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Version: v5

ion-alert

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;
}

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.

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',
          handler: (blah) => {
            console.log('Confirm Cancel: blah');
          },
        },
        {
          text: 'Okay',
          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​

Descriptiontrueの場合、アラートはアニメーションで表示されます。
Attributeanimated
Typeboolean
Defaulttrue

backdropDismiss​

Descriptiontrueの場合、バックドロップがクリックされるとアラートが解除される。
Attributebackdrop-dismiss
Typeboolean
Defaulttrue

buttons​

Descriptionアラートに追加されるボタンの配列。
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​

Descriptionアラート提示時に使用するアニメーションです。
Attributeundefined
Type((baseEl: any, opts?: any) => Animation) ｜ undefined
Defaultundefined
Descriptionアラートの見出しにあるメインタイトルです。
Attributeheader
Typestring ｜ undefined
Defaultundefined

htmlAttributes​

Descriptionアラートに渡す追加属性。
Attributeundefined
TypeAlertAttributes ｜ undefined
Defaultundefined

inputs​

Descriptionアラートに表示するInputの配列。
Attributeundefined
TypeAlertInput[]
Default[]

keyboardClose​

Descriptiontrueの場合、オーバーレイが表示されたときにキーボードが自動的に解除されます。
Attributekeyboard-close
Typeboolean
Defaulttrue

leaveAnimation​

Descriptionアラートが解除されたときに使用するアニメーション。
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​

Descriptionmodeは、どのプラットフォームのスタイルを使用するかを決定します。
Attributemode
Type"ios" ｜ "md"
Defaultundefined

subHeader​

Descriptionアラートの見出しにあるサブタイトルです。タイトルの下に表示されます。
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
ionAlertDidDismissアラートが解除された後に発行されます。
ionAlertDidPresentアラートが提示された後に発行されます。
ionAlertWillDismissアラートが解除される前に発行されます。
ionAlertWillPresentアラートが提示される前に発行されます。

Methods​

dismiss​

Descriptionアラートオーバーレイが表示された後、解除します。
Signaturedismiss(data?: any, role?: string ｜ undefined) => Promise<boolean>

onDidDismiss​

Descriptionアラートが解除されたことを解決するPromiseを返します。
SignatureonDidDismiss<T = any>() => Promise<OverlayEventDetail<T>>

onWillDismiss​

Descriptionアラートが解除されるタイミングを解決するPromiseを返します。
SignatureonWillDismiss<T = any>() => Promise<OverlayEventDetail<T>>

present​

Descriptionアラートオーバーレイを作成した後に提示します。
Signaturepresent() => Promise<void>

CSS Shadow Parts​

No CSS shadow parts available for this component.

CSS Custom Properties​

NameDescription
--backdrop-opacity背景の不透明度
--background注意喚起の背景
--heightアラートの高さ
--max-heightアラートの最大の高さ
--max-widthアラートの最大幅
--min-heightアラートの最小の高さ
--min-widthアラートの最小幅
--widthアラートの幅

Slots​

No slots available for this component.

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