ion-img
Img is a tag that will lazily load an image when ever the tag is in the viewport. This is extremely useful when generating a large list as images are only loaded when they're visible. The component uses Intersection Observer internally, which is supported in most modern browser, but falls back to a setTimeout
when it is not supported.
Usage
- ANGULAR
- REACT
- STENCIL
- VUE
<ion-list>
<ion-item *ngFor="let item of items">
<ion-thumbnail slot="start">
<ion-img [src]="item.src"></ion-img>
</ion-thumbnail>
<ion-label>{{item.text}}</ion-label>
</ion-item>
</ion-list>
import React from 'react';
import { IonList, IonItem, IonThumbnail, IonImg, IonLabel, IonContent } from '@ionic/react';
type Item = {
src: string;
text: string;
};
const items: Item[] = [{ src: 'http://placekitten.com/g/200/300', text: 'a picture of a cat' }];
export const ImgExample: React.FC = () => (
<IonContent>
<IonList>
{items.map((image, i) => (
<IonItem key={i}>
<IonThumbnail slot="start">
<IonImg src={image.src} />
</IonThumbnail>
<IonLabel>{image.text}</IonLabel>
</IonItem>
))}
</IonList>
</IonContent>
);
import { Component, h } from '@stencil/core';
@Component({
tag: 'img-example',
styleUrl: 'img-example.css',
})
export class ImgExample {
private items = [
{
text: 'Item 1',
src: '/path/to/external/file.png',
},
{
text: 'Item 2',
src: '/path/to/external/file.png',
},
{
text: 'Item 3',
src: '/path/to/external/file.png',
},
];
render() {
return [
<ion-list>
{this.items.map((item) => (
<ion-item>
<ion-thumbnail slot="start">
<ion-img src={item.src}></ion-img>
</ion-thumbnail>
<ion-label>{item.text}</ion-label>
</ion-item>
))}
</ion-list>,
];
}
}
<template>
<ion-list>
<ion-item v-for="item in items" :key="item.src">
<ion-thumbnail slot="start">
<ion-img :src="item.src"></ion-img>
</ion-thumbnail>
<ion-label>{{item.text}}</ion-label>
</ion-item>
</ion-list>
</template>
<script>
import { IonImg, IonItem, IonLabel, IonList, IonThumbnail } from '@ionic/vue';
import { defineComponent } from 'vue';
export default defineComponent({
components: { IonImg, IonItem, IonLabel, IonList, IonThumbnail },
setup() {
const items = [
{
text: 'Item 1',
src: '/path/to/external/file.png',
},
{
text: 'Item 2',
src: '/path/to/external/file.png',
},
{
text: 'Item 3',
src: '/path/to/external/file.png',
},
];
return { items };
},
});
</script>
Properties
alt
Description | This attribute defines the alternative text describing the image. Users will see this text displayed if the image URL is wrong, the image is not in one of the supported formats, or if the image is not yet downloaded. |
Attribute | alt |
Type | string | undefined |
Default | undefined |
src
Description | The image URL. This attribute is mandatory for the <img> element. |
Attribute | src |
Type | string | undefined |
Default | undefined |
Events
Name | Description |
---|---|
ionError | Emitted when the img fails to load |
ionImgDidLoad | Emitted when the image has finished loading |
ionImgWillLoad | Emitted when the img src has been set |
Methods
No public methods available for this component.
CSS Shadow Parts
Name | Description |
---|---|
image | The inner img element. |
CSS Custom Properties
No CSS custom properties available for this component.
Slots
No slots available for this component.