UIAbility组件间的交互

一、Want

是UIAbility组件间交互载体。

Want启动UIAbility组件的两种方式：

1、显示Want启动

启动某个明确UIAbility组件时使用；需要在Want参数中设置启动的应用包名和UIAbility组件名。

2、隐式Want启动

需要使用某个应用的能力，不关心提供能力的具体应用时使用；不在Want参数中设置启动的UIAbility组件名；需要在Want中设置UIAbility组件的匹配条件；系统根据匹配条件提供命中应用供用户选择。

二、显示Want启动UIAbility组件开发

1、调用方页面

let context = getContext(this) as common.UIAbilityContext;
let wantInfo: Want = {deviceId: '', // deviceId为空表示本设备bundleName: 'com.samples.stagemodelabilitydevelop',moduleName: 'entry', // moduleName非必选abilityName: 'FuncAbilityA',parameters: {// 自定义信息info: '来自EntryAbility Page_UIAbilityComponentsInteractive页面'},
};
// context为调用方UIAbility的UIAbilityContext
context.startAbility(wantInfo).then(() => {hilog.info(DOMAIN_NUMBER, TAG, 'startAbility success.');
}).catch((error: BusinessError) => {hilog.error(DOMAIN_NUMBER, TAG, 'startAbility failed.');
});

2、被调用方UIAbility文件

import { AbilityConstant, UIAbility, Want } from '@kit.AbilityKit';export default class FuncAbilityA extends UIAbility {onCreate(want: Want, launchParam: AbilityConstant.LaunchParam): void {// 接收调用方UIAbility传过来的参数let funcAbilityWant = want;let info = funcAbilityWant?.parameters?.info;}//...
}

注意：

在被拉起的FuncAbility中，可以通过获取传递过来的want参数的parameters来获取拉起方UIAbility的PID、Bundle Name等信息。

被调用UIAbility冷启动时通过onCreate()函数接收Want，热启动时通过onNewWant()函数接收Want。

三、隐式Want启动UIAbility组件开发---启动浏览器

1、设置被调用方的module.json5配置文件

{"module":{"abilities":[{"skills":[{// 设置UIAbility支持的能力类型，如浏览器类型"entities":["entity.system.browsable"],// 设置UIAbility支持的操作，如查看数据"actions":["ohos.want.action.viewData"]}]}
}

2、调用方页面

let context:common.UIAbilityContext = getContext(this) as common.UIAbilityContext;
let wantInfo: Want = {action: 'ohos.want.action.viewData',entities: ['entity.system.browsable'],url:'https://www.huawei.com/cn/, 
};
// context为调用方UIAbility的UIAbilityContext
context.startAbility(wantInfo).then(() => {// 启动成功
}).catch((error: BusinessError) => {// 启动失败
});

四、UIAbility启动

一个UIAbility可以对应多个页面，在不同的场景下启动该UIAbility时需要展示不同的页面，例如从一个UIAbility的页面中跳转到另外一个UIAbility时，希望启动目标UIAbility的指定页面。

UIAbility的启动分为两种情况：UIAbility冷启动和UIAbility热启动。

1、冷启动

指的是UIAbility实例处于完全关闭状态下被启动，这需要完整地加载和初始化UIAbility实例的代码、资源等。

目标UIAbility冷启动时，在目标UIAbility的onCreate()生命周期回调中，接收调用方传过来的参数。然后在目标UIAbility的onWindowStageCreate()生命周期回调中，解析EntryAbility传递过来的want参数，获取到需要加载的页面信息url，传入windowStage.loadContent()方法。

import { AbilityConstant, Want, UIAbility } from '@kit.AbilityKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
import { window, UIContext } from '@kit.ArkUI';const DOMAIN_NUMBER: number = 0xFF00;
const TAG: string = '[EntryAbility]';export default class EntryAbility extends UIAbility {funcAbilityWant: Want | undefined = undefined;uiContext: UIContext | undefined = undefined;onCreate(want: Want, launchParam: AbilityConstant.LaunchParam): void {// 接收调用方UIAbility传过来的参数this.funcAbilityWant = want;}onWindowStageCreate(windowStage: window.WindowStage): void {// Main window is created, set main page for this abilityhilog.info(DOMAIN_NUMBER, TAG, '%{public}s', 'Ability onWindowStageCreate');// Main window is created, set main page for this abilitylet url = 'pages/Index';if (this.funcAbilityWant?.parameters?.router && this.funcAbilityWant.parameters.router === 'funcA') {url = 'pages/Page_ColdStartUp';}windowStage.loadContent(url, (err, data) => {// ...});}
}

2、热启动

指的是UIAbility实例已经启动并在前台运行过，由于某些原因切换到后台，再次启动该UIAbility实例，这种情况下可以快速恢复UIAbility实例的状态。

在应用开发中，会遇到目标UIAbility实例之前已经启动过的场景，这时再次启动目标UIAbility时，不会重新走初始化逻辑，只会直接触发onNewWant()生命周期方法。为了实现跳转到指定页面，需要在onNewWant()中解析参数进行处理。

热启动举例：

import { hilog } from '@kit.PerformanceAnalysisKit';
import { Want, UIAbility } from '@kit.AbilityKit';
import { window, UIContext } from '@kit.ArkUI';const DOMAIN_NUMBER: number = 0xFF00;
const TAG: string = '[EntryAbility]';export default class EntryAbility extends UIAbility {funcAbilityWant: Want | undefined = undefined;uiContext: UIContext | undefined = undefined;// ...onWindowStageCreate(windowStage: window.WindowStage): void {// Main window is created, set main page for this abilityhilog.info(DOMAIN_NUMBER, TAG, '%{public}s', 'Ability onWindowStageCreate');let url = 'pages/Index';if (this.funcAbilityWant?.parameters?.router && this.funcAbilityWant.parameters.router === 'funcA') {url = 'pages/Page_ColdStartUp';}windowStage.loadContent(url, (err, data) => {if (err.code) {return;}let windowClass: window.Window;windowStage.getMainWindow((err, data) => {if (err.code) {hilog.error(DOMAIN_NUMBER, TAG, `Failed to obtain the main window. Code is ${err.code}, message is ${err.message}`);return;}windowClass = data;this.uiContext = windowClass.getUIContext();});hilog.info(DOMAIN_NUMBER, TAG, 'Succeeded in loading the content. Data: %{public}s', JSON.stringify(data) ?? '');});}
}

import { AbilityConstant, Want, UIAbility } from '@kit.AbilityKit';
import { hilog } from '@kit.PerformanceAnalysisKit';
import type { Router, UIContext } from '@kit.ArkUI';
import type { BusinessError } from '@kit.BasicServicesKit';const DOMAIN_NUMBER: number = 0xFF00;
const TAG: string = '[EntryAbility]';export default class EntryAbility extends UIAbility {funcAbilityWant: Want | undefined = undefined;uiContext: UIContext | undefined = undefined;// ...onNewWant(want: Want, launchParam: AbilityConstant.LaunchParam): void {if (want?.parameters?.router && want.parameters.router === 'funcA') {let funcAUrl = 'pages/Page_HotStartUp';if (this.uiContext) {let router: Router = this.uiContext.getRouter();router.pushUrl({url: funcAUrl}).catch((err: BusinessError) => {hilog.error(DOMAIN_NUMBER, TAG, `Failed to push url. Code is ${err.code}, message is ${err.message}`);});}}}
}