Question

我的Web应用程序是使用JSF2.2和PrimeFaces 5构建的。我有一个用户可以下载文档的功能。（＆＃34; .pdf＆＃34;，＆＃34; .csv＆＃34;，＆＃34; .xls＆＃34;和＆＃34; .log＆＃34;）

我创建了一个android webview应用程序并加载了URL，除了下载功能外，一切正常。当我使用桌面浏览器或Chrome等移动浏览器访问网址时，Firefox下载工作正常，没有任何问题，文件下载成功。

我尝试调试应用程序并找到＆＃34; DownloadListener＆＃34;甚至在下载点击时都没有调用。

primefaces按钮：

<p:commandButton id="download" action="#{documents.download()}" icon="ui-icon ui-icon-arrow-d" styleClass="mpzero" ajax="false" update="@form" />

java下载：

public void download() throws IOException {
        byte[] pdfData = null;
        String fileName = null;
        String docId = "13215466546";
        documents = new Documents();
        pdfData = service.getPdfdoc(docId);
        if (pdfData != null) {
            FileOutputStream f = null;
            try {
                FacesContext facesContext = FacesContext.getCurrentInstance();
                ExternalContext externalContext = facesContext.getExternalContext();
                HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
                response.reset();
                response.setContentLengthLong(pdfData.length);
                response.addHeader("Pragma", "no-cache");
                response.addHeader("Cache-Control", "no-cache");
                response.addHeader("Cache-Control", "no-store");
                response.addHeader("Cache-Control", "must-revalidate");
                response.addHeader("Expires", "-1");
                SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
                fileName = "Doc_" + sdf.format(Calendar.getInstance().getTime()) + docId;
                response.setHeader("Content-disposition", "attachment; filename=\"" + fileName + ".pdf\"");
                OutputStream output = response.getOutputStream();
                output.write(pdfData);
                output.close();
                facesContext.responseComplete(); 
            } catch (Exception e) {
            } finally {
                if (f != null)
                    f.close();
            }
        } else {
            //do something
        }

Android Webview：

public class MainActivity extends AppCompatActivity {

         @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(activity_main);
            WebView mywebview = (WebView) findViewById(webview);
            mywebview.clearCache(true);
            mywebview.clearHistory();
            CookieManager cookieManager = CookieManager.getInstance();
            cookieManager.removeAllCookies(null);
            cookieManager.flush();

            WebSettings myView = mywebview.getSettings();
            myView.setAllowFileAccess(false);
            myView.setGeolocationEnabled(false);
            myView.setAppCacheEnabled(false);
            myView.setCacheMode(WebSettings.LOAD_NO_CACHE);
            myView.setJavaScriptEnabled(true);
            myView.setBuiltInZoomControls(false);

            mywebview.loadUrl(url);
            mywebview.setWebViewClient(new MyWebViewClient());
        }

        private class MyWebViewClient extends WebViewClient implements 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.setMimeType(mimeType);
                String cookies = CookieManager.getInstance().getCookie(url);
                request.addRequestHeader("cookie", cookies);
                request.addRequestHeader("User-Agent", userAgent);
                request.setDescription("Downloading file...");
                request.setTitle(URLUtil.guessFileName(url, contentDisposition,
                        mimeType));
                request.allowScanningByMediaScanner();
                request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_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();
            }
        }
    }

由于此下载问题，我的申请不完整。我在这里做错了什么，请建议我一个解决方案。提前谢谢。

Android的WebView - 在jsf中使用<p：commandbutton>下载文件无效

0 个答案: