在android WebView中点击链接未开始下载文件

webView.setWebViewClient(new WebViewClient() {
    @Override
    public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
        // 处理文件下载请求
        if (request.getRequestHeaders().containsKey("Content-Disposition")) {
            String contentDisposition = request.getRequestHeaders().get("Content-Disposition");
            String fileName = extractFileName(contentDisposition);
            String url = request.getUrl().toString();
            startDownload(url, fileName); // 调用下载方法开始下载文件
            return true;
        }
        return super.shouldOverrideUrlLoading(view, request);
    }

    // 提取文件名的方法示例（根据具体服务器返回的Content-Disposition头进行解析）
    private String extractFileName(String contentDisposition) {
        String fileName = null;
        if (contentDisposition != null) {
            int index = contentDisposition.indexOf("filename=");
            if (index > 0) {
                fileName = contentDisposition.substring(index + 9);
                if (fileName.startsWith("\"")) {
                    int endIndex = fileName.indexOf("\"", 1);
                    if (endIndex > 0) {
                        fileName = fileName.substring(1, endIndex);
                    }
                }
            }
        }
        return fileName;
    }

    // 文件下载方法示例（根据具体需求选择适合的下载方式）
    private void startDownload(String url, String fileName) {
        // 使用系统的下载管理器进行下载
        DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));
        request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, fileName);
        DownloadManager downloadManager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
        if (downloadManager != null) {
            downloadManager.enqueue(request);
        }
    }
});