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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源码参考：[资源API调用示例]

cpp 复制代码

/*

 * 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

@Component

struct 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]

cpp 复制代码

/*

 * 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

@Component

struct 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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