download method

Implementation

void download({
  required String urlPath,
  required String filename,
  Map<String, dynamic>? params,
  Map<String, dynamic>? body,
  Options? options,
  CancelToken? cancelToken,
  ProgressCallback? onProgress,
  OnSuccess<File?>? onSuccess,
  OnFailed? onFailed,
}) async {
  if (isWeb()) {
    var uaType = await DeviceUtil.getUaType();
    if (!uaType.isWeb) {
      var success = await urlPath.launch();
      if (success) {
        onSuccess?.call(null);
      } else {
        onFailed?.call(CstException.buildException("Url launch 失败"));
      }
    } else {
      // 如果是Web端，通过js交互实现。注意，需要将index.html下的<script>代码复制到自己项目指定位置
      // Web端需要单独处理是因为dio的下载不支持Web端
      webOnProgress(progress, total) {
        if (onProgress != null) {
          onProgress(progress, total);
        }
      }

      webOnSuccess() {
        if (onSuccess != null) {
          onSuccess(null);
        }
      }

      webOnFailed(e) {
        if (onFailed != null) {
          onFailed(CstException(-1, e.toString()));
        }
      }

      js.context.callMethod('download',
          [urlPath, filename, webOnProgress, webOnSuccess, webOnFailed]);
    }
  } else {
    var targetFile = await getDownloadPath(filename: filename);
    try {
      // 其他端使用dio的下载
      await _dio.download(urlPath, targetFile.path,
          queryParameters: params,
          data: body,
          options: options,
          deleteOnError: true,
          lengthHeader: Headers.contentLengthHeader,
          cancelToken: cancelToken, onReceiveProgress: (progress, total) {
        if (onProgress != null) {
          onProgress(progress, total);
        }

        if (cancelToken?.isCancelled == true && onFailed != null) {
          onFailed(CstException(-1, "下载已取消"));
        }

        if (cancelToken?.isCancelled == false &&
            total != -1 &&
            progress >= total &&
            onSuccess != null) {
          onSuccess(targetFile);
        }
      });
    } catch (e) {
      if (onFailed != null) {
        String? detailMessage;
        if (e is Error) {
          detailMessage = e.stackTrace?.toString();
        } else {
          detailMessage = e.toString();
        }
        onFailed(CstException(-1, "下载失败", detailMessage: detailMessage));
      }
    }
  }
}