Skip to main content
Version: v6

ion-alert

scoped

Contents

An Alert is a dialog that presents users with information or collects information from the user using inputs. An alert appears on top of the app's content, and must be manually dismissed by the user before they can resume interaction with the app. It can also optionally have a header, subHeader and message.

Buttons

In the array of buttons, each button includes properties for its text, and optionally a handler. If a handler returns false then the alert will not automatically be dismissed when the button is clicked. All buttons will show up in the order they have been added to the buttons array from left to right. Note: The right most button (the last one in the array) is the main button.

Optionally, a role property can be added to a button, such as cancel. If a cancel role is on one of the buttons, then if the alert is dismissed by tapping the backdrop, then it will fire the handler from the button with a cancel role.

Inputs

Alerts can also include several different inputs whose data can be passed back to the app. Inputs can be used as a simple way to prompt users for information. Radios, checkboxes and text inputs are all accepted, but they cannot be mixed. For example, an alert could have all radio button inputs, or all checkbox inputs, but the same alert cannot mix radio and checkbox inputs. Do note however, different types of "text" inputs can be mixed, such as url, email, text, textarea etc. If you require a complex form UI which doesn't fit within the guidelines of an alert then we recommend building the form within a modal instead.

Customization

Alert uses scoped encapsulation, which means it will automatically scope its CSS by appending each of the styles with an additional class at runtime. Overriding scoped selectors in CSS requires a higher specificity selector.

We recommend passing a custom class to cssClass in the create method and using that to add custom styles to the host and inner elements. This property can also accept multiple classes separated by spaces. View the Usage section for an example of how to pass a class using cssClass.

/* DOES NOT WORK - not specific enough */
.alert-wrapper {
background: #e5e5e5;
}

/* Works - pass "my-custom-class" in cssClass to increase specificity */
.my-custom-class .alert-wrapper {
background: #e5e5e5;
}

Any of the defined CSS Custom Properties can be used to style the Alert without needing to target individual elements:

.my-custom-class {
--background: #e5e5e5;
}
note

If you are building an Ionic Angular app, the styles need to be added to a global stylesheet file. Read Style Placement in the Angular section below for more information.

Interfaces

AlertButton

interface AlertButton {
text: string;
role?: 'cancel' | 'destructive' | string;
cssClass?: string | string[];
handler?: (value: any) => boolean | void | {[key: string]: any};
}

AlertInput

interface AlertInput {
type?: TextFieldTypes | 'checkbox' | 'radio' | 'textarea';
name?: string;
placeholder?: string;
value?: any;
label?: string;
checked?: boolean;
disabled?: boolean;
id?: string;
handler?: (input: AlertInput) => void;
min?: string | number;
max?: string | number;
cssClass?: string | string[];
attributes?: { [key: string]: any };
tabindex?: number;
}

AlertOptions

interface AlertOptions {
header?: string;
subHeader?: string;
message?: string | IonicSafeString;
cssClass?: string | string[];
inputs?: AlertInput[];
buttons?: (AlertButton | string)[];
backdropDismiss?: boolean;
translucent?: boolean;
animated?: boolean;
htmlAttributes?: { [key: string]: any };

mode?: Mode;
keyboardClose?: boolean;
id?: string;

enterAnimation?: AnimationBuilder;
leaveAnimation?: AnimationBuilder;
}

Usage

import { Component } from '@angular/core';
import { AlertController } from '@ionic/angular';

@Component({
selector: 'alert-example',
templateUrl: 'alert-example.html',
styleUrls: ['./alert-example.css'],
})
export class AlertExample {

constructor(public alertController: AlertController) {}

async presentAlert() {
const alert = await this.alertController.create({
cssClass: 'my-custom-class',
header: 'Alert',
subHeader: 'Subtitle',
message: 'This is an alert message.',
buttons: ['OK']
});

await alert.present();

const { role } = await alert.onDidDismiss();
console.log('onDidDismiss resolved with role', role);
}

async presentAlertMultipleButtons() {
const alert = await this.alertController.create({
cssClass: 'my-custom-class',
header: 'Alert',
subHeader: 'Subtitle',
message: 'This is an alert message.',
buttons: ['Cancel', 'Open Modal', 'Delete']
});

await alert.present();
}

async presentAlertConfirm() {
const alert = await this.alertController.create({
cssClass: 'my-custom-class',
header: 'Confirm!',
message: 'Message <strong>text</strong>!!!',
buttons: [
{
text: 'Cancel',
role: 'cancel',
cssClass: 'secondary',
id: 'cancel-button',
handler: (blah) => {
console.log('Confirm Cancel: blah');
}
}, {
text: 'Okay',
id: 'confirm-button',
handler: () => {
console.log('Confirm Okay');
}
}
]
});

await alert.present();
}

async presentAlertPrompt() {
const alert = await this.alertController.create({
cssClass: 'my-custom-class',
header: 'Prompt!',
inputs: [
{
name: 'name1',
type: 'text',
placeholder: 'Placeholder 1'
},
{
name: 'name2',
type: 'text',
id: 'name2-id',
value: 'hello',
placeholder: 'Placeholder 2'
},
// multiline input.
{
name: 'paragraph',
id: 'paragraph',
type: 'textarea',
placeholder: 'Placeholder 3'
},
{
name: 'name3',
value: 'http://ionicframework.com',
type: 'url',
placeholder: 'Favorite site ever'
},
// input date with min & max
{
name: 'name4',
type: 'date',
min: '2017-03-01',
max: '2018-01-12'
},
// input date without min nor max
{
name: 'name5',
type: 'date'
},
{
name: 'name6',
type: 'number',
min: -5,
max: 10
},
{
name: 'name7',
type: 'number'
},
{
name: 'name8',
type: 'password',
placeholder: 'Advanced Attributes',
cssClass: 'specialClass',
attributes: {
maxlength: 4,
inputmode: 'decimal'
}
}
],
buttons: [
{
text: 'Cancel',
role: 'cancel',
cssClass: 'secondary',
handler: () => {
console.log('Confirm Cancel');
}
}, {
text: 'Ok',
handler: () => {
console.log('Confirm Ok');
}
}
]
});

await alert.present();
}

async presentAlertRadio() {
const alert = await this.alertController.create({
cssClass: 'my-custom-class',
header: 'Radio',
inputs: [
{
name: 'radio1',
type: 'radio',
label: 'Radio 1',
value: 'value1',
handler: () => {
console.log('Radio 1 selected');
},
checked: true
},
{
name: 'radio2',
type: 'radio',
label: 'Radio 2',
value: 'value2',
handler: () => {
console.log('Radio 2 selected');
}
},
{
name: 'radio3',
type: 'radio',
label: 'Radio 3',
value: 'value3',
handler: () => {
console.log('Radio 3 selected');
}
},
{
name: 'radio4',
type: 'radio',
label: 'Radio 4',
value: 'value4',
handler: () => {
console.log('Radio 4 selected');
}
},
{
name: 'radio5',
type: 'radio',
label: 'Radio 5',
value: 'value5',
handler: () => {
console.log('Radio 5 selected');
}
},
{
name: 'radio6',
type: 'radio',
label: 'Radio 6 Radio 6 Radio 6 Radio 6 Radio 6 Radio 6 Radio 6 Radio 6 Radio 6 Radio 6 ',
value: 'value6',
handler: () => {
console.log('Radio 6 selected');
}
}
],
buttons: [
{
text: 'Cancel',
role: 'cancel',
cssClass: 'secondary',
handler: () => {
console.log('Confirm Cancel');
}
}, {
text: 'Ok',
handler: () => {
console.log('Confirm Ok');
}
}
]
});

await alert.present();
}

async presentAlertCheckbox() {
const alert = await this.alertController.create({
cssClass: 'my-custom-class',
header: 'Checkbox',
inputs: [
{
name: 'checkbox1',
type: 'checkbox',
label: 'Checkbox 1',
value: 'value1',
handler: () => {
console.log('Checkbox 1 selected');
},
checked: true
},

{
name: 'checkbox2',
type: 'checkbox',
label: 'Checkbox 2',
value: 'value2',
handler: () => {
console.log('Checkbox 2 selected');
}
},

{
name: 'checkbox3',
type: 'checkbox',
label: 'Checkbox 3',
value: 'value3',
handler: () => {
console.log('Checkbox 3 selected');
}
},

{
name: 'checkbox4',
type: 'checkbox',
label: 'Checkbox 4',
value: 'value4',
handler: () => {
console.log('Checkbox 4 selected');
}
},

{
name: 'checkbox5',
type: 'checkbox',
label: 'Checkbox 5',
value: 'value5',
handler: () => {
console.log('Checkbox 5 selected');
}
},

{
name: 'checkbox6',
type: 'checkbox',
label: 'Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6 Checkbox 6',
value: 'value6',
handler: () => {
console.log('Checkbox 6 selected');
}
}
],
buttons: [
{
text: 'Cancel',
role: 'cancel',
cssClass: 'secondary',
handler: () => {
console.log('Confirm Cancel');
}
}, {
text: 'Ok',
handler: () => {
console.log('Confirm Ok');
}
}
]
});

await alert.present();
}
}

Style Placement

In Angular, the CSS of a specific page is scoped only to elements of that page. Even though the Alert can be presented from within a page, the ion-alert element is appended outside of the current page. This means that any custom styles need to go in a global stylesheet file. In an Ionic Angular starter this can be the src/global.scss file or you can register a new global style file by adding to the styles build option in angular.json.

Properties

animated

DescriptionIf true, the alert will animate.
Attributeanimated
Typeboolean
Defaulttrue

backdropDismiss

DescriptionIf true, the alert will be dismissed when the backdrop is clicked.
Attributebackdrop-dismiss
Typeboolean
Defaulttrue

buttons

DescriptionArray of buttons to be added to the alert.
Attributeundefined
Type(string | AlertButton)[]
Default[]

cssClass

DescriptionAdditional classes to apply for custom CSS. If multiple classes are provided they should be separated by spaces.
Attributecss-class
Typestring | string[] | undefined
Defaultundefined

enterAnimation

DescriptionAnimation to use when the alert is presented.
Attributeundefined
Type((baseEl: any, opts?: any) => Animation) | undefined
Defaultundefined
DescriptionThe main title in the heading of the alert.
Attributeheader
Typestring | undefined
Defaultundefined

htmlAttributes

DescriptionAdditional attributes to pass to the alert.
Attributeundefined
TypeAlertAttributes | undefined
Defaultundefined

inputs

DescriptionArray of input to show in the alert.
Attributeundefined
TypeAlertInput[]
Default[]

keyboardClose

DescriptionIf true, the keyboard will be automatically dismissed when the overlay is presented.
Attributekeyboard-close
Typeboolean
Defaulttrue

leaveAnimation

DescriptionAnimation to use when the alert is dismissed.
Attributeundefined
Type((baseEl: any, opts?: any) => Animation) | undefined
Defaultundefined

message

DescriptionThe main message to be displayed in the alert. message can accept either plaintext or HTML as a string. To display characters normally reserved for HTML, they must be escaped. For example <Ionic> would become &lt;Ionic&gt;

For more information: Security Documentation
Attributemessage
TypeIonicSafeString | string | undefined
Defaultundefined

mode

DescriptionThe mode determines which platform styles to use.
Attributemode
Type"ios" | "md"
Defaultundefined

subHeader

DescriptionThe subtitle in the heading of the alert. Displayed under the title.
Attributesub-header
Typestring | undefined
Defaultundefined

translucent

DescriptionIf true, the alert will be translucent. Only applies when the mode is "ios" and the device supports backdrop-filter.
Attributetranslucent
Typeboolean
Defaultfalse

Events

NameDescription
ionAlertDidDismissEmitted after the alert has dismissed.
ionAlertDidPresentEmitted after the alert has presented.
ionAlertWillDismissEmitted before the alert has dismissed.
ionAlertWillPresentEmitted before the alert has presented.

Methods

dismiss

DescriptionDismiss the alert overlay after it has been presented.
Signaturedismiss(data?: any, role?: string | undefined) => Promise<boolean>

onDidDismiss

DescriptionReturns a promise that resolves when the alert did dismiss.
SignatureonDidDismiss<T = any>() => Promise<OverlayEventDetail<T>>

onWillDismiss

DescriptionReturns a promise that resolves when the alert will dismiss.
SignatureonWillDismiss<T = any>() => Promise<OverlayEventDetail<T>>

present

DescriptionPresent the alert overlay after it has been created.
Signaturepresent() => Promise<void>

CSS Custom Properties

NameDescription
--backdrop-opacityOpacity of the backdrop
--backgroundBackground of the alert
--heightHeight of the alert
--max-heightMaximum height of the alert
--max-widthMaximum width of the alert
--min-heightMinimum height of the alert
--min-widthMinimum width of the alert
--widthWidth of the alert
View Source