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使用 Azure 通信服务 UI 库请求相机和麦克风访问

重要

Azure 通信服务的这一功能目前以预览版提供。

预览版 API 和 SDK 在没有服务级别协议的情况下提供。 建议不要将它们用于生产工作负荷。 某些功能可能不受支持或者已受限。

有关详细信息，请参阅 Microsoft Azure 预览版补充使用条款。

本教程是“呼叫准备”三部分系列教程的续篇，承自上一篇：确保用户使用受支持的浏览器。

下载代码

在 GitHub 上访问本教程的完整代码。

请求访问相机和麦克风

对于呼叫应用程序，用户授予使用麦克风和相机的权限通常至关重要。 在本部分中，我们将创建一系列组件，用于支持用户授予对相机和麦克风的访问权限。 我们向用户显示提示，以指导他们授予访问权限。 如果未授予访问权限，我们会通过提示通知用户。

创建相机和麦克风访问提示

我们首先创建一系列设备权限提示，让用户进入他们已接受麦克风和相机权限的状态。 这些提示使用 UI 库中的 CameraAndMicrophoneSitePermissions 组件。 与“浏览器不受支持”提示一样，我们在 FluentUI modal 中托管这些提示。

src/DevicePermissionPrompts.tsx

import { CameraAndMicrophoneSitePermissions } from '@azure/communication-react';
import { Modal } from '@fluentui/react';

/** Modal dialog that prompt the user to accept the Browser's device permission request. */
export const AcceptDevicePermissionRequestPrompt = (props: { isOpen: boolean }): JSX.Element => (
  <PermissionsModal isOpen={props.isOpen} kind="request" />
);

/** Modal dialog that informs the user we are checking for device access. */
export const CheckingDeviceAccessPrompt = (props: { isOpen: boolean }): JSX.Element => (
  <PermissionsModal isOpen={props.isOpen} kind="check" />
)

/** Modal dialog that informs the user they denied permission to the camera or microphone with corrective steps. */
export const PermissionsDeniedPrompt = (props: { isOpen: boolean }): JSX.Element => (
  <PermissionsModal isOpen={props.isOpen} kind="denied" />
);

/** Base component utilized by the above prompts for better code separation. */
const PermissionsModal = (props: { isOpen: boolean, kind: "denied" | "request" | "check" }): JSX.Element => (
  <Modal isOpen={props.isOpen}>
    <CameraAndMicrophoneSitePermissions
      appName={'this site'}
      kind={props.kind}
      onTroubleshootingClick={() => alert('This callback should be used to take the user to further troubleshooting')}
    />
  </Modal>
);

检查相机和麦克风访问

在这里，我们添加了两个新的实用工具函数，用于检查和请求相机和麦克风访问。 创建一个名为 devicePermissionUtils.ts 的文件，其中包含 checkDevicePermissionsState 和 requestCameraAndMicrophonePermissions 这两个函数。 checkDevicePermissionsState 使用 PermissionAPI。 但是，Firefox 不支持查询相机和麦克风，因此我们要确保该方法会在这种情况下返回 unknown。 稍后，我们会确保在提示用户授予权限时处理 unknown 的情况。

src/DevicePermissionUtils.ts

import { DeviceAccess } from "@azure/communication-calling";
import { StatefulCallClient } from "@azure/communication-react";

/**
 * Check if the user needs to be prompted for camera and microphone permissions.
 *
 * @remarks
 * The Permissions API we are using is not supported in Firefox, Android WebView or Safari < 16.
 * In those cases this returns 'unknown'.
 */
export const checkDevicePermissionsState = async (): Promise<{camera: PermissionState, microphone: PermissionState} | 'unknown'> => {
  try {
    const [micPermissions, cameraPermissions] = await Promise.all([
      navigator.permissions.query({ name: "microphone" as PermissionName }),
      navigator.permissions.query({ name: "camera" as PermissionName })
    ]);
    console.info('PermissionAPI results', [micPermissions, cameraPermissions]); // view console logs in the browser to see what the PermissionsAPI info is returned
    return { camera: cameraPermissions.state, microphone: micPermissions.state };
  } catch (e) {
    console.warn("Permissions API unsupported", e);
    return 'unknown';
  }
}

/** Use the DeviceManager to request for permissions to access the camera and microphone. */
export const requestCameraAndMicrophonePermissions = async (callClient: StatefulCallClient): Promise<DeviceAccess> => {
  const response = await (await callClient.getDeviceManager()).askDevicePermission({ audio: true, video: true });
  console.info('AskDevicePermission response', response); // view console logs in the browser to see what device access info is returned
  return response
}

提示用户授予对相机和麦克风的访问权限

现在，我们有了提示、检查和请求逻辑，我们将创建一个 DeviceAccessComponent 来向用户提示设备权限相关信息。 在此组件中，我们根据设备权限状态向用户显示不同的提示：

• 如果设备权限状态未知，我们会向用户显示一条提示，告知他们我们正在检查设备权限。
• 如果我们要请求权限，则会向用户显示一条提示，鼓励他们接受权限请求。
• 如果权限被拒绝，我们将向用户显示一条提示，告知用户他们已拒绝权限，需要授予权限才能继续。

src/DeviceAccessChecksComponent.tsx

import { useEffect, useState } from 'react';
import { CheckingDeviceAccessPrompt, PermissionsDeniedPrompt, AcceptDevicePermissionRequestPrompt } from './DevicePermissionPrompts';
import { useCallClient } from '@azure/communication-react';
import { checkDevicePermissionsState, requestCameraAndMicrophonePermissions } from './DevicePermissionUtils';

export type DevicesAccessChecksState = 'runningDeviceAccessChecks' |
  'checkingDeviceAccess' |
  'promptingForDeviceAccess' |
  'deniedDeviceAccess';

/**
 * This component is a demo of how to use the StatefulCallClient with CallReadiness Components to get a user
 * ready to join a call.
 * This component checks the browser support and if camera and microphone permissions have been granted.
 */
export const DeviceAccessChecksComponent = (props: {
  /**
   * Callback triggered when the tests are complete and successful
   */
  onTestsSuccessful: () => void
}): JSX.Element => {
  const [currentCheckState, setCurrentCheckState] = useState<DevicesAccessChecksState>('runningDeviceAccessChecks');
  

  // Run call readiness checks when component mounts
  const callClient = useCallClient();
  useEffect(() => {
    const runDeviceAccessChecks = async (): Promise<void> => {

      // First we check if we need to prompt the user for camera and microphone permissions.
      // The prompt check only works if the browser supports the PermissionAPI for querying camera and microphone.
      // In the event that is not supported, we show a more generic prompt to the user.
      const devicePermissionState = await checkDevicePermissionsState();
      if (devicePermissionState === 'unknown') {
        // We don't know if we need to request camera and microphone permissions, so we'll show a generic prompt.
        setCurrentCheckState('checkingDeviceAccess');
      } else if (devicePermissionState.camera === 'prompt' || devicePermissionState.microphone === 'prompt') {
        // We know we need to request camera and microphone permissions, so we'll show the prompt.
        setCurrentCheckState('promptingForDeviceAccess');
      }

      // Now the user has an appropriate prompt, we can request camera and microphone permissions.
      const devicePermissionsState = await requestCameraAndMicrophonePermissions(callClient);

      if (!devicePermissionsState.audio || !devicePermissionsState.video) {
        // If the user denied camera and microphone permissions, we prompt the user to take corrective action.
        setCurrentCheckState('deniedDeviceAccess');
      } else {
        // Test finished successfully, trigger callback to parent component to take user to the next stage of the app.
        props.onTestsSuccessful();
      }
    };

    runDeviceAccessChecks();
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  return (
    <>
      {/* We show this when we are prompting the user to accept device permissions */}
      <AcceptDevicePermissionRequestPrompt isOpen={currentCheckState === 'promptingForDeviceAccess'} />

      {/* We show this when the PermissionsAPI is not supported and we are checking what permissions the user has granted or denied */}
      <CheckingDeviceAccessPrompt isOpen={currentCheckState === 'checkingDeviceAccess'} />

      {/* We show this when the user has failed to grant camera and microphone access */}
      <PermissionsDeniedPrompt isOpen={currentCheckState === 'deniedDeviceAccess'} />
    </>
  );
}

创建完此组件后，将其添加到 App.tsx。 首先添加 import 语句：

import { DeviceAccessChecksComponent } from './DeviceAccessChecksComponent';

然后将类型 TestingState 更新为以下值：

type TestingState = 'runningEnvironmentChecks' | 'runningDeviceAccessChecks' | 'finished';

最后，更新 App 组件：

/**
 * Entry point of a React app.
 *
 * This shows a PreparingYourSession component while the CallReadinessChecks are running.
 * Once the CallReadinessChecks are finished, the TestComplete component is shown.
 */
const App = (): JSX.Element => {
  const [testState, setTestState] = useState<TestingState>('runningEnvironmentChecks');

  return (
    <FluentThemeProvider>
      <CallClientProvider callClient={callClient}>
        {/* Show a Preparing your session screen while running the environment checks */}
        {testState === 'runningEnvironmentChecks' && (
          <>
            <PreparingYourSession />
            <EnvironmentChecksComponent onTestsSuccessful={() => setTestState('runningDeviceAccessChecks')} />
          </>
        )}
        
        {/* Show a Preparing your session screen while running the device access checks */}
        {testState === 'runningDeviceAccessChecks' && (
          <>
            <PreparingYourSession />
            <DeviceAccessChecksComponent onTestsSuccessful={() => setTestState('finished')} />
          </>
        )}


        {/* After the device setup is complete, take the user to the call. For this sample we show a test complete page. */}
        {testState === 'finished' && <TestComplete />}
      </CallClientProvider>
    </FluentThemeProvider>
  );
}

应用向用户显示提示，引导他们完成设备访问：

注意

对于测试，我们建议在 InPrivate/Incognito 模式下访问应用，在这之前就不需要为 localhost:3000 授予相机和麦克风权限。

后续步骤

第 3 部分：为呼叫选择麦克风和摄像头