Flutter教程

ion-textarea

概要(CONTENTS)

Ionic4项目中我们可以使用Ionic4组件ion-textarea对项目进行布局。

ion-textarea官方文档地址:https://ionicframework.com/docs/api/textarea

The textarea component is used for multi-line text input. A native textarea element is rendered inside of the component. The user experience and interactivity of the textarea component is improved by having control over the native textarea.

Unlike the native textarea element, the Ionic textarea does not support loading its value from the inner content. The textarea value should be set in the value attribute.

The textarea component accepts the native textarea attributes in addition to the Ionic properties.

ion-textarea 用法(Usage)


<ion-textarea>ion-textarea>


<ion-item>
  <ion-textarea placeholder="Enter more information here...">ion-textarea>
ion-item>


<ion-item>
  <ion-label position="floating">Descriptionion-label>
  <ion-textarea>ion-textarea>
ion-item>


<ion-item>
  <ion-label position="stacked">Summaryion-label>
  <ion-textarea
    disabled
    readonly
    value="Ionic enables developers to build performant, high-quality mobile apps.">
  ion-textarea>
ion-item>


<ion-item>
  <ion-label>Commention-label>
  <ion-textarea clearOnEdit="true">ion-textarea>
ion-item>


<ion-item>
  <ion-label>Notesion-label>
  <ion-textarea rows="6" cols="20" placeholder="Enter any notes here...">ion-textarea>
ion-item>

<ion-textarea>ion-textarea>


<ion-item>
  <ion-textarea placeholder="Enter more information here...">ion-textarea>
ion-item>


<ion-item>
  <ion-label position="floating">Descriptionion-label>
  <ion-textarea>ion-textarea>
ion-item>


<ion-item>
  <ion-label position="stacked">Summaryion-label>
  <ion-textarea
    disabled
    readonly
    value="Ionic enables developers to build performant, high-quality mobile apps.">
  ion-textarea>
ion-item>


<ion-item>
  <ion-label>Commention-label>
  <ion-textarea clear-on-edit="true">ion-textarea>
ion-item>


<ion-item>
  <ion-label>Notesion-label>
  <ion-textarea rows="6" cols="20" placeholder="Enter any notes here...">ion-textarea>
ion-item>
import React from 'react';

import { IonTextarea, IonItem, IonLabel } from '@ionic/react';

const Example: React.SFC<{}> = () => (
  <>
    {/*-- Default textarea --*/}
    <IonTextarea>IonTextarea>

    {/*-- Textarea in an item with a placeholder --*/}
    <IonItem>
      <IonTextarea placeholder="Enter more information here...">IonTextarea>
    IonItem>

    {/*-- Textarea in an item with a floating label --*/}
    <IonItem>
      <IonLabel position="floating">DescriptionIonLabel>
      <IonTextarea>IonTextarea>
    IonItem>

    {/*-- Disabled and readonly textarea in an item with a stacked label --*/}
    <IonItem>
      <IonLabel position="stacked">SummaryIonLabel>
      <IonTextarea
        disabled
        readonly
        value="Ionic enables developers to build performant, high-quality mobile apps.">
      IonTextarea>
    IonItem>

    {/*-- Textarea that clears the value on edit --*/}
    <IonItem>
      <IonLabel>CommentIonLabel>
      <IonTextarea clearOnEdit={true}>IonTextarea>
    IonItem>

    {/*-- Textarea with custom number of rows and cols --*/}
    <IonItem>
      <IonLabel>NotesIonLabel>
      <IonTextarea rows={6} cols={20} placeholder="Enter any notes here...">IonTextarea>
    IonItem>
  >
);

export default Example;
<template>
  
  <ion-textarea>ion-textarea>

  
  <ion-item>
    <ion-textarea placeholder="Enter more information here...">ion-textarea>
  ion-item>

  
  <ion-item>
    <ion-label position="floating">Descriptionion-label>
    <ion-textarea>ion-textarea>
  ion-item>

  
  <ion-item>
    <ion-label position="stacked">Summaryion-label>
    <ion-textarea
      disabled
      readonly
      value="Ionic enables developers to build performant, high-quality mobile apps.">
    ion-textarea>
  ion-item>

  
  <ion-item>
    <ion-label>Commention-label>
    <ion-textarea clearOnEdit="true">ion-textarea>
  ion-item>

  
  <ion-item>
    <ion-label>Notesion-label>
    <ion-textarea rows="6" cols="20" placeholder="Enter any notes here...">ion-textarea>
  ion-item>
template>

ion-textarea 属性(Properties)

autoGrow

Description

If true, the element height will increase based on the value.

Attribute auto-grow
Type boolean
Default false

autocapitalize

Description

Indicates whether and how the text value should be automatically capitalized as it is entered/edited by the user.

Attribute autocapitalize
Type string
Default 'none'

autofocus

Description

This Boolean attribute lets you specify that a form control should have input focus when the page loads.

Attribute autofocus
Type boolean
Default false

clearOnEdit

Description

If true, the value will be cleared after focus upon edit. Defaults to true when type is "password", false for all other types.

Attribute clear-on-edit
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 string | undefined

cols

Description

The visible width of the text control, in average character widths. If it is specified, it must be a positive integer.

Attribute cols
Type number | undefined

debounce

Description

Set the amount of time, in milliseconds, to wait to trigger the ionChange event after each keystroke.

Attribute debounce
Type number
Default 0

disabled

Description

If true, the user cannot interact with the textarea.

Attribute disabled
Type boolean
Default false

maxlength

Description

If the value of the type attribute is text, email, search, password, tel, or url, this attribute specifies the maximum number of characters that the user can enter.

Attribute maxlength
Type number | undefined

minlength

Description

If the value of the type attribute is text, email, search, password, tel, or url, this attribute specifies the minimum number of characters that the user can enter.

Attribute minlength
Type number | undefined

mode

Description

The mode determines which platform styles to use.

Attribute mode
Type "ios" | "md"

name

Description

The name of the control, which is submitted with the form data.

Attribute name
Type string
Default this.inputId

placeholder

Description

Instructional text that shows before the input has a value.

Attribute placeholder
Type null | string | undefined

readonly

Description

If true, the user cannot modify the value.

Attribute readonly
Type boolean
Default false

required

Description

If true, the user must fill in a value before submitting a form.

Attribute required
Type boolean
Default false

rows

Description

The number of visible text lines for the control.

Attribute rows
Type number | undefined

spellcheck

Description

If true, the element will have its spelling and grammar checked.

Attribute spellcheck
Type boolean
Default false

value

Description

The value of the textarea.

Attribute value
Type null | string | undefined
Default ''

wrap

Description

Indicates how the control wraps text.

Attribute wrap
Type "hard" | "off" | "soft" | undefined

ion-textarea 事件(Events)

Name Description
ionBlur Emitted when the input loses focus.
ionChange Emitted when the input value has changed.
ionFocus Emitted when the input has focus.
ionInput Emitted when a keyboard input ocurred.

ion-textarea 内置方法(Methods)

getInputElement

Description

Returns the native