Interface (BackForwardList)

Defines the backforward list of the current WebView.

NOTE

• The initial APIs of this module are supported since API version 9. Updates will be marked with a superscript to indicate their earliest API version.

• The initial APIs of this interface are supported since API version 9.

• The sample effect is subject to the actual device.

Module to Import

import { webview } from '@kit.ArkWeb';

Attributes

System capability: SystemCapability.Web.Webview.Core

Name	Type	Read-Only	Optional	Description
currentIndex	number	No	No	Index of the current page in the backforward list.
size	number	No	No	Number of indexes in the backforward list. A maximum of 50 indexes can be stored. If this limit is exceeded, the start records will be overwritten.

getItemAtIndex

getItemAtIndex(index: number): HistoryItem

Obtains information about a history item with a specified index in the backforward list.

System capability: SystemCapability.Web.Webview.Core

Parameters

Name	Type	Mandatory	Description
index	number	Yes	Index of the history item in the backforward list.

Returns

Type	Description
HistoryItem	History item.

Error codes

For details about the error codes, see Universal Error Codes.

Error Code	Error Message
401	Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types. 3.Parameter verification failed.

Example

// xxx.ets
import { webview } from '@kit.ArkWeb';
import { BusinessError } from '@kit.BasicServicesKit';
import { image } from '@kit.ImageKit';

@Entry
@Component
struct WebComponent {
  controller: webview.WebviewController = new webview.WebviewController();
  @State icon: image.PixelMap | undefined = undefined;

  build() {
    Column() {
      Button('getBackForwardEntries')
        .onClick(() => {
          try {
            let list = this.controller.getBackForwardEntries();
            let historyItem = list.getItemAtIndex(list.currentIndex);
            console.info("HistoryItem: " + JSON.stringify(historyItem));
            this.icon = historyItem.icon;
          } catch (error) {
            console.error(`ErrorCode: ${(error as BusinessError).code},  Message: ${(error as BusinessError).message}`);
          }
        })
      Web({ src: 'www.example.com', controller: this.controller })
    }
  }
}