准备工作

声明权限:

    <uses-permission android:name="android.permission.CAMERA" />

使用前动态申请相机权限。
Android7.0以上需要 声明FileProvider （https://www.jianshu.com/p/47fcd7873f39）

开始

    val CAPTURE_REQUEST = 123
    var mFilePathCallback: ValueCallback<Array<Uri>>? = null //webview内部回调
    var captureUri: Uri? = null //使用该uri接收系统返回的图片/视频

    fun file2Uri(file: File): Uri {
                    //Android 7.0以上需要使用fileprovider
                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                        val authority = application.packageName + ".provider"
                        return FileProvider.getUriForFile(Utils.getApp(), authority, file)
                    } else {
                        return Uri.fromFile(file)
                    }
     }

     mWebview.webChromeClient = object : WebChromeClient() {
             /**
             * 复写该方法
             */
            override fun onShowFileChooser(webView: WebView?, filePathCallback: ValueCallback<Array<Uri>>?, fileChooserParams: FileChooserParams?): Boolean {

          

                mFilePathCallback = filePathCallback

                if (fileChooserParams?.acceptTypes?.isNotEmpty() == true) {
                    val mipmap = fileChooserParams.acceptTypes[0]

                    when (mipmap) {
                        "image/*" -> {
                            val file = File(getExternalFilesDir(Environment.DIRECTORY_PICTURES), "imageCapture${System.currentTimeMillis()}.jpg")
                            ///文件路径 storage/emulated/0/Android/data/包名/files/Pictures/imageCapture1563956535105.jpg
                            captureUri = file2Uri(file)
                            val intent = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
                            intent.putExtra(MediaStore.EXTRA_OUTPUT, captureUri)
                            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
                            startActivityForResult(intent, CAPTURE_REQUEST)

                            return true
                        }

                        "video/*" -> {
                            val file = File(getExternalFilesDir(Environment.DIRECTORY_PICTURES), "videoCapture${System.currentTimeMillis()}.mp4")
                            ///文件路径 storage/emulated/0/Android/data/包名/files/Pictures/videoCapture1563956535105.mp4
                            captureUri = file2Uri(file)
                            val intent = Intent(MediaStore.ACTION_VIDEO_CAPTURE)
                            intent.putExtra(MediaStore.EXTRA_OUTPUT, captureUri)
                            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
                            startActivityForResult(intent, CAPTURE_REQUEST)
                            return true

                        }
                    }
                }
                return super.onShowFileChooser(webView, filePathCallback, fileChooserParams)
            }


        }

接收返回结果

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (requestCode == CAPTURE_REQUEST) {
            if (resultCode == Activity.RESULT_OK) {
                mFilePathCallback?.onReceiveValue(arrayOf(captureUri)) //给回调设置数据
            } else
                mFilePathCallback?.onReceiveValue(arrayOf()) //给回调设置空数据
        }
    }