24087de4创建于 2024年11月18日历史提交

Holding a Video Conference with WebRTC

The Web component can start a camera and microphone by calling the W3C Standards-compliant API navigator.mediaDevices.getUserMedia() in JavaScript, and receive the permission request notification through onPermissionRequest. To call these APIs, you need to declare the audio permissions in the module.json5 file.

  • For details about how to add audio permissions, see Declaring Permissions.

    "requestPermissions":[
       {
         "name" : "ohos.permission.CAMERA"
       },
       {
         "name" : "ohos.permission.MICROPHONE"
       }
     ]
    

The constraints parameter in the API is a MediaStreamConstraints object that specifies the types of media to request. It contains two members: video and audio.

In the following example, when a user clicks the button for enabling the camera on the frontend page and the onConfirm button, the Web component starts the camera and microphone.

  • Application code:

    // xxx.ets
    import { webview } from '@kit.ArkWeb';
    import { BusinessError } from '@kit.BasicServicesKit';
    import { abilityAccessCtrl } from '@kit.AbilityKit';
    
    @Entry
    @Component
    struct WebComponent {
      controller: webview.WebviewController = new webview.WebviewController()
    
      aboutToAppear() {
        // Enable web frontend page debugging.
        webview.WebviewController.setWebDebuggingAccess(true);
        let atManager = abilityAccessCtrl.createAtManager();
        atManager.requestPermissionsFromUser(getContext(this), ['ohos.permission.CAMERA', 'ohos.permission.MICROPHONE'])
          .then((data) => {
            console.info('data:' + JSON.stringify(data));
            console.info('data permissions:' + data.permissions);
            console.info('data authResults:' + data.authResults);
          }).catch((error: BusinessError) => {
          console.error(`Failed to request permissions from user. Code is ${error.code}, message is ${error.message}`);
        })
      }
    
      aboutToAppear() {
        // Obtain the permission request notification. After the onConfirm button is clicked, the camera and microphone are started.
        webview.WebviewController.setWebDebuggingAccess(true);
        let atManager = abilityAccessCtrl.createAtManager();
        atManager.requestPermissionsFromUser(getContext(this), ['ohos.permission.CAMERA', 'ohos.permission.MICROPHONE'])
          .then(data => {
            let result: Array<number> = data.authResults;
            let hasPermissions1 = true;
            result.forEach(item => {
              if (item === -1) {
                hasPermissions1 = false;
              }
            })
            if (hasPermissions1) {
              console.info("hasPermissions1");
            } else {
              console.info(" not hasPermissions1");
            }
          }).catch(() => {
          return;
        });
      }
    
      build() {
        Column() {
          Web({ src: $rawfile('index.html'), controller: this.controller })
            .onPermissionRequest((event) => {
              if (event) {
                AlertDialog.show({
                  title: 'title',
                  message: 'text',
                  primaryButton: {
                    value: 'deny',
                    action: () => {
                      event.request.deny();
                    }
                  },
                  secondaryButton: {
                    value: 'onConfirm',
                    action: () => {
                      event.request.grant(event.request.getAccessibleResource());
                    }
                  },
                  cancel: () => {
                    event.request.deny();
                  }
                })
              }
            })
        }
      }
    }
    
  • Code of the index.html page:

    <!-- index.html -->
    <!DOCTYPE html>
    <html>
    <head>
      <meta charset="UTF-8">
    </head>
    <body>
    <video id="video" width="500px" height="500px" autoplay="autoplay"></video>
    <canvas id="canvas" width="500px" height="500px"></canvas>
    <br>
    <input type="button" title="HTML5 Camera" value="Enable Camera" onclick="getMedia()"/>
    <script>
      function getMedia()
      {
        let constraints = {
          video: {width: 500, height: 500},
          audio: true
        };
        // Obtain the video camera area.
        let video = document.getElementById("video");
        // Returned Promise object
        let promise = navigator.mediaDevices.getUserMedia(constraints);
        // then() is asynchronous. Invoke the MediaStream object as a parameter.
        promise.then(function (MediaStream) {
          video.srcObject = MediaStream;
          video.play();
        });
      }
    </script>
    </body>
    </html>