复选框组件

shadow

复选框允许用户从一组选项中选择多个选项。激活时，它们会显示为选中（打勾）状态。点击复选框将切换 checked 属性。也可以通过编程方式设置 checked 属性来选中它们。

基本用法

标签位置

开发者可以使用 labelPlacement 属性来控制标签相对于控件的放置位置。该属性与 flexbox 的 flex-direction 属性类似。

对齐方式

开发者可以使用 alignment 属性来控制标签和控件在交叉轴上的对齐方式。该属性与 flexbox 的 align-items 属性类似。

备注

可以使用 alignment 属性来对齐堆叠的复选框。当需要水平居中标签和控件时，这很有用。

内容分布

开发者可以使用 justify 属性来控制标签和控件在行内的分布方式。该属性与 flexbox 的 justify-content 属性类似。

备注

示例中仅使用 ion-item 来强调 justify 的工作原理。justify 正确运行并不需要它。

不确定状态复选框

标签内的链接

复选框标签有时可能需要包含链接。这些链接可以提供与复选框相关的更多信息。然而，点击链接不应选中复选框。为此，我们可以使用 stopPropagation 来阻止点击事件冒泡。采用这种方法时，标签的其余部分仍然保持可点击状态。

辅助文本与错误文本

可以通过 helperText 和 errorText 属性在复选框内部使用辅助文本和错误文本。除非将 ion-invalid 和 ion-touched 类添加到 ion-checkbox 上，否则错误文本不会显示。这确保了在用户有机会输入数据之前不会显示错误。

在 Angular 中，这通过表单验证自动完成。在 JavaScript、React 和 Vue 中，需要根据你自己的验证逻辑手动添加这些类。

主题定制

CSS 自定义属性

接口

CheckboxChangeEventDetail

interface CheckboxChangeEventDetail<T = any> {
  value: T;
  checked: boolean;
}

CheckboxCustomEvent

虽然不是必需的，但可以使用此接口替代 CustomEvent 接口，以便对该组件发出的 Ionic 事件进行更严格的类型检查。

interface CheckboxCustomEvent<T = any> extends CustomEvent {
  detail: CheckboxChangeEventDetail<T>;
  target: HTMLIonCheckboxElement;
}

属性

alignment

Description	How to control the alignment of the checkbox and label on the cross axis. "start": The label and control will appear on the left of the cross axis in LTR, and on the right side in RTL. "center": The label and control will appear at the center of the cross axis in both LTR and RTL. Setting this property will change the checkbox display to block.
Attribute	alignment
Type	"center" ｜ "start" ｜ undefined
Default	undefined

checked

Description	If true, the checkbox is selected.
Attribute	checked
Type	boolean
Default	false

color

Description	The color to use from your application's color palette. Default options are: "primary", "secondary", "tertiary", "success", "warning", "danger", "light", "medium", and "dark". For more information on colors, see theming.
Attribute	color
Type	"danger" ｜ "dark" ｜ "light" ｜ "medium" ｜ "primary" ｜ "secondary" ｜ "success" ｜ "tertiary" ｜ "warning" ｜ string ｜ undefined
Default	undefined

disabled

Description	If true, the user cannot interact with the checkbox.
Attribute	disabled
Type	boolean
Default	false

errorText

Description	Text that is placed under the checkbox label and displayed when an error is detected.
Attribute	error-text
Type	string ｜ undefined
Default	undefined

helperText

Description	Text that is placed under the checkbox label and displayed when no error is detected.
Attribute	helper-text
Type	string ｜ undefined
Default	undefined

indeterminate

Description	If true, the checkbox will visually appear as indeterminate.
Attribute	indeterminate
Type	boolean
Default	false

justify

Description	How to pack the label and checkbox within a line. "start": The label and checkbox will appear on the left in LTR and on the right in RTL. "end": The label and checkbox will appear on the right in LTR and on the left in RTL. "space-between": The label and checkbox will appear on opposite ends of the line with space between the two elements. Setting this property will change the checkbox display to block.
Attribute	justify
Type	"end" ｜ "space-between" ｜ "start" ｜ undefined
Default	undefined

labelPlacement

Description	Where to place the label relative to the checkbox. "start": The label will appear to the left of the checkbox in LTR and to the right in RTL. "end": The label will appear to the right of the checkbox in LTR and to the left in RTL. "fixed": The label has the same behavior as "start" except it also has a fixed width. Long text will be truncated with ellipses ("..."). "stacked": The label will appear above the checkbox regardless of the direction. The alignment of the label can be controlled with the alignment property.
Attribute	label-placement
Type	"end" ｜ "fixed" ｜ "stacked" ｜ "start"
Default	'start'

mode

Description	The mode determines which platform styles to use. This is a virtual property that is set once during initialization and will not update if you change its value after the initial render.
Attribute	mode
Type	"ios" ｜ "md"
Default	undefined

name

Description	The name of the control, which is submitted with the form data.
Attribute	name
Type	string
Default	this.inputId

required

Description	If true, screen readers will announce it as a required field. This property works only for accessibility purposes, it will not prevent the form from submitting if the value is invalid.
Attribute	required
Type	boolean
Default	false

value

Description	The value of the checkbox does not mean if it's checked or not, use the checked property for that. The value of a checkbox is analogous to the value of an <input type="checkbox">, it's only used when the checkbox participates in a native <form>.
Attribute	value
Type	any
Default	'on'

事件

Name	Description	Bubbles
ionBlur	Emitted when the checkbox loses focus.	true
ionChange	Emitted when the checked property has changed as a result of a user action such as a click. This event will not emit when programmatically setting the checked property.	true
ionFocus	Emitted when the checkbox has focus.	true

方法

No public methods available for this component.

CSS Shadow Parts

Name	Description
container	The container for the checkbox mark.
error-text	Supporting text displayed beneath the checkbox label when the checkbox is invalid and touched.
helper-text	Supporting text displayed beneath the checkbox label when the checkbox is valid.
label	The label text describing the checkbox.
mark	The checkmark used to indicate the checked state.
supporting-text	Supporting text displayed beneath the checkbox label.

CSS 自定义属性

iOS

Name	Description
--border-color	Border color of the checkbox icon
--border-color-checked	Border color of the checkbox icon when checked
--border-radius	Border radius of the checkbox icon
--border-style	Border style of the checkbox icon
--border-width	Border width of the checkbox icon
--checkbox-background	Background of the checkbox icon
--checkbox-background-checked	Background of the checkbox icon when checked
--checkmark-color	Color of the checkbox checkmark when checked
--checkmark-width	Stroke width of the checkbox checkmark
--size	Size of the checkbox icon
--transition	Transition of the checkbox icon

MD

Name	Description
--border-color	Border color of the checkbox icon
--border-color-checked	Border color of the checkbox icon when checked
--border-radius	Border radius of the checkbox icon
--border-style	Border style of the checkbox icon
--border-width	Border width of the checkbox icon
--checkbox-background	Background of the checkbox icon
--checkbox-background-checked	Background of the checkbox icon when checked
--checkmark-color	Color of the checkbox checkmark when checked
--checkmark-width	Stroke width of the checkbox checkmark
--size	Size of the checkbox icon
--transition	Transition of the checkbox icon

插槽

Name	Description
``	The label text to associate with the checkbox. Use the "labelPlacement" property to control where the label is placed relative to the checkbox.