Question

当用户单击WebView中的链接时，我需要下载文件。当我在chrome应用程序中执行相同操作时，该操作正常工作，但在Webview中不起作用。我已经提到了多个问题，并尝试实施提供的解决方案，但这没有用。

提到了Stackoverflow问题并尝试了解决方案。

Android Webview not triggering a href download file

How to download files from webview Android?

我使用的WebView代码，

    wv_main.getSettings().setJavaScriptEnabled(true);
    wv_main.getSettings().setDomStorageEnabled(true);
    wv_main.getSettings().setAllowFileAccess(true);
    wv_main.getSettings().setAllowFileAccessFromFileURLs(true);
    wv_main.getSettings().setAllowUniversalAccessFromFileURLs(true);
    wv_main.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
    wv_main.getSettings().setBlockNetworkLoads(false);
    wv_main.getSettings().setAllowContentAccess(true);
    wv_main.getSettings().setPluginState(WebSettings.PluginState.ON);
    wv_main.setDownloadListener(new DownloadListener() {
        @Override
        public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimetype, long contentLength) {
            DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url));

            request.setDescription("Download file...");
            request.setTitle(URLUtil.guessFileName(url, contentDisposition, mimetype));
            request.allowScanningByMediaScanner();
            request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED); //Notify client once download is completed!
            request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, URLUtil.guessFileName(url, contentDisposition, mimetype));
            DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
            dm.enqueue(request);
            Toast.makeText(getApplicationContext(), "Downloading File", Toast.LENGTH_LONG).show();
        }
    });

    wv_main.setWebViewClient(new WebViewClient() {

        private int webViewPreviousState;
        private final int PAGE_STARTED = 0x1;
        private final int PAGE_REDIRECTED = 0x2;

        @Override
        public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
            // Get cert from SslError
            SslCertificate sslCertificate = error.getCertificate();
            Certificate cert = getX509Certificate(sslCertificate);
            if (cert != null && certificate != null) {
                try {
                    // Reference: https://developer.android.com/reference/java/security/cert/Certificate.html#verify(java.security.PublicKey)
                    cert.verify(certificate.getPublicKey()); // Verify here...
                    handler.proceed();
                } catch (CertificateException | NoSuchAlgorithmException | InvalidKeyException | NoSuchProviderException | SignatureException e) {
                    super.onReceivedSslError(view, handler, error);
                    e.printStackTrace();
                }
            } else {
                super.onReceivedSslError(view, handler, error);
            }
        }

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String urlNewString) {
            webViewPreviousState = PAGE_REDIRECTED;
            wv_main.loadUrl(urlNewString);
            return true;
        }

        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);
            webViewPreviousState = PAGE_STARTED;
            Log.e("Start Loading", "Start Loading.........");
            /*if (dialog == null || !dialog.isShowing())
            dialog = ProgressDialog.show(MainActivity.this, "", "Loading", true, true);*/
        }

        @Override
        public void onPageFinished(WebView view, String url) {

            if (webViewPreviousState == PAGE_STARTED) {
                //dialog.dismiss();
                Log.e("Loading Done", "Loading Done.........");
            }
        }

        @Override
        public void onReceivedError(WebView view, WebResourceRequest request,
                                    WebResourceError error) {
            super.onReceivedError(view, request, error);
            Toast.makeText(SecretLinkBrowserActivity.this, "Error:" + error.toString(), Toast.LENGTH_SHORT).show();
        }
    });
    wv_main.setWebChromeClient(new WebChromeClient() {
        @Override
        public void onPermissionRequest(final PermissionRequest request) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                request.grant(request.getResources());
            }
        }

        @Override
        public boolean onJsAlert(WebView view, String url, String message, JsResult result) {

            Log.d("LogTag", message);
            result.confirm();
            return true;
        }
    });

在调试时，我注意到单击链接时shouldOverrideUrlLoading()没有被调用。网站进行下载的方式是，他们使用了doPostBack()来动态生成网址并下载文件。

Answer 1

您可以启动一个新的意图，并允许用户选择另一个应用程序进行下载，如下所示：

wv_main.setDownloadListener(new DownloadListener() {
public void onDownloadStart(String url, String userAgent,
            String contentDisposition, String mimetype,
            long contentLength) {
    Intent i = new Intent(Intent.ACTION_VIEW);
    i.setData(Uri.parse(url));
    startActivity(i);
}
});

但是我想您想使用下载管理器，您缺少setDestinationUri方法调用，应该是这样的

DownloadManager.Request request=new DownloadManager.Request(Uri.parse(url))
           .setTitle("Dummy File")// Title of the Download Notification
           .setDescription("Downloading")// Description of the Download Notification
           .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE)// Visibility of the download Notification
           .setDestinationUri(Uri.fromFile(file))// Uri of the destination file
           .setRequiresCharging(false)// Set if charging is required to begin the download
           .setAllowedOverMetered(true)// Set if download is allowed on Mobile network
           .setAllowedOverRoaming(true);// Set if download is allowed on roaming network

单击Android WebView中的链接无法开始下载文件

1 个答案: