元服务通过router事件刷新卡片内容

问题现象

元服务卡片与卡片提供方如何交互，如元服务卡片跳转元服务页面，并刷新卡片内容？

背景知识

ArkTS卡片提供页面交互能力，包括卡片与卡片提供方的页面跳转、卡片拉起卡片提供方进程、卡片与卡片提供方的消息传递。

解决方案

可以使用router事件跳转到指定UIAbility，以完成点击卡片跳转至元服务页面，并刷新卡片内容，详细步骤及示例代码如下：

1. 创建元服务项目，并完成新建元服务卡片。
2. 删除“WidgetCard.ets”文件中默认生成的卡片代码，新增如下示例代码，通过调用postCardAction接口，触发router事件拉起EntryAbility至前台：

   let storageUpdateRouter = new LocalStorage();
   
   @Entry(storageUpdateRouter)
   @Component
   struct WidgetCard {
     /*
      * The title.
      */
     @LocalStorageProp('title') title: ResourceStr = 'original title';
     /*
      * The action type.
      */
     readonly actionType: string = 'router';
     /*
      * The ability name.
      */
     readonly abilityName: string = 'EntryAbility';
     /*
      * The message.
      */
     readonly message: string = 'update title';
   
     build() {
       Row() {
         Column() {
           Text(this.title)
             .fontSize(14)
             .fontWeight(FontWeight.Medium)
             .fontColor($r('sys.color.font'));
         }
         .width('100%');
       }
       .height('100%')
       .backgroundColor($r('sys.color.comp_background_primary'))
       .onClick(() => {
         postCardAction(this, {
           action: this.actionType,
           abilityName: this.abilityName,
           params: {
             message: this.message
           }
         });
       });
     }
   }

3. 在EntryAbility的onCreate或者onNewWant生命周期中可以通过入参want获取卡片的formID和传递过来的参数信息，然后调用updateForm接口刷新卡片。

   import { AbilityConstant, UIAbility, Want } from '@kit.AbilityKit';
   import { hilog } from '@kit.PerformanceAnalysisKit';
   import { window } from '@kit.ArkUI';
   import { formBindingData, formInfo, formProvider } from '@kit.FormKit';
   
   const DOMAIN = 0x0000;
   const TAG = 'testTag';
   
   export default class EntryAbility extends UIAbility {
     onCreate(want: Want, launchParam: AbilityConstant.LaunchParam): void {
       hilog.info(DOMAIN, TAG, 'onCreate Want:', want.action, launchParam.launchReason);
       this.handleFormRouterEvent(want, 'onCreate');
     }
   
     handleFormRouterEvent(want: Want, source: string): void {
       hilog.info(DOMAIN, TAG, `handleFormRouterEvent ${source}`);
       if (want.parameters && want.parameters[formInfo.FormParam.IDENTITY_KEY] !== undefined) {
         let curFormId = want.parameters[formInfo.FormParam.IDENTITY_KEY].toString();
         let formData: Record<string, string> = {
           'title': 'updated title ' + Date.now()
         };
         let formMsg = formBindingData.createFormBindingData(formData);
         formProvider.updateForm(curFormId, formMsg).then((data) => {
           hilog.info(DOMAIN, TAG, 'updateForm success.', JSON.stringify(data));
         }).catch((error: BusinessError) => {
           hilog.info(DOMAIN, TAG, 'updateForm failed.', JSON.stringify(error));
         });
       }
     }
   
     onNewWant(want: Want, launchParam: AbilityConstant.LaunchParam): void {
       hilog.info(DOMAIN, TAG, 'onNewWant Want:', want.action, launchParam.launchReason);
       this.handleFormRouterEvent(want, 'onNewWant');
     }
   
     onDestroy(): void {
       hilog.info(DOMAIN, TAG, '%{public}s', 'Ability onDestroy');
     }
   
     onWindowStageCreate(windowStage: window.WindowStage): void {
       // Main window is created, set main page for this ability
       hilog.info(DOMAIN, TAG, '%{public}s', 'Ability onWindowStageCreate');
   
       windowStage.loadContent('pages/Index', (err) => {
         if (err.code) {
           hilog.error(DOMAIN, TAG, 'Failed to load the content. Cause: %{public}s', JSON.stringify(err));
           return;
         }
         hilog.info(DOMAIN, TAG, 'Succeeded in loading the content.');
       });
     }
   
     onWindowStageDestroy(): void {
       // Main window is destroyed, release UI related resources
       hilog.info(DOMAIN, TAG, '%{public}s', 'Ability onWindowStageDestroy');
     }
   
     onForeground(): void {
       // Ability has brought to foreground
       hilog.info(DOMAIN, TAG, '%{public}s', 'Ability onForeground');
     }
   
     onBackground(): void {
       // Ability has back to background
       hilog.info(DOMAIN, TAG, '%{public}s', 'Ability onBackground');
     }
   };

常见FAQ

Q：元服务卡片不能自动刷新。

A：服务卡片默认是关闭自动刷新的，需要updateEnabled设置成true手动打开。