OpenHarmony实例：【资源管理器】

介绍

本工程使用[@ohos.app.ability.common] 接口中的AbilityContext类，获取资源管理器resourceManager，使用[@ohos.resourceManager.d.ts]中的接口，展示了格式化字符串查询、基于指定屏幕分辨率查询媒体资源、获取系统资源管理对象等基础功能，以及展示了资源静态overlay以及运行时overlay的特性功能。

效果预览

主页

使用说明

此界面为主页面，其中展示了资源管理API各类接口的调用以及特性Overlay场景功能。其作用有：

1、点击资源API调用示例按钮，可跳转到资源API示例页面

2、点击Overlay使用示例，可以跳转到Overlay的使用示例界面。

资源API调用示例

资源API测试

使用说明

此页面展示了当前资源管理接口的调用以及接口对应的返回结果。

静态overlay场景

overlay场景

使用说明

此页面展示静态overlay功能，功能使用如下：

1、静态overlay是默认使能的，当前显示的是静态overlay中的字符串和图标。

2、点击Disable可以触发去使能，重启应用可以恢复显示应用的字符串和图标。

3、点击enable可以触发使能，重启应用可以再次显示overlay中的字符串和图标。

源码参考：[Overlay示例]在最后

运行时overlay场景

运行时overlay场景

使用说明

此页面展示运行时overlay功能，功能使用如下：

1、点击addResource可以触发运行时overlay，此时会使用运行时overlay中的资源覆盖之前的字符串和图标。

2、点击removeResource可以触发移除运行时overlay，此时会移除运行时overlay，恢复到覆盖前的字符串和图标。

具体实现

资源API调用示例具体实现：

1、使用getContext()接口获取context对象，使用context.resourceManager获取资源管理对象，然后调用resourceManager内部的相关接口获取对应资源，例如：

获取字符串资源：resourceManager.getStringValue()
获取字符串数组资源：resourceManager.getStringArrayValue()
获取图片资源：resourceManager.getMediaContent()
获取格式化字符串资源：resourceManager.getStringSync()
获取指定屏幕分辨率媒体资源：resourceManager.getMediaContentBase64()

2、导包resourceManager，使用resourceManager.getSystemResourceManager()获取系统资源管理对象，然后获取系统资源。

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搜狗高速浏览器截图20240326151450.png

源码参考：[资源API调用示例]

/** Copyright (c) 2023 Huawei Device Co., Ltd.* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/import resourceManager from '@ohos.resourceManager';import hilog from '@ohos.hilog';import { BusinessError } from '@ohos.base';const TAG = '[Sample_ResourceManager]';const DOMAIN = 0xFF00;const SPECIFIED_NUM = 2;let resMgr = getContext().resourceManager;async function getString(resId: number): Promise<string | undefined> {try {let value = await resMgr.getStringValue(resId);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getStringValue failed, error code: ${code}, message: ${message}.`);return;}}async function getStringArray(resource: resourceManager.Resource): Promise<Array<string> | undefined> {try {let value = await resMgr.getStringArrayValue(resource);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getStringArrayValue failed, error code: ${code}, message: ${message}.`);return;}}async function getPluralString(resId: number, num: number): Promise<string | undefined> {try {let value = await resMgr.getPluralStringValue(resId, num);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getPluralStringValue failed, error code: ${code}, message: ${message}.`);return;}}async function getDeviceCapability(): Promise<resourceManager.DeviceCapability | undefined> {try {let value = await resMgr.getDeviceCapability();return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getDeviceCapability failed, error code: ${code}, message: ${message}.`);return;}}async function getConfiguration(): Promise<resourceManager.Configuration | undefined> {try {let value = await resMgr.getConfiguration();return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getConfiguration failed, error code: ${code}, message: ${message}.`);return;}}async function getMedia(resId: number): Promise<Uint8Array | undefined> {try {let value = await resMgr.getMediaContent(resId);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getMediaContent failed, error code: ${code}, message: ${message}.`);return;}}async function getMediaBase64(resId: number): Promise<string | undefined> {try {let value = await resMgr.getMediaContentBase64(resId);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getMediaContentBase64 failed, error code: ${code}, message: ${message}.`);return;}}function getFormatString(resId: number, world: string): string | undefined {try {let value = resMgr.getStringSync(resId, world);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getStringSync failed, error code: ${code}, message: ${message}.`);return;}}async function getDensityMediaBase64(resId: number, density: number): Promise<string | undefined> {try {let value = await resMgr.getMediaContentBase64(resId, density);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getDensityMediaBase64 failed, error code: ${code}, message: ${message}.`);return;}}async function getSystemMediaBase64(resId: number): Promise<string | undefined> {// 获取仅系统资源管理对象let sysMgr = resourceManager.getSystemResourceManager();try {let value = await sysMgr.getMediaContentBase64(resId);return value;} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;hilog.error(DOMAIN, TAG, `getMediaContentBase64 failed, error code: ${code}, message: ${message}.`);return;}}@Entry@Componentstruct Index {@State string_str: string = 'string'@State strArray: string = 'stringArray'@State plural: string = 'plural'@State configuration: string = 'configuration'@State capability: string = 'capability'@State media: string = 'media'@State mediaBase: string = 'mediaBase'@State formatStr: string = 'Format String'@State densityMedia: string = 'Density Media'@State systemRes: string = 'System Res'async aboutToAppear() {this.string_str = await getString($r('app.string.string_str').id) as string;let resource: resourceManager.Resource = {bundleName: "ohos.samples.resourcemanager",moduleName: "entry",id: $r('app.strarray.str_array').id}this.strArray = JSON.stringify(await getStringArray(resource) as Array<string>);this.plural = await getPluralString($r('app.plural.eat_apple').id, SPECIFIED_NUM) as string;this.configuration = JSON.stringify(await getConfiguration() as resourceManager.Configuration);this.capability = JSON.stringify(await getDeviceCapability() as resourceManager.DeviceCapability);this.media = JSON.stringify(((await getMedia($r('app.media.app_icon').id)) as Uint8Array).length);this.mediaBase = JSON.stringify(((await getMediaBase64($r('app.media.app_icon').id)) as string).length);this.formatStr = getFormatString($r('app.string.formatStr').id,await getString($r('app.string.world').id) as string) as string;this.densityMedia = await getDensityMediaBase64($r('app.media.density').id, 640) as string;this.systemRes = await getSystemMediaBase64($r('sys.media.ohos_app_icon').id) as string;}build() {Column() {Text($r('app.string.title')).width('100%').height(50).backgroundColor($r('app.color.text_color')).fontColor(Color.White).fontSize(20).padding({ left: 15 })Scroll() {Column() {Text($r('app.string.stringDesc')).fontSize(25)Text(this.string_str).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.stringArrayDesc')).fontSize(25)Text(this.strArray).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.pluralStringDesc')).fontSize(25)Text(this.plural).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.configurationDesc')).fontSize(25)Text(this.configuration).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.capabilityDesc')).fontSize(25)Text(this.capability).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.mediaDesc')).fontSize(25)Text(this.media).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.mediaBase64Desc')).fontSize(25)Text(this.mediaBase).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.formatStrDesc')).fontSize(25)Text(this.formatStr).fontSize(25).fontColor('#ffff0000').fontWeight(FontWeight.Bold)Text($r('app.string.densityMediaDesc')).fontSize(25)Image(this.densityMedia).id('getDensityMedia').height('10%')Text($r('app.string.systemResDesc')).fontSize(25)Image(this.systemRes).id('getSystemMedia').height('10%')}.width('100%').padding(10).alignItems(HorizontalAlign.Start)}}.width('100%').height('100%')}}

overlay场景的具体实现：

1、静态overlay主要是通过加载overly中的资源实现资源覆盖，需要在对应的module.json中添加"targetModuleName":"entry"，表示覆盖entry中的资源，默认使能，也可调用包管理接口进行使能和去使能。

使用步骤为：在安装完entry的hap后，需要把library模块生成的library-default-signed.hsp推送到/data/test下，使用bm install命令进行安装。

脚本语言如下：

hdc_std shell mount -o remount,rw /

hdc_std install ./entry-default-signed.hap

hdc_std shell mkdir /data/test

hdc_std file send ./libraryOverlay-default-signed.hsp /data/test

hdc_std shell bm install -p "/data/test/libraryOverlay-default-signed.hsp"

pause

2、运行时overlay资源加载，主要是在应用运行过程中实现资源的覆盖，需要应用主动调用资源的addResource接口实现资源的覆盖以及资源的移除，此功能不持久化。

使用步骤为: 在安装完entry的hap后，需要把libraryRuntimeOverlay模块生成的libraryRuntimeOverlay-default-signed.hsp推送到应用对应的安装目录下。

脚本语言如下：

hdc_std shell mount -o remount,rw /

hdc_std install ./entry-default-signed.hap

hdc_std file send ./libraryRuntimeOverlay-default-signed.hsp /data/app/el1/bundle/public/ohos.samples.resourcemanager

pause

源码参考：[Overlay示例]

/** Copyright (c) 2023 Huawei Device Co., Ltd.* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/import overlay from '@ohos.bundle.overlay';import { BusinessError } from '@ohos.base';@Entry@Componentstruct Overlay {private resmgr = getContext().resourceManager;@State message: string = 'Test Overlay'@State resources: string = this.resmgr.getStringSync($r("app.string.test_string").id)@State pixmap: PixelMap = this.resmgr.getDrawableDescriptor($r("app.media.icon").id).getPixelMap()build() {Column() {Text($r('app.string.title')).width('100%').height(50).backgroundColor($r('app.color.text_color')).fontColor(Color.White).fontSize(20).padding({ left: 15 })Text(`${this.message}`).fontSize(50).fontWeight(FontWeight.Bold).margin({top: 40})Button() {Text('disable').fontSize(20).fontWeight(FontWeight.Bold)}.type(ButtonType.Capsule).margin({top: 50}).backgroundColor('#0D9FFB').width('50%').height('5%').onClick(() => {// 非使能overlay.setOverlayEnabled("libraryOverlay", false, (err, data) => {if (err && err.code != 0) {console.log("error:" + JSON.stringify(err));this.message = this.resmgr.getStringSync($r('app.string.unEnableFailed').id);} else {console.log("data:" + JSON.stringify(data));this.message = this.resmgr.getStringSync($r('app.string.unEnableSuccess').id);}})})Button() {Text('enable').fontSize(20).fontWeight(FontWeight.Bold)}.type(ButtonType.Capsule).margin({top: 20}).backgroundColor('#0D9FFB').width('50%').height('5%').onClick(() => {// 使能overlay.setOverlayEnabled("libraryOverlay", true, (err, data) => {if (err && err.code != 0) {console.log("error:" + JSON.stringify(err));this.message = this.resmgr.getStringSync($r('app.string.enableFailed').id);} else {this.message = this.resmgr.getStringSync($r('app.string.enableSuccess').id);}})})Button() {Text('addResource').fontSize(20).fontWeight(FontWeight.Bold)}.type(ButtonType.Capsule).margin({top: 20}).backgroundColor('#0D9FFB').width('50%').height('5%').onClick(() => {let path = getContext().bundleCodeDir + "/libraryRuntimeOverlay-default-signed.hsp";try {let ret = this.resmgr.addResource(path);console.error("addResource: ret" + JSON.stringify(ret));} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;console.error(`addResource failed, error code: ${code}, message: ${message}.`);}this.pixmap = this.resmgr.getDrawableDescriptor($r("app.media.icon").id).getPixelMap();this.resources = this.resmgr.getStringSync($r("app.string.test_string").id);})Button() {Text('removeResource').fontSize(20).fontWeight(FontWeight.Bold)}.type(ButtonType.Capsule).margin({top: 20}).backgroundColor('#0D9FFB').width('50%').height('5%').onClick(() => {let path = getContext().bundleCodeDir + "/libraryRuntimeOverlay-default-signed.hsp";try {this.resmgr.removeResource(path);} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;console.error(`removeResource failed, error code: ${code}, message: ${message}.`);}this.pixmap = this.resmgr.getDrawableDescriptor($r("app.media.icon").id).getPixelMap();this.resources = this.resmgr.getStringSync($r("app.string.test_string").id);})Image(this.pixmap).width(100).height(100)Text(this.resources).fontSize(50).fontWeight(FontWeight.Bold)}.width('100%').height('100%')}}

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