option elements of a grid section may be divided into multiple tabs to provide a better overview to the user.

  Before options can be moved into a tab pane, the corresponding tab has to be defined first, which is done by calling this function.

  Note that tabs are only effective in modal popups, options added with `option()` will not be assigned to a specific tab and are rendered in the table view only.

  Name | Type | Description
  --- | --- | ---
  `name` | string | The name of the tab to register. It may be freely chosen and just serves as an identifier to differentiate tabs.
  `title` | string | The human readable caption of the tab.
  `description` | string | optional An additional description text for the corresponding tab pane. It is displayed as text paragraph below the tab but before the tab pane contents. If omitted, no description will be rendered.

  ##### Throws:

  Throws an exeption if a tab with the same `name` already exists.

  Type
    Error

#### inherited taboption(tabname, optionclass, classargs){LuCI.form.AbstractValue}

form.js, line 1047

  Add a configuration option widget to a tab of the section.

  Name | Type | Description
  --- | --- | ---
  `tabname` | string | The name of the section tab to add the option element to.
  `optionclass` | LuCI.form.AbstractValue | The option class to use for rendering the configuration option. Note that this value must be the class itself, not a class instance obtained from calling `new`. It must also be a class dervied from `LuCI.form.AbstractSection`.
  `classargs` | * | repeatable Additional arguments which are passed as-is to the contructor of the given option class. Refer to the class specific constructor documentation for details.

  ##### Throws:

  - Throws a `ReferenceError` exception when the given tab name does not exist.

    Type
      ReferenceError

  - Throws a `TypeError` exception in case the passed class value is not a descendent of `AbstractValue`.

    Type
      TypeError

  ##### Returns:

  Type | Description
  --- | ---
  LuCI.form.AbstractValue | Returns the instantiated option class instance.

#### inherited titleFn(property, fmt_args){string|null}

form.js, line 320

  Format the given named property as title string.

  This function looks up the given named property and formats its value suitable for use as element caption or description string. It also strips any HTML tags from the result.

  If the property value is a string, it is passed to `String.format()` along with any additional parameters passed to `titleFn()`.

  If the property value is a function, it is invoked with any additional `titleFn()` parameters as arguments and the obtained return value is converted to a string.

  In all other cases, `null` is returned.

  Name | Type | Description
  --- | --- | ---
  `property` | string | The name of the element property to use.
  `fmt_args` | * | repeatable Extra values to format the title string with.

  ##### Returns:

  Type | Description
  --- | ---
  string | null | The formatted title string or `null` if the property did not exist or was neither a string nor a function.