Image

The <Image> component is usually used to display images in applications. It supports images in PNG, JPG, BMP, SVG, or GIF format from the following data sources: PixelMap, ResourceStr, or DrawableDescriptor.

NOTE

This component is supported since API version 7. Updates will be marked with a superscript to indicate their earliest API version.

Required Permissions

To use online images, the application must have the ohos.permission.INTERNET permission. For details about how to apply for a permission, see Declaring Permissions.

Child Components

Not supported

APIs

Image(src: PixelMap|ResourceStr|DrawableDescriptor)

Obtains an image from the specified source for subsequent rendering and display.

If the <Image> component fails to obtain the image or the obtained image size is 0, the <Image> component is automatically resized to 0 and does not follow the layout constraints of its parent component.

Since API version 9, this API is supported in ArkTS widgets.

Parameters

Attributes

For details about how to use attributes, see Setting Attributes. In addition to the universal attributes, the following attributes are supported.

Name	Type	Description
alt	string |Resource	Placeholder image displayed during loading. Local images (in PNG, JPG, BMP, SVG, or GIF format) are supported. Online images are not supported. Default value: null Since API version 9, this API is supported in ArkTS widgets.
objectFit	ImageFit	How the image is resized to fit its container. Default value: ImageFit.Cover Since API version 9, this API is supported in ArkTS widgets.
objectRepeat	ImageRepeat	How the image is repeated. When set to repeat, the image is repeated from the center to edges. The last image will be clipped if it does not fit in the component. Default value: ImageRepeat.NoRepeat Since API version 9, this API is supported in ArkTS widgets. NOTE This attribute is not applicable to SVG images.
interpolation	ImageInterpolation	Interpolation effect of the image, which can alleviate aliasing that occurs when the image is zoomed. Default value: ImageInterpolation.None Since API version 9, this API is supported in ArkTS widgets. NOTE When the image is zoomed out, high quality interpolation is not applicable. You are advised to use medium or low quality interpolation instead. This attribute is not applicable to SVG images.
renderMode	ImageRenderMode	Rendering mode of the image, which can be Original or Template (monochrome). Default value: ImageRenderMode.Original Since API version 9, this API is supported in ArkTS widgets. NOTE This attribute is not applicable to SVG images.
sourceSize	{ width: number, height: number }	Decoding size of the image. This attribute can be used to reduce the image resolution when the image display size needs to be smaller than the component size. When used together with ImageFit.None, it can display a small image in the component. Unit: px Since API version 9, this API is supported in ArkTS widgets. NOTE This attribute works only when the target size is smaller than the source size. This attribute is not applicable to SVG images. This attribute is not applicable to PixelMap objects.
matchTextDirection	boolean	Whether to display the image in the system language direction. When this parameter is set to true, the image is horizontally flipped in the right-to-left (RTL) language context. Default value: false Since API version 9, this API is supported in ArkTS widgets.
fitOriginalSize	boolean	Whether to fit the component to the original size of the image source when the component size is not set. Default value: false Since API version 9, this API is supported in ArkTS widgets.
fillColor	ResourceColor	Fill color to be superimposed on the image. Since API version 9, this API is supported in ArkTS widgets. NOTE This attribute applies only to an SVG image. Once set, the fill color will replace that of the SVG image.
autoResize	boolean	Whether to resize the image source based on the size of the display area during image decoding. This resizing can help reduce the memory usage. For example, if the size of the original image is 1920 x 1080 and the size of the display area is 200 x 200, you can set this attribute to true so that the image is downsampled to 200 x 200. Default value: true Since API version 9, this API is supported in ArkTS widgets. NOTE As downsampling images results in some loss of information, it may reduce the image quality, causing issues such as aliasing. To retain the original image quality, set autoResize to false.
syncLoad8+	boolean	Whether to load the image synchronously. By default, the image is loaded asynchronously. During synchronous loading, the UI thread is blocked and the placeholder image is not displayed. Default value: false Since API version 9, this API is supported in ArkTS widgets. NOTE When loading a small image, you are advised to set syncLoad to true so that the image loading can be quickly completed on the main thread.
copyOption9+	CopyOptions	Whether the image can be copied. When copyOption is set to a value other than CopyOptions.None, the image can be copied in various manners, such as long pressing, right-clicking, or pressing Ctrl+C. Default value: CopyOptions.None Since API version 9, this API is supported in ArkTS widgets. NOTE SVG images cannot be copied.
colorFilter9+	ColorFilter	Color filter of the image. The input parameter is a 4 x 5 RGBA transformation matrix. The first row of the matrix represents a vector value of R (red), the second row represents a vector value of G (green), the third row represents a vector value of B (blue), and the fourth row represents a vector value of A (alpha). The four rows represent different RGBA vector values. The RGBA values are floating-point numbers between 0 and 1. When the diagonal value of the matrix is 1, the original color of the image is retained. Calculation rule: If the input filter matrix is as follows: Wherein the color is [R, G, B, A]. Then the color after filtering is [R’, G’, B’, A’]. Since API version 9, this API is supported in ArkTS widgets.
draggable	boolean	Whether the image is draggable. The value true means that the image is draggable, and false means the opposite. This attribute cannot be used together with the onDragStart event. Default value: false NOTE This API is supported since API version 9.

NOTE

• To use shortcut keys to copy the <Image> component, the component must be in focus. By default, the <Image> component is not focusable. To enable it to gain focus, set both the focusable and focusOnTouch attributes to true.
• For SVG images, only the following tags are included in the supported list: svg, rect, circle, ellipse, path, line, polyline, and polygon.

ImageInterpolation

Since API version 9, this API is supported in ArkTS widgets.

ImageRenderMode

Since API version 9, this API is supported in ArkTS widgets.

Events

In addition to the universal events, the following events are supported.

onComplete

onComplete(callback: (event?: { width: number, height: number, componentWidth: number, componentHeight: number, loadingStatus: number,contentWidth: number, contentHeight: number, contentOffsetX: number, contentOffsetY: number}) =&gt; void) }) =&gt; void)

Triggered when an image is successfully loaded or decoded. The size of the loaded image is returned.

Since API version 9, this API is supported in ArkTS widgets.

Parameters

onError

onError(callback: (event?: { componentWidth: number, componentHeight: number , message: string }) =&gt; void)

Triggered when an error occurs during image loading.

Since API version 9, this API is supported in ArkTS widgets.

Parameters

onFinish

onFinish(event: () =&gt; void)

Triggered when the animation playback in the loaded SVG image is complete. If the animation is an infinite loop, this callback is not triggered.

Only SVG images are supported.

Since API version 9, this API is supported in ArkTS widgets.

Example

Loading Images of Basic Types

@Entry
@Component
struct ImageExample1 {
  build() {
    Column() {
      Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Start }) {
        Row() {
          // Load a PNG image.
          Image($r('app.media.ic_camera_master_ai_leaf'))
            .width(110).height(110).margin(15)
            .overlay('png', { align: Alignment.Bottom, offset: { x: 0, y: 20 } })
          // Load a GIF image.
          Image($r('app.media.loading'))
            .width(110).height(110).margin(15)
            .overlay('gif', { align: Alignment.Bottom, offset: { x: 0, y: 20 } })
        }
        Row() {
          // Load an SVG image.
          Image($r('app.media.ic_camera_master_ai_clouded'))
            .width(110).height(110).margin(15)
            .overlay('svg', { align: Alignment.Bottom, offset: { x: 0, y: 20 } })
          // Load a JPG image.
          Image($r('app.media.ic_public_favor_filled'))
            .width(110).height(110).margin(15)
            .overlay('jpg', { align: Alignment.Bottom, offset: { x: 0, y: 20 } })
        }
      }
    }.height(320).width(360).padding({ right: 10, top: 10 })
  }
}

Loading Online Images

The default network timeout period is 5 minutes for loading online images. When using an online image, you are advised to use alt to configure the placeholder image displayed during loading. If more flexible network configuration is required, you can use the HTTP tool to send a network request, and then decode the returned data into a PixelMap object in the <Image> component. For details about image development, see Image Processing.

To use online images, the application must have the ohos.permission.INTERNET permission. For details about how to apply for a permission, see Declaring Permissions.

@Entry
@Component
struct ImageExample2 {
  build() {
    Column({ space: 10 }) {
      Image("https://www.example.com/xxx.png")// Enter an image URL.
        .alt($r('app.media.icon'))// Use alt to set a placeholder image displayed during image loading.
        .width(100)
        .height(100)
    }
  }
}

Adding Events to an Image

class tmp{
  width: number = 0
  height: number = 0
}
let msg:tmp = new tmp()
@Entry
@Component
struct ImageExample3 {
  @State widthValue: number = 0;
  @State heightValue: number = 0;
  private on: Resource = $r('app.media.image_on');
  private off: Resource = $r('app.media.image_off');
  private on2off: Resource = $r('app.media.image_on2off');
  private off2on: Resource = $r('app.media.image_off2on');
  @State src: Resource = this.on;

  build() {
    Column() {
      Row({ space: 20 }) {
        Column() {
          Image($r('app.media.img_example1'))
            .alt($r('app.media.ic_public_picture'))
            .sourceSize({
              width: 900,
              height: 900
            })
            .objectFit(ImageFit.Cover)
            .height(180).width(180)
            // Obtain the size of an image after the image loading is complete.
            .onComplete(msg => {
              if(msg){
                this.widthValue = msg.width
                this.heightValue = msg.height
              }
            })
            .onError(() => {
              console.log('load image fail')
            })
            .overlay('\nwidth: ' + String(this.widthValue) + ' height: ' + String(this.heightValue), {
              align: Alignment.Bottom,
              offset: { x: 0, y: 20 }
            })
        }
        // Add a click event so that a specific image is loaded upon clicking.
        Image(this.src)
          .width(120).height(120)
          .onClick(() => {
            if (this.src == this.on||this.src == this.off2on) {
              this.src = this.on2off
            } else {
              this.src = this.off2on
            }
          })
          .onFinish(() => {
            if (this.src == this.off2on) {
              this.src = this.on
            } else {
              this.src = this.off
            }
          })
      }
    }.width('100%')
  }
}

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