Widget Event Capability Overview

The ArkTS widget provides the postCardAction() API for interaction between the widget internal and the provider application. Currently, this API supports the router, message, and call events and can be called only in the widget.

WidgetPostCardAction

Definition: postCardAction(component: Object, action: Object): void

Parameters:

Name Type Mandatory Description
component Object Yes Instance of the current custom component. Generally, this is transferred.
action Object Yes Action description. For details, see the following table.

Description of the action parameter

Key Value Description
"action" string Action type.
- "router": application redirection. If this type of action is triggered, the corresponding UIAbility is displayed. Only the UIAbility of the current application can be displayed.
- "message": custom message. If this type of action is triggered, the onFormEvent() lifecycle callback of the provider FormExtensionAbility is called.
- "call": application startup in the background. If this type of action is triggered, the corresponding UIAbility is started but does not run in the foreground. The target application must have the permission to run in the background (ohos.permission.KEEP_BACKGROUND_RUNNING).
"bundleName" string Name of the target bundle when action is "router" or "call". This parameter is optional.
"moduleName" string Name of the target module when action is "router" or "call". This parameter is optional.
"abilityName" string Name of the target UIAbility when action is "router" or "call". This parameter is mandatory.
"params" Object Additional parameters carried in the current action. The value is a key-value pair in JSON format.

Sample code of the postCardAction() API:

Button ('Jump')
  .width('40%')
  .height('20%')
  .onClick(() => {
    postCardAction(this, {
      'action': 'router',
      'bundleName': 'com.example.myapplication',
      'abilityName': 'EntryAbility',
      'params': {
        'message': 'testForRouter' // Customize the message to be sent.
      }
    });
  })

The following are typical widget development scenarios that can be implemented through widget events: