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Dropdown class

📖 Description​

The Dropdown class defines a dropdown control for the Tripetto builder. It is derived from the DataControl class.

📺 Preview​

🆕 constructor​

Creates a new Dropdown instance.

Signature​

constructor(
  options:
    (IOption | IOptionGroup)[] |
    ((done: (options: IOption | IOptionGroup[]) => void) => void),
  value: any | Binding,
  style?: IDropdownStyle
): Dropdown

Parameters​

NameTypeOptionalDescription
options(IOption | IOptionGroup)[] | ((done: (options: IOption | IOptionGroup[]) => void) => void)NoSpecifies the option array or a function in case you want to load the options asynchronously.
valueany | BindingNoSpecifies the initially selected value or a data binding created with bind.
styleIDropdownStyleYesSpecifies the style (when omitted the default global style will be used).

Return value​

Returns a reference to the new Dropdown instance.

📌 Statics​

🏷️ style​

Contains the global default style for the dropdown control.

Type​

IDropdownStyle

🔧 bind​

Binds an object property to the control allowing its value to update automatically when the value of the control changes. If the control is disabled or invisible, the supplied valueWhenInactive is automatically set as the property value. When a control is enabled and visible, the supplied defaultWhenActive is set automatically if the property value is currently not defined.

Signature​

bind<Target, P extends keyof Target>(
  target: Target,
  property: P,
  valueWhenInactive: any,
  defaultWhenActive?: any,
  modifier?: (value?: any) => any
): Binding;

Parameters​

NameTypeOptionalDescription
targetTargetNoReference to the target object which contains the property.
propertyPNoSpecifies the name of the property.
valueWhenInactiveanyNoSpecifies the value which is set to the property when the control is inactive (disabled or invisible).
defaultWhenActiveanyYesSpecifies the default (initial) value that will be used when the control is active (enabled and visible).
modifier(value?: any) => anyYesSpecifies a modifier function for the data.

Return value​

Returns a Binding instance that can be used in the controls constructor to bind a value to a control.

Example​

import { Forms } from "@tripetto/builder";

const example = {
  selected: "a"
};

const dropdown = new Forms.Dropdown(
  [
    {
      label: "Option A",
      value: "a"
    },
    {
      label: "Option B",
      value: "b"
    }
  ],
  Forms.dropdown.bind(example, "selected", "a"));

🗃️ Fields​

🏷️ hasFocus​

Retrieves if the control has input focus.

Type​

boolean

🏷️ isDisabled​

Sets or retrieves if the control is disabled.

Type​

boolean

🏷️ isLocked​

Sets or retrieves if the control is locked (readonly).

Type​

boolean

🏷️ isObservable​

Retrieves if the control is observable.

Type​

boolean

🏷️ isRequired​

Sets or retrieves if the control is required.

Type​

boolean

🏷️ isVisible​

Sets or retrieves the visibility of the control.

Type​

boolean

🏷️ style​

Contains the dropdown control style.

Type​

IDropdownStyle

🏷️ value​

Sets or retrieves the selected value.

Type​

any

▶️ Methods​

🔧 blur​

Blurs the focus of the control.

Signature​

blur(): void

🔧 disable​

Disables the control.

Signature​

disable(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 disabled​

Specifies the state of the control.

Signature​

disabled(disabled?: boolean): this

Parameters​

NameTypeOptionalDescription
disabledbooleanYesSpecifies if the control is disabled (default is true).

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 enable​

Enables the control.

Signature​

enable(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 focus​

Sets the focus to the control.

Signature​

focus(): boolean

Return value​

Returns true if the focus is set.

🔧 hide​

Hides the control.

Signature​

hide(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 indent​

Enables control indentation. This can only be set during construction.

Signature​

indent(size: number): this

Parameters​

NameTypeOptionalDescription
sizenumberNoSpecifies the indent size in pixels.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 label​

Sets the label for the control.

tip

If you want to use markdown in the label, activate it first using the markdown method.

Signature​

label(label: string): this

Parameters​

NameTypeOptionalDescription
labelstringNoSpecifies the control label.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 lock​

Locks the control.

Signature​

lock(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 locked​

Specifies if the control is locked (readonly).

Signature​

locked(locked?: boolean): this

Parameters​

NameTypeOptionalDescription
lockedbooleanYesSpecifies if the control is locked/readonly (default is true).

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 markdown​

Specifies if the label should support markdown formatting.

Signature​

markdown(options?: IMarkdownOptions): this

Parameters​

NameTypeOptionalDescription
optionsIMarkdownOptionsYesSpecifies the markdown options.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 on​

Specifies the function which is invoked when the dropdown selection is changed.

Signature​

on(fn: (dropdown: Dropdown) => void): this

Parameters​

NameTypeOptionalDescription
fn(dropdown: Dropdown) => voidNoSpecifies the change function.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 optionDisabled​

Sets or retrieves the disabled state of the specified option or the current option if no option value is specified.

Signature​

optionDisabled(value?: any, disabled?: boolean): boolean

Parameters​

NameTypeOptionalDescription
valueanyYesSpecifies the option value.
disabledbooleanYesSpecifies the disabled state.

Return value​

Returns the disabled state.

🔧 optionLabel​

Sets or retrieves the label of the specified option or the current option if no option value is specified.

Signature​

optionLabel(value?: any, label?: string): string

Parameters​

NameTypeOptionalDescription
valueanyYesSpecifies the option value.
labelstringYesSpecifies a new label for the option.

Return value​

Returns the label.

🔧 options​

Sets the options for the dropdown.

Signature​

options(options: (IOption | IOptionGroup)[]): this

Parameters​

NameTypeOptionalDescription
options(IOption | IOptionGroup)[]NoSpecifies an array of options.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 placeholder​

Sets a placeholder for the control.

Signature​

placeholder(placeholder: string): this

Parameters​

NameTypeOptionalDescription
placeholderstringNoSpecifies the placeholder string.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 readonly​

Makes the control readonly.

Signature​

readonly(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 require​

Makes the control required.

Signature​

require(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 required​

Specifies if the control is required.

Signature​

required(required?: boolean): this

Parameters​

NameTypeOptionalDescription
requiredbooleanYesSpecifies if the control is required (default is true).

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 select​

Selects the specified option.

Signature​

select(value: any): this

Parameters​

NameTypeOptionalDescription
valueanyNoSpecifies the option value.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 show​

Shows the control.

Signature​

show(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 unlock​

Unlocks the control.

Signature​

unlock(): this

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 visible​

Specifies the visibility of the control.

Signature​

visible(visible?: boolean): this

Parameters​

NameTypeOptionalDescription
visiblebooleanYesSpecifies if the control is visible (default is true).

Return value​

Returns a reference to the Dropdown instance to allow chaining.

🔧 width​

Sets the width of the control.

Signature​

width(width: number | "auto" | "full"): this

Parameters​

NameTypeOptionalDescription
widthnumber | "auto" | "full"NoSpecifies the control width in pixels or sets the width to auto or full.

Return value​

Returns a reference to the Dropdown instance to allow chaining.

⛓️ Interfaces​

🔗 IDropdownStyle​

Describes the interface for the dropdown styles.

Type declaration​

interface IDropdownStyle {
  /* Dropdown appearance. */
  appearance?: IStyles;

  /* Options. */
  options?: IStyles;

  /* Option groups. */
  optGroups?: IStyles;

  /* Placeholder option. */
  placeholder?: IStyles;

  /* Dropdown label. */
  label?: IStyles;

  /* Dropdown disabled. */
  disabled?: IStyles;

  /* Dropdown required. */
  required?: IStyles;

  /* Dropdown locked. */
  locked?: IStyles;

  /* Dropdown focus. */
  focus?: IStyles;

  /* Dropdown hover. */
  hover?: IStyles;

  /* Validation passed. */
  passed?: IStyles;

  /* Validation failed. */
  failed?: IStyles;

  /* Validation awaiting. */
  awaiting?: IStyles;

  /* Dropdown when fused with form card. */
  fused?: {
    /* Dropdown appearance. */
    appearance?: IStyles;

    /* Dropdown label. */
    label?: IStyles;

    /* Dropdown required. */
    required?: IStyles;

    /* Dropdown locked. */
    locked?: IStyles;

    /* Dropdown focus. */
    focus?: IStyles;

    /* Dropdown hover. */
    hover?: IStyles;

    /* Validation passed. */
    passed?: IStyles;

    /* Validation failed. */
    failed?: IStyles;

    /* Validation awaiting. */
    awaiting?: IStyles;
  };
}

🔗 IOption​

Describes the interface for a dropdown option.

Type declaration​

interface IOption {
  /* Label for the option. */
  label: string;

  /* Value for the option. */
  value: any;

  /* Specifies if the option is disabled. */
  disabled?: boolean;

  /* Specifies an indentation level for an option. */
  indent?: number;
}

🔗 IOptionGroup​

Describes the interface for a dropdown option group.

Type declaration​

interface IOptionGroup {
  /* Label for the option group. */
  optGroup: string;
}