Image

A React component for displaying different types of images, including network images, static resources, temporary local images, and images from local disk, such as the camera roll.

This example shows fetching and displaying an image from local storage as well as one from network and even from data provided in the 'data:' uri scheme.

Note that for network and data images, you will need to manually specify the dimensions of your image!

Examples

import React from "react";
import { View, Image, StyleSheet } from "tbox/ui";

const styles = StyleSheet.create({
  container: {
    paddingTop: 50,
  },
  tinyLogo: {
    width: 50,
    height: 50,
  },
  logo: {
    width: 66,
    height: 58,
  },
});

const DisplayAnImage = () => {
  return (
    <View style={styles.container}>
      <Image
        style={styles.tinyLogo}
        source={require("@expo/snack-static/react-native-logo.png")}
      />
      <Image
        style={styles.tinyLogo}
        source={{
          uri: "https://reactnative.dev/img/tiny_logo.png",
        }}
      />
      <Image
        style={styles.logo}
        source={{
          uri:
            "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADMAAAAzCAYAAAA6oTAqAAAAEXRFWHRTb2Z0d2FyZQBwbmdjcnVzaEB1SfMAAABQSURBVGje7dSxCQBACARB+2/ab8BEeQNhFi6WSYzYLYudDQYGBgYGBgYGBgYGBgYGBgZmcvDqYGBgmhivGQYGBgYGBgYGBgYGBgYGBgbmQw+P/eMrC5UTVAAAAABJRU5ErkJggg==",
        }}
      />
    </View>
  );
};

export default DisplayAnImage;

You can also add style to an image:

import React from "react";
import { View, Image, StyleSheet } from "tbox/ui";

const styles = StyleSheet.create({
  container: {
    paddingTop: 50,
  },
  stretch: {
    width: 50,
    height: 200,
    resizeMode: "stretch",
  },
});

const DisplayAnImageWithStyle = () => {
  return (
    <View style={styles.container}>
      <Image
        style={styles.stretch}
        source={require("@expo/snack-static/react-native-logo.png")}
      />
    </View>
  );
};

export default DisplayAnImageWithStyle;

GIF and WebP support on Android

When building your own native code, GIF and WebP are not supported by default on Android.

You will need to add some optional modules in android/app/build.gradle, depending on the needs of your app.

dependencies {
  // If your app supports Android versions before Ice Cream Sandwich (API level 14)
  implementation 'com.facebook.fresco:animated-base-support:1.3.0'

  // For animated GIF support
  implementation 'com.facebook.fresco:animated-gif:2.0.0'

  // For WebP support, including animated WebP
  implementation 'com.facebook.fresco:animated-webp:2.1.0'
  implementation 'com.facebook.fresco:webpsupport:2.0.0'

  // For WebP support, without animations
  implementation 'com.facebook.fresco:webpsupport:2.0.0'
}

Reference

Props

`style`

ImageResizeMode is an Enum for different image resizing modes, set via the resizeMode style property on Image components. The values are contain, cover, stretch, center, repeat.

Type	Required
style	No

`accessible`

When true, indicates the image is an accessibility element.

Type	Required	Platform
bool	No	iOS

`accessibilityLabel`

The text that's read by the screen reader when the user interacts with the image.

Type	Required	Platform
string	No	iOS

`blurRadius`

blurRadius: the blur radius of the blur filter added to the image

Type	Required
number	No

Tip : IOS you will need to increase blurRadius more than 5

`capInsets`

When the image is resized, the corners of the size specified by capInsets will stay a fixed size, but the center content and borders of the image will be stretched. This is useful for creating resizable rounded buttons, shadows, and other resizable assets. More info in the official Apple documentation.

Type	Required	Platform
Rect	No	iOS

`defaultSource`

A static image to display while loading the image source.

Type	Required	Platform
object, number	No	iOS
number	No	Android

If passing an object, the general shape is {uri: string, width: number, height: number, scale: number}:

uri - a string representing the resource identifier for the image, which should be either a local file path or the name of a static image resource (which should be wrapped in the require('./path/to/image.png') function).
width, height - can be specified if known at build time, in which case these will be used to set the default <Image/> component dimensions.
scale - used to indicate the scale factor of the image. Defaults to 1.0 if unspecified, meaning that one image pixel equates to one display point / DIP.

If passing a number:

number - Opaque type returned by something like require('./image.jpg').

Note: On Android, the default source prop is ignored on debug builds.

`fadeDuration`

Android only. By default, it is 300ms.

Type	Required	Platform
number	No	Android

`loadingIndicatorSource`

Similarly to source, this property represents the resource used to render the loading indicator for the image, displayed until image is ready to be displayed, typically after when it got downloaded from network.

Type	Required
array of ImageSourcePropTypes, number	No

Can accept a number as returned by require('./image.jpg')

`onError`

Invoked on load error with {nativeEvent: {error}}.

Type	Required
function	No

`onLayout`

Invoked on mount and layout changes with {nativeEvent: {layout: {x, y, width, height}}}.

Type	Required
function	No

`onLoad`

Invoked when load completes successfully.

Type	Required
function	No

`onLoadEnd`

Invoked when load either succeeds or fails.

Type	Required
function	No

`onLoadStart`

Invoked on load start.

e.g., onLoadStart={(e) => this.setState({loading: true})}

Type	Required
function	No

`onPartialLoad`

Invoked when a partial load of the image is complete. The definition of what constitutes a "partial load" is loader specific though this is meant for progressive JPEG loads.

Type	Required	Platform
function	No	iOS

`onProgress`

Invoked on download progress with {nativeEvent: {loaded, total}}.

Type	Required	Platform
function	No	iOS

`progressiveRenderingEnabled`

Android only. When true, enables progressive jpeg streaming. https://frescolib.org/docs/progressive-jpegs.html

Type	Required	Platform
bool	No	Android

`resizeMethod`

The mechanism that should be used to resize the image when the image's dimensions differ from the image view's dimensions. Defaults to auto.

auto: Use heuristics to pick between resize and scale.
resize: A software operation which changes the encoded image in memory before it gets decoded. This should be used instead of scale when the image is much larger than the view.
scale: The image gets drawn downscaled or upscaled. Compared to resize, scale is faster (usually hardware accelerated) and produces higher quality images. This should be used if the image is smaller than the view. It should also be used if the image is slightly bigger than the view.

More details about resize and scale can be found at http://frescolib.org/docs/resizing.html.

Type	Required	Platform
enum('auto', 'resize', 'scale')	No	Android

`resizeMode`

Determines how to resize the image when the frame doesn't match the raw image dimensions. Defaults to cover.

cover: Scale the image uniformly (maintain the image's aspect ratio) so that both dimensions (width and height) of the image will be equal to or larger than the corresponding dimension of the view (minus padding).
contain: Scale the image uniformly (maintain the image's aspect ratio) so that both dimensions (width and height) of the image will be equal to or less than the corresponding dimension of the view (minus padding).
stretch: Scale width and height independently, This may change the aspect ratio of the src.
repeat: Repeat the image to cover the frame of the view. The image will keep its size and aspect ratio, unless it is larger than the view, in which case it will be scaled down uniformly so that it is contained in the view.
center: Center the image in the view along both dimensions. If the image is larger than the view, scale it down uniformly so that it is contained in the view.

Type	Required
enum('cover', 'contain', 'stretch', 'repeat', 'center')	No

`source`

The image source (either a remote URL or a local file resource).

This prop can also contain several remote URLs, specified together with their width and height and potentially with scale/other URI arguments. The native side will then choose the best uri to display based on the measured size of the image container. A cache property can be added to control how networked request interacts with the local cache. (For more information see Cache Control for Images).

The currently supported formats are png, jpg, jpeg, bmp, gif, webp (Android only), psd (iOS only). In addition, iOS supports several RAW image formats. Refer to Apple's documentation for the current list of supported camera models (for iOS 12, see https://support.apple.com/en-ca/HT208967).

Type	Required
ImageSourcePropType	No

`testID`

A unique identifier for this element to be used in UI Automation testing scripts.

Type	Required
string	No

Methods

`getSize()`

Image.getSize(uri, success, [failure]);

Retrieve the width and height (in pixels) of an image prior to displaying it. This method can fail if the image cannot be found, or fails to download.

In order to retrieve the image dimensions, the image may first need to be loaded or downloaded, after which it will be cached. This means that in principle you could use this method to preload images, however it is not optimized for that purpose, and may in future be implemented in a way that does not fully load/download the image data. A proper, supported way to preload images will be provided as a separate API.

Parameters:

Name	Type	Required	Description
uri	string	Yes	The location of the image.
success	function	Yes	The function that will be called if the image was successfully found and width and height retrieved.
failure	function	No	The function that will be called if there was an error, such as failing to retrieve the image.

`getSizeWithHeaders()`

Image.getSizeWithHeaders(uri, headers, success, [failure]);

Retrieve the width and height (in pixels) of an image prior to displaying it with the ability to provide the headers for the request. This method can fail if the image cannot be found, or fails to download.

Does not work for static image resources.

Parameters:

Name	Type	Required	Description
uri	string	Yes	The location of the image.
headers	object	Yes	The headers for the request.
success	function	Yes	The function that will be called if the image was successfully found and width and height retrieved.
failure	function	No	The function that will be called if there was an error, such as failing toto retrieve the image.

`prefetch()`

Image.prefetch(url);

Prefetches a remote image for later use by downloading it to the disk cache

Parameters:

Name	Type	Required	Description
url	string	Yes	The remote location of the image.

`abortPrefetch()`

Image.abortPrefetch(requestId);

Abort prefetch request. Android-only.

Parameters:

Name	Type	Required	Description
requestId	number	Yes	Id as returned by prefetch()

`queryCache()`

Image.queryCache(urls);

Perform cache interrogation. Returns a mapping from URL to cache status, such as "disk" or "memory". If a requested URL is not in the mapping, it means it's not in the cache.

Parameters:

Name	Type	Required	Description
urls	array	Yes	List of image URLs to check the cache for.

`resolveAssetSource()`

Image.resolveAssetSource(source);

Resolves an asset reference into an object which has the properties uri, width, and height.

Parameters:

Name	Type	Required	Description
source	number, object	Yes	A number (opaque type returned by require('./foo.png')) or an `ImageSource`.

ImageSource is an object like { uri: '<http location || file path>' }

Examples#

GIF and WebP support on Android#

Reference#

Props#

style#

accessible#

accessibilityLabel#

blurRadius#

capInsets#

defaultSource#

fadeDuration#

loadingIndicatorSource#

onError#

onLayout#

onLoad#

onLoadEnd#

onLoadStart#

onPartialLoad#

onProgress#

progressiveRenderingEnabled#

resizeMethod#

resizeMode#

source#

testID#

Methods#

getSize()#

getSizeWithHeaders()#

prefetch()#

abortPrefetch()#

queryCache()#

resolveAssetSource()#

Examples

GIF and WebP support on Android

Reference

Props

`style`

`accessible`

`accessibilityLabel`

`blurRadius`

`capInsets`

`defaultSource`

`fadeDuration`

`loadingIndicatorSource`

`onError`

`onLayout`

`onLoad`

`onLoadEnd`

`onLoadStart`

`onPartialLoad`

`onProgress`

`progressiveRenderingEnabled`

`resizeMethod`

`resizeMode`

`source`

`testID`

Methods

`getSize()`

`getSizeWithHeaders()`

`prefetch()`

`abortPrefetch()`

`queryCache()`

`resolveAssetSource()`